ASDSO Journal of Dam Safety 15.4

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VOLUME 15 | ISSUE 4 | 2018

I SSN 1944-9836

IN THIS ISSUE: • The Impact of the Kelly Barnes Dam Failure on the Development of Dam Safety Legislation and Policy in the 1970's • Reducing Relief Well Clogging and Pore-Water Pressures Using Natural Groundwater Pressures and a Packer-Purge System™ • Grout Mix Development for Bedrock Grouting at Dale Hollow Dam • Is the Elephant Even In the Room? – Communicating Flood Risks Related to Dams

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On The Cover During the 2013 floods in Colorado, many spillways were activated that typically are dry. The peak discharge through the Button Rock Dam spillway during the 2013 flood was estimated to be 10,000 cfs. This amount of flow is unusual, exceeds the estimated 100-year flood discharge of 7,400 cfs, and caused significant damage to roads, bridges, and structures along the river flood plain, as shown here.

ISSN 1944-9836 - Association of State Dam Safety Officials

ASDSO Disclaimer for Journal of Dam Safety The material presented in this ASDSO publication has been prepared in accordance with generally recognized engineering principles and practices, and is for general information only. This information should not be used without first securing competent advice with respect to its suitability for any general or specific application. The contents of this publication are not intended to be and should not be construed to be a standard of the Association of State Dam Safety Officials (ASDSO) and are not intended for use as a reference in purchase specifications, contracts, regulations, statutes, or any other legal document. No reference made in this publication to any specific method, product, process or service constitutes or implies an endorsement, recommendation, or warranty thereof by ASDSO. ASDSO makes no representation or warranty of any kind, whether express or implied, concerning the accuracy, completeness, suitability or utility of any information, apparatus, product, or process discussed in this publication, and assumes no liability therefore. Anyone utilizing this information assumes all liability arising from such use, including but not limited to infringement of any patent or patents.



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I S S N 1944-9836 - Association of State Dam Safety Officials

ASDSO Dam Safety Journal

7 Training Calendar

9 The Impact of the Kelly Barnes Dam Failure on the Development of Dam Safety Legislation and Policy in the 1970's

19 Reducing Relief Well Clogging and PoreWater Pressures

29 Grout Mix Development for Bedrock Grouting at Dale Hollow Dam

35 Is the Elephant Even In the Room? – Communicating Flood Risks Related to Dams

44 News Round-Up

56 Advertiser Index

Letter from the Editorial Committee The 1970’s were formative years for dam safety. The near failure of the Lower San Fernando dam due to liquefaction, and the failure of Teton Dam on first filling were two major events that caught the public’s attention. Also, several other events, including one in the President’s home state, helped to kick off national action on dam safety. This issue includes an article on the impact of Dr. Bruce Tschantz and the Kelly Barnes Dam failure on the development of federal dam safety initiatives. This issue also includes an article on well screen blockage and how you can “jutter” to keep your relief wells running at a higher efficiency. There is also an article on development of grout mixes for remediating dams. Finally, there is the elephant in the room. That being flood risk related to dams, which completed this issue. We hope you enjoy the offerings. Jutter on! Each quarter, the Journal features articles by experts in the dam safety community on various topics, timely news events, products, and professional services. The Editorial Committee hopes you’ll enjoy this issue, learn something of value, and perhaps follow up on a reference or make a personal connection. Also, please feel free to contribute an abstract for your interesting project. We are always looking for good papers of interest to the dam safety community. The ASDSO Journal of Dam Safety is a quarterly publication dedicated to increasing the technical expertise of engineers, owners, operators, and others involved in dam safety. A primary goal is to promote consistency in technical and regulatory approaches to dam safety with examples from various geographic regions, various types of dams, and from a variety of perspectives. Some issues will reflect a specific theme and some issues will share an editorial perspective from an owner, consultant, researcher, or other professional. Articles are selected to share important information, lessons learned, and promote new technologies that can benefit the dam safety community. The Journal is also a valuable source for industry news, organizational updates, and upcoming events. If you have an interesting project or topic to share with your dam safety peers, please contact either co-chair for a copy of Author Guidelines to begin the process with a 1-page abstract. Articles must be original work and appropriate for the readership. Please feel free to email or for more information on authorship or to provide feedback on recent articles. The Committee sincerely hopes you find this publication to be valuable and continually improving.

ISSN 1944-9836 - Association of State Dam Safety Officials

The Journal of Dam Safety welcomes articles from any writer, but the opinions expressed in those articles do not necessarily reflect the opinions and policies of ASDSO.

ASDSO REVIEW TEAM & CONTRIBUTORS: Lori C. Spragens, Executive Director: Susan A. Sorrell, Training Program Director: Sarah McCubbin-Cain, Information Specialist: Ross Brown, Marketing & Membership Director: Katelyn Riley, Communications Manager: Brittany Lewis, Administrative Assistant:

EDITORIAL COMMITTEE: Lori C. Spragens, Executive Director (ASDSO) R. Craig Findlay, Co-Chair (Findlay Engineering, Inc) Mark Schultz, Co-Chair (CA Department of Water Resources) Brian S. Cook (NC Department of Environmental & Natural Resources) Jessie Drayton (AECOM) Keith A. Ferguson (HDR Engineering, Inc.) John W. France (AECOM) James W. Gallagher (NH Department of Environmental Services) Chris R. Karam (Brookfield Renewable) Meghann Wygonik Kinkley (US Army Corps of Engineers) Ian Maki (CA Department of Water Resources) Arthur C. Miller (AECOM) Dusty Myers (MS Department of Environmental Quality) Alan Rauch (Stantec Consulting Services) Nathan J. Snorteland (US Army Corps of Engineers) William Sturtevant (WI Department of Natural Resources) James H. Weldon (Jim Weldon and Associates, LLC) Web site: The Journal of Dam Safety is compiled, written and edited by the Association of State Dam Safety Officials, 239 S. Limestone St., Lexington, KY 40508, (859) 550-2788, Toll Free: (855) 228-9732, Fax: (859) 550-2795, Email:



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I S S N 1944-9836 - Association of State Dam Safety Officials

ASDSO 2017-2018 Board of Directors

Metric Conversion It is intended that articles in the ASDSO Journal of Dam Safety be in English measurements. In order to assist our international partners in dam safety, we also want to include the international SI system of measurements.

Jonathan D. Garton, P.E. (President) Iowa



25.40 Millimeter (mm)

1 Millimeter (mm)


1 Feet (ft)


30.48 Centimeter (cm)

1 Centimeter (cm)


0.04 Inch (in) 0.03 Feet (ft)

1 Feet (ft)

= 0.3048 Meter (m)

1 Meter (m)


3.281 Feet (ft)

1 Yard (yd)


0.914 Meter (m)

1 Meter (m)


1.094 Yard (yd)

1 Mile (mi)


1.609 Kilometer (km)

1 Kilometer (km)


0.621 Mile (mi)

Roger Adams, P.E. (President-Elect) Pennsylvania Hal Van Aller, P.E. (Treasurer) Maryland

MASS CONVERSIONS 1 Pound-Mass (lbm)


1 Gram (g)


0.0022 Pound-Mass (lbm)

1 Pound-Mass (lbm)

= 0.4536 Kilogram (kg)

453.6 Gram (g)

1 Kilogram (kg)


2.2046 Pound-Mass (lbm)

1 Ounce (oz)


28.35 Gram (g)

1 Gram (g)


0.04 Ounce (oz)

1 Slug


14.59 Kilogram (kg)

1 Kilogram (kg)


0.07 Slug

Bill McCormick, P.E., P.G. (Secretary) Colorado Dusty Myers, P.E. (Immediate Past President) Mississippi

FORCE CONVERSIONS 1 Pound-Force (lbf )


4.448 Newton (N)

1 Newton (N)

1 Kip


1000 Pound-Force (lbf )

1 Pound-Force (lbf )

= 224.8089 Pound-Force (lbf ) =

0.001 Kip

1 Ton


2000 Pound-Force (lbf )

1 Pound-Force (lbf )


1x10-4 Ton

1 Ton


4.448 Kilonewton (kN)

1 Kilonewton (kN)


0.1020 Ton

1 Kip

= 4448.2 Newton (N)

1 Newton (N)

= 2.23x10-4 Kip

1 Ibf/Inch2 (psi) 1 Atmosphere (atm)

= 14.96 Pascal (Pa) = 1.013x105 Newton/meter2

1 Inch2 (in2)


1 Foot2 (ft2)

Alon Dominitz, P.E. New York Nathan Graves P.E. Wyoming


= 1.45x10-4 Ibf/Inch2 (psi) = 9.87x10-6 Atmosphere (atm)

Ann Kuzyk, P.E. Connecticut

AREA CONVERSIONS 1 Centimeter2 (cm2)


0.1550 Inch2 (in2)

= 0.0929 Meter2 (m2)

1 Meter2 (m2)


10.76 Foot2 (ft2)

1 Yard (yd )


0.836 Meter (m )

1 Meter (m )


1.196 Yard2 (yd2)

1 Mile2 (mi2)


2.590 Kilometer2 (km2)

1 Kilometer2 (km2)


0.386 Mile2 (mi2)

1 Mile2 (mi2)


640.0 Acre

1 Acre


0.0016 Mile2 (mi2)



6.451 Centimeter2 (cm2) 2




Yohanes Sugeng, P.E. Oklahoma Kenneth E. Smith, P.E. Indiana



1 Centimeter3 (cm3)


0.0610 Inch3 (in3)

1 Foot3 (ft3)

= 0.0283 Meter3 (m3)

1 Meter3 (m3)


35.31 Foot3 (ft3)

1 Yard (yd )


0.764 Meter (m )

1 Meter (m )


1.308 Yard3 (yd3)

1 Pint


0.473 Liter (L)

1 Liter (L)


2.113 Pint

1 Gallon


3.785 Liter (L)

1 Liter (L)


0.2642 Gallon

1 Acre-Foot (acre-ft)


1233 Meter3 (m3)

1 x106 Meter3 (m3)


1 Feet/Second (fps)

= 0.3048 Meter/Sec (m/s)

1 Meter/Sec (m/s)


3.281 Feet/Second (fps)

1 Miles/Hour (mph)


1 Kilometer/Hr (km/s) =

0.621 Miles/Hour (mph)



16.39 Centimeter3 (cm3) 3




Ed Knight, P.E. Louisiana Charles N. Thompson, P.E. New Mexico

811 Acre-Foot (acre-ft)

VELOCITY CONVERSIONS 1.609 Kilometer/Hr (km/s)

David Griffin, P.E. Georgia

FLOW CONVERSIONS 1 Gallons/Minute (gpm)

= 0.0022 Foot3/Second (cfs)

1 Foot3/Second (cfs)


1 Acre-feet/Second

= 1233.48 Meter3/Sec (cms)

1 Meter3/Sec (cms)


35.32 Foot3/Second (cfs)

1 Foot /Second (cfs)


6.463 x106 Gallons/Day (mgd)

1 x10 Gallons/Day (mgd) = 6

1.547 Foot /Second (cfs) 3


Paul G. Schweiger, P.E. Gannett Fleming, Inc. Advisory Committee Chair

450 Gallons/Minute (gpm)


= ([°Fahrenheit]-32)/1.8

n Fahrenheit (°F) = [°Celsius]x1.8+32

n Kelvin (°K)

= ([°Fahrenheit]+459.7)*(5/9)


Fahrenheit (°F)



ADVERTISING RATES AND INSERTION The Journal of Dam Safety accepts advertising. Because of its status as a charitable, educational institution and because of postal laws regarding postage rates for nonprofit organizations, ASDSO cannot accept advertising from insurance, travel and credit card companies. All ad rates are for four color ads. ASDSO Sustaining Members receive 25% off Full and 1/2 page ads. For complete information on advertising rates, download the Journal of Dam Safety media kit at, or contact Ross Brown,, (859) 550-2788. Mechanical Requirements


Full Page. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 H x 7 W 1/2 Page. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 3/4 H x 7 W 1/4 Page Vertical. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 3/4 H x 3 1/2 W Professional Listing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 H x 3 1/2 W ISSN 1944-9836 - Association of State Dam Safety Officials

RATES Member Rate


4X (Yearly)

Full Page 1/2 Page 1/4 Page Vertical Professional Listing

$1,656 $1,296 $1,080 $900

$2,760 $2,160 $1,800 $1,500

Non Member Rate


4X (Yearly)

Full Page 1/2 Page 1/4 Page Vertical Professional Listing

$2,136 $1,776 $1,580 $1,380

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I S S N 1944-9836 - Association of State Dam Safety Officials

2018-2019 ASDSO Training Calendar View additional information including agenda and registration details at



MARCH 2019

JUNE 2019




Dam Safety 2018 Seattle, WA


West Regional Conference

18-20 Classroom Seminar:

Drone Technology Integrated into Dam Safety Inspections and Evaluations

Westminster, CO


APRIL 2019

HEC-HMS Indianapolis, IN


16-18 Classroom Seminar:



Conduits, Gates and Valves

Dam Safety 2019


Glendale, CO

Orlando, FL

Why Embankments Crack and How to Fix Them


MAY 2019 21-23 Classroom Seminar:


Seepage Through Earthen Dams


Austin, TX

How to Conduct a Successful PFMA Lessons Learned from Past Successes and Failures

ASDSO Webinars Available in Downloadable or On-Demand Format All previously held ASDSO Webinars are available in digital archived format for on-demand viewing. Participants receive access to the recorded event (audio and slide presentation), may download the handouts or reference materials, and with the On-Demand option, can take the quiz for professional development credit. The full library contains over 80 titles, including these recently completed training events:

• Findings of the Oroville Dam Spillway Forensic Investigation •

HEC-RAS 2D Modeling

Risk Communication for Dams

Introduction to Addressing Inadequate Conveyance Capacity at Dams

View the full list and register at

ISSN 1944-9836 - Association of State Dam Safety Officials



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Dean B. Durkee, PhD, PE • Paul G. Schweiger, PE, CFM • Offices • 800.233.1055 8 THE JOURNALWorldwide OF DAM SAFETY •| VOLUME 15 | ISSUE 4 | 2018 I S S N 1944-9836 - Association of State Dam Safety Officials

The impact of the Kelly Barnes Dam failure on the development of dam safety legislation and policy in the




In the early 1970s, dam safety practices varied widely from state to state. Some states had no dam safety laws at all and many lacked the funding to implement the laws they had. Most laws in place did not include inspection of existing dams, but instead focused on processes for permitting new dam construction. No national laws had been passed related to dam safety at that time. Several federal laws were passed that funded the construction of specific dams, but no laws or funding were provided for inspection of existing dams. No national inventory of dams existed either, so the scope of dam safety needs was unknown. Large dam failures earlier in the century influenced some changes in state dam safety law; for example, the 1911 failure of Austin Dam led to Pennsylvania passing the nation’s first dam safety law in 1913 . California dam safety legislation was also updated when St. Francis Dam failed in 1928. But no failure had led to a national dam safety law.

On February 26, 1972, a coal slurry impoundment dam failed, killing 125 people. The influence of the disaster extended far beyond the borders of Buffalo Creek, West Virginia, to the halls of Congress, and on May 30 and 31, 1972, hearings were held before the U.S. Senate Committee on Labor and Public Welfare that were presided by Senator Harrison Williams of New Jersey. He opened the hearings stating, “Time and time again in the course of our committee’s work …we have been told that these tragedies are a part of the business with the implication that they are to be naturally expected…Our inquiry is designed to show in detail how this disaster took place.”

What leads to the passage of a dam safety law? Tireless work promoting dam safety and associated public safety impacts, or an actual disaster? The 1970s was perhaps the most significant decade for development of dam safety laws and regulations in the United States. This eventful time is often attributed to the dam failures that occurred in these years, most notably, Buffalo Creek (WV) in 1972, Teton Dam (ID) in 1976, and Kelly Barnes Dam (GA) in 1977. This article highlights the status of dam safety laws and guidelines at that time and how they were affected by these significant disasters, and also examines the roles of the technical and non-technical communities that worked tirelessly prior to and after the disasters to make significant legislative change.

ISSN 1944-9836 - Association of State Dam Safety Officials

The investigation of the disaster led to a desire to create national law for the safety of dams. As part of events moving toward that goal, a hearing was held before the Senate Committee on Interior and Insular Affairs on July 20, 1972. Washington Senator Henry “Scoop” Jackson, who chaired the committee, opened the hearing with references to the Buffalo Creek disaster, as well as the later failures of Canyon Lake and Fort Meade dams in South Dakota. He stated, “These occurrences point up the grim fact that there are innumerable dams in existence throughout the United States which are under no effective public control to ensure that they were competently designed and constructed initially, that they are being adequately inspected and maintained, or that the design remains adequate under current hydrologic conditions in the watershed.” Further, Utah Senator Wallace Bennett presented draft bill S. 449 to have the Water Resources Council (made up of department and agency leaders who coordinated water programs throughout the nation) take the lead in developing a federal dam safety program with



a $5 million annual budget. Technical assistance would be provided by the Bureau of Reclamation, the U.S. Geological Survey, the U.S. Army Corps of Engineers and the Soil Conservation Service to support state programs of licensing and inspection. However, in written testimony, the Assistant Secretary of the Interior wrote, “We recommend that the bill not be enacted…This Department concurs in the view underlying the bill that increased attention should be given to assuring the safety of dams…We feel however, that safety of non-Federal dams is primarily a State responsibility. S. 449 recognizes this but would encourage States to assume that responsibility by offering Federal technical assistance on a non-reimbursable basis. We do not know at this time enough about the dimensions of the non-Federal dam problem to determine the extent of Federal involvement, if any, which may be justified.” The Office of Management and Budget (OMB), U.S. Department of Agriculture, the U.S. Army Corps of Engineers, and the Water Resources Council itself, all recommended the bill not be enacted. Several states also testified, but they were in support of the bill. As the process moved forward, the focus came onto the U.S. Army Corps of Engineers to take the lead. Neil Parrett, who worked with the U.S. Army Corps of Engineers in Washington, DC, in 1972, recalls, “One Friday our congressional liaison came running in and stated that Congress needed to know the number of dams in America

and how much money it would cost to fix those dams. At that point, we hadn’t done any inventory so our boss asked each of the Division Chiefs to go into a room and write our best guess for each number on a piece of paper. He gathered the papers together, took the average, and sent it to Congress. I don’t recall the exact number, but after we did our inventory in 1975, it turned out we were very close.”

PUBLIC LAW 92-367 Legislation worked its way through Congress and on August 8, 1972, Public Law (P.L.) 92-367 was signed into law. Now known as the “National Dam Inspection Act,” it required an inspection of all dams (defined as a barrier 25 feet or more in height with a capacity of 50 acre-feet or more) with just a few exceptions. Despite such a mighty undertaking, no funding was approved at the time for inspections, nor were any deadlines or frequency of inspections established. President Nixon even expressed concerns about this legislation. In a statement released on August 9th, the day after the law became official, he remarked, “The objective of this bill – to reduce the risk of dam failures – is highly desirable, as we have learned from painful experience. I think the particulars of this bill are most unfortunate, however, for they depart from the sound principle that the safety of non-Federal dams should primarily rest with the States. This bill is also marred because it was enacted hastily, without benefit of committee hearings, advice from the concerned agencies of the

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I S S N 1944-9836 - Association of State Dam Safety Officials

executive branch, or comments by the affected States…More than 28,000 dams may be involved, but the bill fails to establish any inspection priorities. And the cost of the program may run as high as $100 million.” The bill also required the Secretary of the Army to prepare a report to Congress by July 1, 1974 that would include an inventory of all dams in the United States, and a review of each inspection. The report was to also include recommendations for a comprehensive national inspection program, and the responsibilities to be assumed by federal, state, and local governments, and by public and private interests.

1975 REPORT – NATIONAL PROGRAM OF INSPECTION OF DAMS The report required by P.L. 92-367 was delivered to Congress several months late in May 1975. It included an inventory of dams based on survey responses from each state. The final inventory number was 49,329 dams, as defined by the Act. However, this number could hardly be considered comprehensive, as 10 states said the total number was unknown, and per Alabama Governor George Wallace, the only dam in Alabama ‘inexplicably collapsed’ on February 10, 1975, just prior to the publication of the report. Despite the likelihood of the 49,000+ number being extremely underestimated, it was the number that was used to estimate workloads and budgets for the next several years. Of the 20,000 dams that were identified that could result in loss of life, 9,000 were estimated to be high hazard dams and 11,000 were estimated to be significant hazard dams. It was recommended that the inspection of all existing dams having a high or significant hazard potential would be inspected under the National Dam Safety Program. States would be responsible for dams under their authority, but federal agencies could assist with the state programs upon request.

TETON DAM AND HEARINGS On June 5, 1976 Teton Dam, a Bureau of Reclamation dam in Idaho, failed during its first fill, killing 11 people. This failure rekindled an interest in dam safety, but with an increased focus on federal dams and their associated safety programs. On August 5, 1976, Congressional hearings chaired by California Congressman Leo Ryan were held on the disaster. He opened the hearings remarking on a site visit he had taken to Teton, “I felt, as I looked at the remains of the dam there in that valley, that it is a gigantic monument to human failure – and to the failure of government. We cannot excuse this disaster by calling it an ‘act of God.’ This was not a natural disaster. We did this ourselves.” The impact of this failure and the subsequent hearings would again turn attention to conceiving – and implementing – federal dam safety guidelines.

JIMMY CARTER, THE LA TIMES, AND MORE HEARINGS In November 1976, a few months after Teton Dam failed, Georgia Governor Jimmy Carter was elected as the 39th President of the United States. Early in his term, President Carter designated dams and their impact as an important issue. He wanted many new dam construction projects ended by cutting them from the budget, resulting in a water project “hit list” (Figure 1). Figure 2 shows a letter from the President to New York Congressman Jerome Ambro seeking support to remove these projects from funding consideration in 1977. However, the budget for that fiscal year included funding for most of these projects.

In order to perform the initial inspections on all high or significant hazard dams, the Army requested $30 million over a five-year period, or $5,000 per dam to complete this work. The report also included guidelines for safety inspections and evaluations of the dams that could be used to perform them. In referring to the actual inspections, the report stated, “No inspections authorized by Public Law 92-367 have been performed due to limited funding and the belief is that such inspections of non-Federal dams should be accomplished by the concerned States as part of their normal responsibilities.” For federal dams, it was made clear that the federal agency owning, operating or managing the dam would be responsible for inspections. If agencies did not have the expertise, the report states they could go to those agencies that did, directly listing the U.S. Army Corps of Engineers and Bureau of Reclamation as examples. After the report was submitted to Congress, the Army requested funds to implement the program and put forth additional proposed legislation; however, no further action was taken at the time.

ISSN 1944-9836 - Association of State Dam Safety Officials

Figure 1: The ‘hit list’ of water projects submitted to Congress by President Carter. Photo by N. Gee taken at the Jimmy Carter Presidential Library and Museum, 2/1/2017.



While the President worked to limit future dam construction, much of the nation was still focused on dam safety, and on March 13-18, 1977, the Los Angeles Times ran a series of articles on dam safety by reporter Gaylord Shaw. The lead to the series read, “For more than 50 years, government agencies and private developers have been busy damming up the nation’s rivers and streams…But now, a month-long Times investigation shows, many of these dams have become time bombs.” These articles clearly did not go unnoticed by the President as a copy was found in his personal secretary’s files in his Presidential Library. And only two days after the initial article ran, Congressional hearings (chaired once again by California Congressman Ryan) on dam safety were again initiated, featuring questions about why the nation was not further along in its dam safety program development since passage of the 1972 law. Ryan opened the hearings, remarking, “In 1972…we called for a nationwide inspection of all dams…It is now five years later and none of those inspections has been performed… We hope that through these hearings we can begin to construct the foundations for a national program of dam safety…If we are unable to learn from our failures and disasters, we must be resigned to suffer them again and again.” Figure 2: Letter from President Carter to New York Congressman Jerome Ambro. Photo by N. Gee taken at the Jimmy Carter Presidential Library and Museum, 2/1/2017.

About a month after the hearings began, a Presidential Memo on dam safety was submitted on April 23, 1977 to all federal agencies that were involved in dam construction and operation. It called for a review of the current dam safety programs in each agency. An interagency report and proposed federal guidelines for dam safety were due to the President on October 1, 1977; these were followed by an independent panel review, and finalized by October 1, 1978. Dr. Bruce Tschantz, a professor at the University of Tennessee, was instrumental in developing guidelines for this task and in getting Tennessee to enact the “Safe Dams Act of 1973.” He was also interviewed in Gaylord Shaw’s articles and provided key testimony in the 1977 Congressional hearings. Now, the Carter administration looked to him to help keep the federal agencies on target to meet the President’s October deadline. He began working with Dr. Phil Smith under Frank Press, Director of the White House’s Office of Science and Technology Policy (OSTP) in early 1977.

Figure 3: Handwritten note and excerpts from two pages of a draft memo dated July 26, 1977. OMB struck out specific wording that stated agreement on funding the inspection program. Photo by N. Gee taken at Jimmy Carter Presidential Library, 2/1/2017.



In an official memo to the OMB on July 13, 1977, Dr. Tschantz’s office recommended funds be set aside to begin the inspection program for non-federal dams that was authorized in the 1972 law. One week later, on June 20, 1977, seven non-federal dams in Pennsylvania failed, causing what is known as the Johnstown Flood. 85 people were killed. Despite the deaths in Johnstown (caused by the failure of Laurel Run Dam and subsequently, six other dams downstream), OMB called the event an “act of God” and still questioned funding the inspection program. Figure 3 shows edits OMB made to a draft memo from OSTP Director Frank Press to the President dated July 26, 1977; however, a note on the top of the memo states, “Not sent because OMB accepted our recommendations to fund Federal inspections.”

I S S N 1944-9836 - Association of State Dam Safety Officials

The result was a new proposal to include $15 million in fiscal year 1978 funding to perform inspections. Now that OMB agreed to this approach, the bill for funding could move the House and the Senate reviews toward approval.

KELLY BARNES DAM AND THE AFTERMATH In the early hours of November 6, 1977 in Toccoa Falls, Georgia, Kelly Barnes Dam failed, flooding the Toccoa Falls Bible College and killing 39 people. Georgia Governor George Busbee contacted the U.S. Army Corps of Engineers to request assistance under its emergency action authority. The next day (Monday, November 7th), lead elements consisting of geotechnical and hydraulic engineers immediately began evaluating the site. Technicians and surveyors followed, as did a drill rig and crew for sampling.

involvement efforts were undertaken to obtain data about the history, construction, and operation of the dam. News releases were issued on November 10 and 14 soliciting information and input. Public notices were mailed to every household and business in the area asking for first-hand knowledge of the incidents leading to the failure, copies of old photographs (Figure 4), details of earlier construction features, and observations based on visits to the dam.

The evaluation team was tasked with gathering a history of the dam and pre-failure weather conditions at the site; documenting the post-failure site and surrounding area through visual inspection, topographic surveys, and photo documentation; performing hydraulic modeling using National Weather Service data; and evaluating various failure scenarios to help develop a reasonable failure hypothesis. A Federal Investigative Board was also established consisting of representatives from the U.S. Army Corps of Engineers, U.S. Geological Survey, National Weather Service, and Soil Conservation Service. Immediately after the formation of the board, public

Figure 4: Photo of earthmover, perhaps belonging to the LeTourneau Company, working on Kelly Barnes Dam circa 1948. The LeTourneau Company, at the time one of the nation’s largest manufacturers of heavy earthmoving equipment, provided equipment for the construction and used the work to test its products. Photo courtesy of Joe Rogers.

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Public hearings on November 17-18 were sparsely attended, but information from them, augmented by research results from the onsite team, helped the dam's history come into focus. Between 1899 and the mid-1940s, the dam was privately owned, beginning as a rock crib dam that furnished water to a small powerplant, later developing into a larger earthen dam. In 1944, the college took over ownership of the powerplant. In 1948-1949, the earth dam was raised to create a 50-acre lake, and two masonry inlet structures were added with 30-inch-diameter welded steel outlet pipes and penstocks. Records indicate there were problems with the pipes collapsing during fill compaction, so reinforcing rods were installed inside some pipes to prevent collapse.

Between 1949 and 1957, the dam continued to serve as a hydropower source, but around 1957, the dam ceased to provide water to the powerplant and the normal pool outlet and penstock outlets were plugged. From this point forward, the only reservoir control was the auxiliary spillway through the left abutment. Reports indicate the spillway routinely flowed and discharged back into Toccoa Creek over a rocky ledge. There is no record of any routine inspection or maintenance on the dam by either the college or any state agency once power production ceased. The lake served as a recreation area up until failure. All reports indicate the dam was so overgrown with trees and brush that it was indistinguishable from the wooded shoreline of the lake. In February 1973, an inspector, possibly from the Soil Conservation Service, visited the site and noted heavy vegetation on the dam, as well as a slide on the downstream face in the vicinity of the outlet pipe. He noted that at that location, a portion of fill had been removed, or there was likely some type of failure near the end of the pipe. The slide was apparently not new as file photos indicate considerable growth over the area.

Figure 5: Photo of two masonry inlet structures installed on Kelly Barnes Dam during 1948-1949 dam modifications. The dam failed in this area in 1977. Photo courtesy of Joe Rogers.



During the course of the U.S. Army Corps of Engineers’ field investigation and site documentation in 1977, the most obvious feature was the gap in the dam that was approximately 120 feet wide at the top and about 60 feet wide at the creek bed. In most of the area, the foundation materials were scoured down to the underlying rock. The dam appeared to have failed on the right side in the area

I S S N 1944-9836 - Association of State Dam Safety Officials

where historical photos would later reveal the presence of two outlet structures and an old slide. The right failure surface was essentially vertical for much of the dam width (Figure 6). The overall slope was measured to be approximately 1 v on 0.5 h. Two welded steel pipes, approximately 30 inches in diameter, were exposed on the failure face. Also, near the dam toe, old timbers and large rocks were observed, which were the remnants of the original crib dam. Tree roots penetrated deep into the dam and were particularly prominent on the downstream slope. Upstream of the dam, several slide areas were noted along the reservoir rim, which were the result of rapid drawdown of the pool during failure.

The layers of exposed alluvium ranged from 2 to 5 feet in total thickness and extended back from the old crib dam area upstream for an indeterminate distance. The lower portion of the alluvium contained extensive root mat. The spillway section and remaining slopes of the dam were overgrown with brush and small trees. On the left end of the dam near the spillway, a campfire site was found. This, along with no signs of disturbed brush on the dam crest, confirmed that the dam did not overtop in a conventional sense. Some have hypothesized that there could have been a low point, or sag, in the dam crest. However, the team found no eyewitness accounts or reports to support this. The debris field, which extended several hundred yards downstream of the dam, was photographed and cataloged. Thirty-inch diameter pipe was scattered along the creek bed, including some pieces of collapsed pipe. Also, pieces of concrete masonry block structures, some as large as 4’ x 4’, were found from the apparent collapse of the intake towers. The metal slide gate supplying the powerhouse penstocks was located. The debris validated many of the reported features of the dam.

Figure 6: Right side of breach of Kelly Barnes Dam. Note pipes, rubble from crib dam, tree root penetration, and flat bedrock foundation. Photo courtesy of Joe Rogers.

Figure 7: Left side of breach - Note root penetration, vegetation and trees on remaining dam, flat rock foundation. Photo courtesy of Joe Rogers.

The left side of the breach (Figure 7) was practically as steep as the right. Transverse tension cracks were noted at the top of the slope, the widest nearer the edge of the failure. The cracks extended about 30 feet back from the failure scarp. These indicated the failure started at the right side of the dam and progressed toward the left. Examination of the cross section revealed about four feet of different colored soil beneath the crest, indicating that the dam was raised in stages over time. Two layers of soft alluvium were observed beneath the embankment in both faces of the breach. ISSN 1944-9836 - Association of State Dam Safety Officials

On November 8, a survey party arrived to make a plane table survey of the dam, breach, and area immediately downstream. Soon thereafter, a drill crew arrived to obtain soil samples from the dam and foundation in an effort to ascertain the material properties and strength for stability analysis. This analysis would be used to better understand why or how the dam failed. Site accessibility limited the sampling locations, but soil samples from the embankment and foundation were tested to determine various properties. Laboratory tests indicated the materials used in the construction to be local residual soils (as expected) generally classified as silts and clays of varying plasticity. Some embankment materials had very low plasticity with indices below 10. The soil compaction varied between 78-86 percent of Standard Proctor density (ASTM D-698), which was considered low, but not inconsistent with the reported construction methods. Pinhole tests indicated the materials were not dispersive, but the region is known for materials of high erodibility. Using software commonly available in the late 1970s, computer analyses were run to simulate possible hydraulic conditions prior to and during failure to estimate the relative stability of the dam. Using National Weather Service data, field surveys, topographic mapping, interviews with local residents, and information regarding the lake capacity, inflow and outflow into the lake was determined for November 5 and 6, 1977. Hydrographic data agreed with eyewitness reports and field observations. The computed maximum water elevation was within half a foot of field measurements, within the margin of error of the computations. Of interest was the fact that the hydrographs indicated that water should have been going over the secondary spillway (low area in right rim of lake) after about 9:00 pm on November 5. The area was visited by local firemen about 10:30 pm and they found no water spilling over the dam or reservoir rim, though field investigations did find that water went over the rim at some point during the event as evidenced by bent vegetation. This THE JOURNAL OF DAM SAFETY | VOLUME 15 | ISSUE 4 | 2018


absence of flow about 10:30 pm might suggest a partial failure prior to the main failure. About 4 feet of freeboard apparently remained on the dam at failure but inspection of grass below about four feet indicated high velocities such as might occur during rapid flow into a breach. The major failure occurred at about 1:30 am on November 6. Field surveys and high water profiles were used to compute possible peak discharges about 1,000 feet below the dam. Peak discharge was computed to be 24,000 cubic feet per second. While the investigation went on, the President had a meeting in the cabinet room on November 7, 1977, with OSTP Director Press. He heard of the failure while at church, and due to his personal connection with the state of Georgia, he and his wife decided she should be onsite as the bodies were pulled from the debris. The briefing material for the meeting contained four options that were outlined in an official memo dated the next day, November 8, 1977. On December 2, 1977, the President announced: “I have directed the secretary of the Army to commence at once the inspection of more than 9,000 non-federal dams that present a high potential for loss of life and property if they fail…We will make $15 million available for the program during this fiscal year, and hope to be able to inspect 1,800 non-federal dams during that year…Because the inspection program will not resolve specific dam safety problems and will not relieve the states or owners of these structures of their responsibilities for public safety, we will ask for Governors to agree, prior to these inspections, to take certain steps toward establishing an adequate state program for dam safety.” These became known as Phase I inspections and thousands were performed over the next few years. Many professionals in the field of dam safety began their careers training for and performing these inspections. The U.S. Army Corps of Engineers team wrapped up fieldwork by mid-November, and the “Report of Failure of Kelly Barnes Dam” was issued by the Federal Investigative Board on December 21, 1977. Despite all the evaluations by the board and others, no single failure mode could be determined. However, a number of plausible scenarios were presented in the report. The board concluded that the dam did not fail from overtopping in the conventional sense. Most likely the failure was due to a slide on the downstream face or piping, or a combination of the two, which ultimately led to a breach of the crest and rapid release of the reservoir.


Neil Parrett, the young employee in Washington D.C. who was working for the U.S. Army Corps of Engineers helped draft the Reclamation Safety of Dams Act, which passed November 2, 1978. He became the first Chief of Dam Safety in the Bureau of Reclamation. Dr. Bruce Tschantz completed the review and finalized the first Federal Guidelines for Dam Safety. Afterward, he was appointed as the first Chief of the Office of Dam Safety after President Carter created the office in 1980 as part of the Federal Emergency Management Agency.

CONCLUSION As Sam Miles, a U.S. Army Corps of Engineers official who helped draft the proposed guidelines, remarked in one of the Los Angeles Times articles, “The level of concern for dam safety always seems to be in direct proportion to the length of time since the last dam disaster.” History shows he is correct. Unfortunately, if one waits for a disaster to occur before putting a plan together, too much time has passed and no action will take place. Real progress is made when tireless work and accomplishments move forward without the catalyst of a disaster or failure. Clearly, the failure of Georgia’s Kelly Barnes Dam and other incidents raised the level of concern in the nation. But if Dr. Tschantz and his colleagues had not done such extensive work prior to the failure of Laurel Run and Kelly Barnes, would the funding for Type I inspections have fallen into place? It is clear that real progress is made by consistent efforts even when the concern is not on the horizon.

REFERENCES Willis, H. B. (Ed.). (1976). Evaluation of Dam Safety Engineering Foundation Conference (p. 6). Pacific Grove, CA: American Society of Civil Engineers. Rose, A. T. (n.d.). The Influence of Dam Failures on Dam Safety Laws in Pennsylvania [PDF]. uploads/2015/07/104_The-Influence-of-Dam-Failures-on-DamSafety-Laws-in-Pennsylvania.pdf St. Francis Dam. (n.d.). Retrieved from wiki/St._Francis_Dam U.S. Congress, Interior and Insular Affairs. (1972). Safety of Dams: Hearing before the Committee on Interior and Insular Affairs [Cong. S. 3449 from 92nd Cong., 2nd sess.].

Congressman Ryan would remain an advocate for dam safety until his tragic death one year after the Kelly Barnes failure when he was assassinated in Jonestown, Guyana.

Buffalo Creek flood. (n.d.). Retrieved from wiki/Buffalo_Creek_flood

Gaylord Shaw, the Los Angeles Times journalist, received a Pulitzer Prize in 1978 for his articles on dam safety.

U.S. Congress, Senate Committee on Labor and Public Welfare. (1972). Hearing before the Subcommittee on Labor. Buffalo Creek (W.Va.) disaster. [92nd Congress, 2nd sess.].



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Water Resources Council. (1978). Retrieved from php?id=cqal78-1236875 Interview with Neil Parrett [Personal interview]. (2016, November 29). Public Law 92-367 (1972). Nixon, Richard. “Statement About Signing a Bill Providing for a National Safety Inspection Program for Dams – August 9, 1972.” The American Presidency Project, by Gerhard Peters and John T. Woolley. (n.d.). http://www. U.S. Army Corps of Engineers, Office of the Chief of Engineers. (1975). National Program of Inspection of Dams. Report of the Chief of Engineers on the National Program on Inspection of Dams, Appendices A-D. Washington DC. a140087.pdf U.S. Congress, House of Representatives Committee on Government Operations. (1977). Hearings Before the Environment, Energy and Natural Resources Subcommittee. [95th Congress, 1st sess.]. U.S. Congress, House of Representatives Committee on Government Operations. (1976). Hearings Before the Conservation, Energy and Natural Resources Subcommittee. [94th Congress, 2nd sess.].

Nathaniel Gee

Supervisory Civil Engineer Bureau of Reclamation 500 Date St. Boulder City, NV, 89005 Nathaniel Gee is a professional civil engineer with the Bureau of Reclamation’s Lower Colorado Region in Boulder City, Nevada. In this role, he serves as project manager for the Dam Safety and Examination of Existing Structures programs that help protect and maintain elements of Reclamation’s aging infrastructure. He performs rope access and dive inspections of some of Reclamation’s largest and oldest dams including Roosevelt and Horse Mesa dams on the Salt River in Arizona, Parker Dam spanning the Colorado River near Lake Havasu City, and the majestic Hoover Dam. Nathaniel received a bachelor’s degree in civil engineering from Brigham Young University, and a master's degree, also in civil engineering, from the University of Nevada - Las Vegas. He lives in Boulder City with his wonderful wife, Jeanine, and six energetic children.

Joseph H. Rogers, P.E.

US Army Corps of Engineers (Retired) 2380 Hawkins Rd Chatham, VA 24531-4736

Shaw, G. (1977, March 13). Unsafe Dams: Red Tape and Politics Snarl Repairs. The Los Angeles Times. Carter, Jimmy. “Memorandum to the Heads of Certain Federal Agencies on Dam Safety – April 23, 1977.” The American Presidency Project, by Gerhard Peters and John T. Woolley. (n.d.). ws/?pid=7404 Smith, P. (1977, July 13). Issues and Recommendation: Dam Safety of Non-Federal Dams. [Letter to Eliot Cutler]. Interview with Bruce Tschantz [Personal interview]. (2016, September 13). McIntyre, J. (1977, November 8). Federal Role in Safety of Non-federal Dams. [Memorandum to the President]. Carter, Jimmy. “Dam Safety Statement on the Initiation of a Federal Inspection Program for Nonfederal Dams – December 2, 1977.” The American Presidency Project, by Gerhard Peters and John T. Woolley. (n.d.). http://www. Gaylord Shaw. (n.d.). Retrieved from https://en.wikipedia. org/wiki/Gaylord_Shaw

ISSN 1944-9836 - Association of State Dam Safety Officials

Joseph H. Rogers is a retired licensed professional engineer. When the Kelly Barnes Dam failure occurred, Mr. Rogers worked for the U.S. Army Corps of Engineers as the chief of the Soils Design Section in the Savannah District’s geotechnical and materials branch. He helicoptered to the site on the day of the failure with the Savannah district engineer when the Georgia governor requested assistance from them. He was the first engineer to visit the failure site. Subsequently, his office was assigned the responsibility of preparing the technical investigation and evaluation of the failure for inclusion in the report of the Federal Investigative Board. Mr. Rogers served 32 years with the U.S. Army Corps of Engineers. He retired in 2000 after spending the last ten years of his career as the Savannah District chief of engineering. He has a bachelor's and a master's degree in civil engineering from VA Tech. Mr. Rogers is a member of the Savannah District Gallery of Distinguished Employees and is a distinguished alumnus of the VA Tech Department of Civil and Environmental Engineering. After retirement, he continued to be involved in dam safety issues, worked part time for the Virginia Office of Dam Safety, and served as a consultant. Now fully retired, he and his wife of 52 years, Kitty, live in Chatham, Virginia where they both continue to be involved in civic and public service.



Local Connections, Global Ideas Our clients face tough decisions with limited resources. That’s why we support leading water associations—like ASDSO—to help make great things possible for our industry.



I S S N 1944-9836 - Association of State Dam Safety Officials

Reducing Relief Well Clogging and Pore-Water Pressures Using Natural Groundwater Pressures and a Packer-Purge System™ BRUCE A. FOWLER STEPHEN J. RABASCA COLIN O’CONNOR

ABSTRACT Installing relief wells to mitigate excess pore-water pressures is a common strategy for achieving acceptable foundation stability at dams and powerhouses. Relief wells are prone to clogging due to fine-grained soil particles and colloids being transported to the well screen with the continual (uninterrupted) groundwater flow. Redevelopment and replacement are typical solutions to well screen clogging, but these options often come at a high cost and may or may not stabilize pore-water pressures for the long term. An ongoing pilot program at an upstate New York powerhouse is bringing together existing methodologies to build a new application, offering an innovative and cost-effective approach to extend relief well life and effectiveness. After installing three relief wells to control pore-water

ISSN 1944-9836 - Association of State Dam Safety Officials

pressures beneath an operating powerhouse, well screen clogging occurred and foundation pore-water pressures increased. Well redevelopment employing conventional techniques (e.g., surging, jetting) provided only temporary success before unacceptable porewater pressures returned. A solution was needed to control the pore-water pressures while avoiding further mobilization of fines and potential piping development. The pilot program combined suspended particle counting technology and the installation of a Packer-Purge System in each relief well to create intermittent flow stoppages and surges released under natural pressure gradients to successfully mitigate well screen clogging and maintain pore-water pressures in foundation soils.



THE PROBLEM OF INCREASING PORE-WATER PRESSURES A subsurface investigation conducted at the Schaghticoke Development Powerhouse (the Powerhouse) in the late 1990s2 revealed the presence of an artesian head condition in the confined sand and gravel aquifer formation beneath the Powerhouse. In 1999, three 8-inch-diameter relief wells were installed on the east side of the Powerhouse to reduce artesian pressures to the Design Basis Value determined by the stability analyses8. Figure 1 is an aerial view of the Powerhouse area showing the location of the three relief wells, RW2, RW3 and RW5, and the five vibrating wire piezometers (VWP), NM3, NM4, NM5, P1 and P2, used to monitor the pore-pressures in the confined aquifer.

Concurrent with the increasing pore-water pressures, the weir flow rate data indicated a decline in the combined volume of discharge of the relief wells from around 150 gallons per minute (gpm) in 2000 to

Since the installation of the relief wells, two Figure 2. VWP Pore-Water Pressure Timeline Plot. interrelated and simultaneous phenomena have been observed at the Powerhouse: 1) Pore-water pressures beneath the Powerhouse have gradually increased to levels around 48 gpm by 20146. approaching the Design Basis Value for the structure; while 2) Flow rates of relief well discharge to the weir have slowly declined. One of the most important outcomes of the 2014 program was the discovery that evacuated formation material from the relief well screens that was recovered in the re-development water led to the conclusions that: 1) The repeated redevelopment using over-pumping (surging) was eroding the well gravel pack, resulting in damage to the wells6, and 2) A form of continuous, non-aggressive relief well purging might represent a better strategy to maintain pore-water pressures below the Design Basis Value.

Figure 1. Schaghticoke Development Powerhouse Area.

Monthly pore-water pressure readings vs. time plots (Figure 2) for VWPs P1, P2, and NM3 illustrate the gradual, but consistent, increase in the elevation head since the relief wells were installed in 1999. By mid-2014, the pore-water pressure data indicated that all three VWPs had reached or exceeded the upper Design Basis Value required to maintain an acceptable safety factor8. The two vertical purple ellipses on Figure 2 reflect re-development efforts performed in 2011 and 2014 in an attempt to restore flow to the relief wells and, in turn, reverse the trend of increasing porewater pressures beneath the Powerhouse5,6. These data illustrate that the traditional redevelopment efforts, no matter how effective in the short term, were not providing a practical long-term solution to well clogging.



As a result of the 2014 program findings, Sevee and Maher Engineers, Inc. (SME) recommended an innovative approach: use well packers and naturally occurring pressure gradients to purge the wells. Note, in this approach, naturally occurring pressure is defined as the ambient groundwater pressure absent the presence of the relief well system. Beginning in 2016, SME conducted a pilot program of the Packer Purge System to test its ability to control Powerhouse porewater pressures, consisting of a Phase I Trial followed by the design and installation of an Automated Packer-Purge System (System).

DESIGN OF SCHAGHTICOKE POWERHOUSE RELIEF WELLS The existing relief wells and piezometers at the Powerhouse are screened in a confined sand-and-gravel aquifer below a low permeability glacial till stratum. The aquifer exhibited up to 25 feet of artesian pressure above the Powerhouse floor prior to installing the relief wells. The three 8-inch-diameter relief wells, spaced some 55 feet apart, were similarly constructed, each averaging about 58 feet in depth, with 60-slot Stainless Steel screen lengths from 23 to 25 feet within a 15-inch-diameter borehole2. The wells are connected to a subsurface horizontal header pipe, located approximately 20 feet I S S N 1944-9836 - Association of State Dam Safety Officials

below surface grade upstream of the Powerhouse, and about 5 feet below the Powerhouse floor. The header pipe serves to collect the artesian discharge from the wells and directs that water to a weir (for flow measurement) before discharging to the Hoosic River.

WELL CLOGGING THEORY Wells used for extracting groundwater disrupt natural groundwater flow patterns and velocities in the subsurface stratigraphy, and in doing so create conditions at the well screen that can produce clogging7. Clogging can result in losses in a well’s specific capacity, and, ultimately, production capacity. Well clogging occurs in three basic forms (and often combinations thereof ) based on the nature of the clogging material(s)7, 16:

EXAMINING THE CORRELATION BETWEEN WELL OPERATING SCENARIOS AND PARTICULATE CLOGGING OF WELLS Van Beek and his associates in the Netherlands have been researching the role of particles in well bore and well screen clogging for several decades13,14,15,16,17 and 18, analyzing particles ranging in size from colloidal (>2 µm) to very fine silt size particles (<10 µm). The mobile particle concentrations and particle size distributions are controlled by the filtrating properties of the respective aquifer and well construction design. Van Beek et al concluded the following: 1) Extracted groundwater contains particles of multiple sizes; 2) Particle composition is governed by the aquifer matrix;

• Mechanical (particulate clogging)

3) Particles mobilize toward the well screen during pumping; and

• Chemical encrustation and corrosion (chemical precipitate clogging)

4) Not all particles pass through the well bore during extraction.

• Biological (microbial corrosion and slime clogging) These issues have been discussed at length in a wide array of available literature and will not be reiterated here 10, 7, 16,. However, several important facts regarding well clogging should be noted: 1) These three forms of well clogging are interactive4. 2) Well operational factors can play a key role in the clogging development17. 3) The infiltration of sand and other fine particulates remains one of the most common forms of well clogging7. Identifying the correct form(s) of well clogging is key to providing effective remediation. The traditional approach in assessing well clogging is visual inspection (video logging). This is a good first step, but too often the only diagnostic step. Without a complete diagnosis of the clogging cause, there is risk of continual and ineffective re-development. Recently, other more effective methodologies to identify and define the form of clogging are moving to the forefront, and include: • Particle counter technology17 to identify mechanical clogging, which was first used in the water supply industry in the early 1980s where it demonstrated its utility in understanding well screen clogging and purging effects13. • Field or advanced laboratory methods4, 7 to identify chemical and biological processes contributing to clogging. SME’s 2014 well redevelopment program included a particle counter analysis of suspended particles in the relief well discharge water to identify potential mechanical clogging conditions. The analysis of data collected by the Chemtrac LaserTrac Particle Counter PC3400 confirmed that the relief well clogging was particulate in nature.

ISSN 1944-9836 - Association of State Dam Safety Officials

This work has been ground-breaking in its analysis of particle movements in wells and the resultant clogging potential under a myriad of groundwater discharge conditions. Specifically, in the Netherland’s Noordbergum wellfield analysis, Van Beek and Stuyfzand observed that wells which started and stopped with regularity (daily or even more frequently) were statistically less prone to particle clogging than wells that were operated continuously. Further, wells with particle clogging issues were able to recover some yield and improve performance when shifted from a continuous to an intermittent operating mode17. De Zwart1 and Timmer, et al11 hypothesized that fine-grained particles are retained and accumulate in the well bore and that over time this zone of accumulation expands outwards. Ultimately, the smaller spaces between the sand grains in the well bore, known as pore-throats, become constricted by the retained particles and hinder the flow of water to the well3, 12. In many cases, starting and stopping a pump surges the flow of water to the well and in so doing purges accumulated particles from the well bore17. Conversely, constant pumping conditions may produce an unwanted increase in particle accumulation, ultimately leading to a reduction of flow from the well. Figure 3 illustrates a particle counting curve for a newly constructed water production well located in central New Jersey, pumping at 880 gpm. As shown, the total particle count per minute (cpm) rises to around 30,000 total particles on the pump surge. Approximately 20 minutes after pump start-up, the particle count discharge curve has settled back into a gradual decline; within 90 minutes after pump start-up, the discharge curve is essentially flat. Also plotted on Figure 3 are the counts per minute of five of 10 particle size classes that make up the total particle count line. As expected, the smallest particles (2-5 µm) make up the largest population of clogging particles identified, and particle counts systematically grade lower as particle size increases. The particle counter data show that the surge created upon starting a large pump has sufficient erosional capacity to remove particles of all sizes from the well bore area and that the erosional THE JOURNAL OF DAM SAFETY | VOLUME 15 | ISSUE 4 | 2018


The Packer-Purge System was tested in each relief well under three different methods of packer-purging (listed below in order of least aggressive to most aggressive method): 1) Static Packer-Purging (Static Purging) – Wherein an inflated packer halts the flow in the well (through packer inflation) and then instantaneously releases it. 2) Air Surging ( Juttering) – Air is surged through a bypass in the inflated packer, thereby pushing the water column several feet down the well. Figure 3. Typical Particle Count Discharge Curve for Groundwater Supply Well.

capacity diminishes with pumping time, supporting Van Beek’s and Stuyfzand’s assertion. The relief wells at the Powerhouse, while not operating with pumps, are groundwater extraction instruments, continuously discharging to their sub-grade header piping. As a result, the potential for particle accumulation and, in turn, well clogging is significant.

PHASE I TRIAL OF PACKER-PURGE SYSTEM AT SCHAGHTICOKE The Phase I Trial of the Packer-Purge System for the three Powerhouse relief wells was designed and constructed to investigate the premise that intermittent surging of the relief wells using natural gradients could remove (purge) clogging particles and restore well yield, thus reducing pore-water pressures. The Packer-Purge System was designed to accomplish the following: 1) Halt the flow in the respective wells, either individually or in combination (depending on the resultant pressure response), by inflating a packer.

3) Pump Assisted Purging – Natural pore-water pressures are maximized as a result of removing (via pumping) water above the packer before release. Once outfitted, the relief wells were then run through a systematic series of packer-purging tests, both individually and in combination, to evaluate the individual and collective response of the wells to the packer-purging methods. Data on transducer pressures, particle counts, and flow rates at the weir were collected throughout the Trial.

RESULTS OF PHASE I TRIAL OF THE PACKER-PURGE SYSTEM™ During the three-day Phase 1 Trial, each of the Packer-Purge System methods of well purging yielded positive results, in varying degrees, as observed in three critical areas: 1) Reducing pore-water pressures in the aquifer beneath the Powerhouse; 2) Restoring measurable flow to the weir; and 3) Removing particles from the well bore. The net results and impact of the Phase I Trial in these three areas are as follows.

A. Pore-Water Pressure Reduction

2) Allow a pressure condition to stabilize beneath each inflated packer. The amount of pressure that builds up will depend on the method being used (described later).

The plot in Figure 4 illustrates the pore-water pressures recorded in the VWPs (corrected for barometric pressure) before, during, and after the time of the Trial.

3) Release the packers to create an instantaneous surge into each well, thereby purging particles from the well bore, and restoring flow to the well.

An overall reduction in pore-water pressures of approximately one foot on average was measured by VWPs P1, P2, and NM3. Following the end of the Trial, the pore-water pressures measured by the respective VWPs were below Design Basis Value and comparable to pressures realized in and around 2012. The return to gradually increasing pore-water pressures following the Trial is evident in the right-side of the Figure. As a result, the recommendation was made to develop and construct an Automatic Packer-Purge System to control pore-water pressures.

Each packer assembly was outfitted with the following: a. An inflatable packer and appurtenances to inflate the packer via an air compressor. b. A pressure recording transducer situated below the packer to measure water pressure response when the packer was inflated. c. A submersible pump to remove water above the inflated packer. d. A manifold to direct and control air flow into and out of each packer assembly.



I S S N 1944-9836 - Association of State Dam Safety Officials

Figure 4. VWP Pore-Water Pressures: Before, During and After Phase 1 Trial

B. Flow to the Weir Over the course of the three-day Trial, flow across the weir increased from a starting point of approximately 48 gpm before packer purging was initiated to approximately 53 gpm post-packer purging. This increase in flow over the Trial period showed a positive impact of the System’s methodology.

C. Particle Removal from the Relief Wells Figure 5 is a plot of the particle counts per minute for relief well RW2 as a result of the three packer-purging methods applied to the well during the Trial. (Note, the other two relief wells responded with similar particle count patterns during each of the purging methods.) The lower left-hand corner of the plot indicates that under prepurging conditions (i.e. normal well operation) total particle counts in the wells ranged from only 40 to 90 cpm. In our experience, such a low value is indicative of a clogged well. Immediately following a packer-purging event (when the most particles are being removed from the well) particle removal rates ranged from 3,000 cpm as a result of the Static Packer Purge (least aggressive) to around 12,000 cpm as a result of the Pump Assisted Purge (most aggressive). As expected, the more aggressive purging methods produced a greater reduction in pore-water pressure and a greater increase in flow to the weir. These data indicate that the use of naturally occurring hydraulic gradients can be an effective means of mobilizing particles from the well bore and thus reducing well clogging. Finally, as previously mentioned, in the 2014 well redevelopment program, formation materials were being evacuated from the well bore6, potentially creating voids in the gravel pack. In contrast, upon completion of the Phase I Trial, no sediment had accumulated in the well sumps as a result of the cumulative Packer-Purging Methods applied during the Trial. ISSN 1944-9836 - Association of State Dam Safety Officials

Figure 5. Typical RW-2 Particle Counts During Phase 1 Trial Program.

This difference in outcomes between the 2014 pumping program and the Phase I Trial is important because it confirms that while clogging particles are clearly being removed from the well bore via the Packer-Purge System, the well gravel pack is not being mobilized, thus maintaining integrity of the well bore. As a result, the System would appear to be a far less destructive and therefore more sustainable method of well purging.

AUTOMATED PACKER-PURGE SYSTEM™ INSTALLATION, OPERATIONS AND PRELIMINARY RESULTS The Phase 1 Trial findings resulted in the client authorizing the design and construction of an Automated Packer-Purge System (in place since fall of 2016) to determine if this approach can successfully lower and then maintain the desired pore-water pressures, and thus foundation stability, in the long term.

A. Automated Packer-Purge System Design and Installation In the fall of 2016, SME designed and installed an Automated PackerPurge System at the Schaghticoke Development Powerhouse. The System, illustrated in Figure 6, consists of an Allen Bradley Human Machine Interface (HMI) programmed to 1) Operate the automatic valves on the manifold that control the flow of compressed air, and 2) Regulate the packer-purging method air pressures. The flow of compressed air is directed through the manifold into the well packers to operate the three Packer-Purge System methods discussed earlier. Air relief valves on the manifold allow for instantaneous release of compressed air. Manual valves allow for the relief wells to be operated independently, should purging of individual wells be necessary.



Figure 6. Automated Packer-Purge System Control Panel

The PLC has been designed to allow for the ability to 1) Select the type of packer-purging method, 2) Schedule the frequency of the method, and 3) Control the intensity of each method. For example, multiple back-to-back-purges (halting and releasing the flow to the well in rapid succession) are considered a more intense purging method than a single daily purging event. Packer Inflation Safety Precautions: To ensure that packers cannot stay inflated for periods longer than programmed, i.e., eliminating the potential for the relief wells to remain pressurized for longer than programmed intervals, redundant safety routines are built into the PLC, including: Packer-Purge method timers, fail safe “Open� valves (in the event of power loss), and audible alarms. The PLC records data from each packer-purge event on a SM card so that the Automated System operations can be tracked and analyzed.

B. Automated Packer-Purge System Operation and Preliminary Results The operation of the Automated Packer-Purge System began in Static Purge with one purging cycle each day simultaneously in all three wells to gently initiate the particle purging process. Over time, multiple back-to-back purges were programmed to increase the purging intensity. Pore-water pressure readings from the VWPs were downloaded weekly to assess the ability of the Automated PackerPurge System to maintain desirable pressures. Figure 7 illustrates the pore-water pressure trends in VWP-2 observed over the period of Static Purge operation. The blue-trend line illustrates the gradual increase in pore-water pressure prior to the start-up of the Automated System, followed by the green-trend line illustrating the gradual decrease in the pressure gradient upon initialization of the Automated System. Note, the trend in decreasing pore-water pressure was interrupted by a series of rainfall events that raised the tail-water elevation, resulting in a significant increase in pressures in the VWPs (the grey line in the yellow highlighted area). These data indicate that the tail-water elevation directly impacts pore-water pressures at the relief wells. Accordingly, we corrected the VWP data, thereafter, to compensate for this relationship and allow for a continuous evaluation of the Automated System’s performance. The red line on the right side of



Figure 7. Static Purge Pressure Response in VWP-2 at Start-up of Automated Packer-Purge System

the plot illustrates the data corrected for tail-water elevation. Overall, a month of Static Purge operation served to 1) Reverse the long-term trend in increasing pore-water pressures and 2) Reduce pore-water pressures in all VWPs (based on corrected data by around 0.3 feet). In late October 2016, the Packer-Purge System was switched to Juttering, again employing a single purge of low pressure to initiate the program. Again, Juttering pressures and schedules were gradually increased over time to achieve greater pore-water pressure reductions. As previously observed during the Phase I Trial, there was an increase in flow to the weir along with each reduction in pore-water pressure. Figure 8 illustrates the pore-water pressure trends observed in VWP-2 from October 2016 through March 2017 resultant from Juttering. As illustrated on the right-hand side of the Figure, the gradual

Figure 8. Impact of Juttering on Pore-Water Pressure Response in VWP-2 in Automated Packer-Purge System

I S S N 1944-9836 - Association of State Dam Safety Officials

increase in Juttering intensity generated a succession of significantly larger downward steps in pore-water pressure. Ultimately, a reduction in pore-water pressure of nearly one foot was observed as a result of a single Juttering event, far outstripping the impact of the Static Purge Method.

C. Comparing the Automated Packer-Purge System to Previous Relief Well Redevelopment Programs Table 1 presents a summary of the key findings from the 2016 Pilot Program and compares them with the results of the 2011 and 2014 relief well redevelopment programs. The data reveal that the Packer-Purge System accomplished comparable improvements in pressure reduction and weir flow when compared to the more aggressive redevelopment programs of 2011 and 2014. Equally important, the effects of the Packer-Purge System are 1) long-lasting (due to repeated operation) and 2) absent gravelpack erosional issues using the three Packer-Purge System methods. As discussed, gravel pack erosion leads to well inefficiency and, in the worst case, well or formation collapse.

D. Permanent Installation of Automated PackerPurge System Once all pore-water pressures were reduced some 2.7 feet below pre-Static Purge conditions, the Automated Packer-Purge System was taken offline and retrofitted to become a permanent installation, including PLC code efficiencies, new air hoses and encasements, well head installations (to withhold uplift pressures) and some stainless steel downhole replacement parts. In June 2017, the Automated System went back online in Juttering, and, to date continues to control relief well pore-water pressures below the Design Basis Value at the Powerhouse and support flow to the weir.

SUMMARY AND CONCLUSIONS Research in the Netherlands on well clogging and other advances in well clogging assessment are opening the door to new approaches in the area of relief well maintenance and operation at dam/powerhouse sites. The Packer-Purge System discussed herein is one example of how existing methodologies can be brought together to build a new application, and provide an innovative and cost-effective approach to extend relief well life and effectiveness.

TABLE 1 Summary of Relief Well Redevelopment Programs at Schaghticoke Development Powerhouse 2011-2016 Redevelopment Program Components Redevelopment Program

Post-Redevelopment Effects

Program Duration (days)

Redevelopment Approach

Requisite Equipment

VWP Pressure Reduction(feet) (3)

Flow Rate Gain at Weir (gpm)

Formation or Gravel-Pack Erosion

2011 Parratt-Wolff (5)


Bio-acid; Overpumping at 40 gpm; Swabbing

Crane/pump equipment (2)


+0 (1)

Feet of sediment accumulation by 2014

2014 Clogging Assessment SME/Parratt-Wolff (6)


Over-pumping at 130 gpm; Swabbing; Jetting

Crane/pump equipment (2) Particle counter



Formation erosion noted - jetting program halted

2016 Phase I Trial of Packer-Purge System - SME (6)


Packer-Purging: Static, Juttering and Pump Assist

Portable hand tools, Particle counter



None noted

2016 Automated Packer-Purge System – SME (ongoing)

240 (as of March 2017)

Packer-Purging: Static and Juttering

Portable hand tools, Particle counter




Notes: 1. Weir flow rate measurements are approximate. 2. Proximity to overhead power lines required shutting down the Powerhouse during redevelopment. 3. Average pressure reduction of VWP P-1, P-2 and NM-3.

ISSN 1944-9836 - Association of State Dam Safety Officials



The positive impacts noted above demonstrate that taking advantage of natural gradients when purging relief wells has the potential to serve as a viable long-term strategy to maintain flow rates to the weir and keep pore-water pressures below the Design Basis Value. Equally important is the fact that low-gradient well purging generates minimal erosion/disturbance of the well-screen gravel-pack area, which has the added advantage of maintaining the wells in the long-term. Finally, only hand tools are required to install or inspect the System so costs are reduced in comparison to traditional well redevelopment techniques and there are no overhead restrictions. At every dam/powerhouse site, safety is the overriding goal. The Packer-Purge System to date has been proven to be more than the quick fix offered by traditional well redevelopment. The System is a promising tool for reducing relief well clogging and porewater pressures and a sustainable strategy for long-term relief well maintenance.

ACKNOWLEDGEMENTS Brookfield Renewable for the opportunity to conduct the pilot program of the Packer-Purge System and permission to present these results, Allen Saucier, PE at AHS Engineering, and my colleagues at SME for their guidance and support.

REFERENCES 1) De Zwart, A.H., 2007. Investigation of clogging processes in unconsolidated aquifers near water supply wells. Ph.D. thesis, Delft Techn. Univ., the Netherlands. 2) Duke Energy, 2000. Memo on Results of Relief Well Pumping Tests, Modeling, and Site Observations Schaghticoke Hydro Development. February 14, 2000. 3) Logan, B.E., 1999. Environmental Transport Processes. John Wiley & Sons, New York. 4) McEnroe, Rebecca, P.E., Superintendent, Sudbury Water District, Sudbury, MA, and Savas Danos, General Manager, Panton-McLeod-Americas, Groton, MA, 2017. Elimination of Chronic Total Coliform Presence in a Gravel Packed Well Through Enhanced Well ReDevelopment. New England Water Conference, April 5, 2017. 5) Parratt-Wolff, 2011. Memo on Redevelopment Program Summary. 6) Sevee & Maher Engineers, Inc., 2014. Memo on Schaghticoke Relief Well Redevelopment Program Summary, June 20, 2014.

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I S S N 1944-9836 - Association of State Dam Safety Officials

7) Smith, Stuart A. and Allen E. Comeskey, 2010. Sustainable Wells – Maintenance, Problem Prevention, and Rehabilitation. CRC Press, Taylor and Francis Group. 8) Soil Metrics LLC, 2016. 2015 Dam Safety and Surveillance Monitoring Report, Schaghticoke Development, March 11, 2016. 9) Soil Metrics LLC, May 14, 2017. E-mail titled “Updated Schaghticoke Pore Pressure Plots - through April 11, 2017”. 10) Sterrett, Robert J., Ph.D., RG, 2007. Groundwater and Wells Third Edition. Library of Congress Cataloging-in-Publication Data. 11) Timmer, H., J.D. Verdel, and A.G. Jongmans, 2003. Well clogging by particles in Dutch wellfields. J. AWWA, 95 (8), 112118. 12) Tufenkji, Nathalie and Menachem Elimelech, 2004. Correlation Equation for Predicting Single-Collector Efficiency in Physicochemical in Saturated Porous Media. Environmental Science and Technology, 38 (2), pp 529–536. 13) Van Beek, C.G.E.M. and W.F. Kooper, 1980. The clogging of shallow discharge wells in the Netherlands river region. Groundwater, 18 (6), 578-586. 14) Van Beek, C.G.E.M., 1984. Restoring well yield in the Netherlands. J. AWWA, 76 (10, 66-72. 15) Van Beek, C.G.E.M., 1989. Rehabilitation of clogged discharge wells in the Netherlands. Quart. J. Eng. Geol., 22 (1), 95-80. 16) Van Beek, C.G.E.M., 2012. Cause and Prevention of Clogging of Wells Abstracting Groundwater from Unconsolidated Aquifers. KWR Watercycle Research Institute Series. 17) Van Beek, C.G.E.M. and P.J. Stuyfzand, 2012. Cause and Prevention of Clogging of Wells Abstracting Groundwater from Unconsolidated Aquifers. Chapter 8. Well incrustation and well design criteria. KWR Watercycle Research Institute Series. 18) Van Beek, C.G.E. M., et al., 2010. Concentration and size distribution of particles in abstracted groundwater. Water Research Elsevier 44 (2010) 868-878.

Bruce A. Fowler, M.S., C.G. Sevee & Maher Engineers, Inc. 4 Blanchard Road Senior Hydrogeologist/Principal Cumberland, Maine 04021 (207) 829-5016

A principal with Sevee & Maher Engineers, Inc., Bruce Fowler has over three decades of experience in the water resources industry, specializing in hydrogeology, geochemistry, and geotechnical issues. Mr. Fowler is a leading expert on well construction and redevelopment in complex environments, pumping test analysis, and trouble-shooting low-producing or inefficient wells to identify rehabilitation methods or well usage strategies to resolve yield problems. He received a Bachelor of Science in Geology from Boston University and Master of Science in Environmental Engineering from the University of Vermont.

Colin O’Connor

Brookfield Renewable 13 Powerhouse Rd Project Manager Schaghticoke, New York 12154 (518) 615-9355 Colin.OConnor@brookfieldrenewable. com Colin O’Connor became interested in engineering during his time as a land surveyor. Having completed a degree in mechanical engineering in 2015, he now works for Brookfield Renewable as a project manager.

Stephen Rabasca, P.E.

Soil Metrics LLC 12 Farms Edge Road President and Principal Cape Elizabeth, Maine 04107 Geotechnical Engineer (207) 767-2192 Stephen Rabasca has over 35 years of geotechnical consulting experience. His firm, Soil Metrics LLC, focuses on seepage and stability analyses of dams and embankments, the development of geotechnical instrumentation and monitoring for hydroelectric facilities and landfills and the engineering behavior and monitoring of soft clay deposits which are prevalent in the northeastern United States. He received his BS in Civil Engineering from the University of Maine in 1981.

ISSN 1944-9836 - Association of State Dam Safety Officials




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I S S N 1944-9836 - Association of State Dam Safety Officials


ABSTRACT The U.S. Army Corps of Engineers designed a bedrock grouting program for Dale Hollow Dam in Celina, Tennessee, and contracted with Rembco Geotechnical Contractors, Inc., to perform the work. The design required a suite of grout mixes exhibiting excellent stability, low bleed, and low pressure filtration over a wide range of viscosities. The contractor spent significant time developing six different mix formulations for the project. The primary focus of this effort was to meet the specified performance requirements using a single water to cement (W:C) ratio for the grout mixes. The use of a single W:C ratio was critical in being able to swiftly change the batches from one mix design to another while minimizing wasted grout and simplifying field quality control. This paper describes some of the complexities and considerations in this grout mix development process.

BEDROCK GROUTING AT DALE HOLLOW DAM Dale Hollow Dam, located near Celina, Tennessee, was completed by the United States Army Corps of Engineers (USACE) in 1943 primarily for flood control of the Obey River. Like many other dams built on karst geology, characterized by sinkholes, caves, seeps, and springs, Dale Hollow Dam has experienced seepage through the bedrock foundation over the years. A significant effort was made by the USACE to understand the geology and seepage pathways, with data from a program of borings, piezometers, dye tests, and geophysical surveys. The latest phase of the investigative work was an exploratory grout program.

ISSN 1944-9836 - Association of State Dam Safety Officials

Rembco was awarded the contract for exploratory drilling and grouting in September 2012. The project consisted of installing an exploratory grout line adjacent to the Dale Hollow Dam switchyard. The scope of work included: • core drilling with logging, • optical televiewing of select core holes, • dye testing and water pressure testing in 10-foot stages to evaluate the existing bedrock conditions, • grouting in 20-foot stages utilizing pneumatic packers to isolate zones, and • continuous computer monitoring and real-time display of flow and pressure for each stage, along with the calculated apparent hydraulic conductivity. Although this exploratory program included most elements of a full-scale dam grouting program, the extent of the effort was limited. Eighty holes were cored to an average depth of 85 feet, and approximately 23,000 cubic feet of grout was injected. The relatively small scale of this effort dictated the use of small grout batching equipment, rather than the typical pairing of a bulk cement silo with a high-capacity, automated batching system. Bagged cement and other grout components were hand-fed into a skid-mounted colloidal mixer.



GROUT MIX SPECIFICATION The project specifications required six stable grout mixes (A through F), with specific ranges of viscosity as shown in Figure 1. Although USACE specified the rheological parameters for each mix, the formulation of the grout to meet the requirements was left to the contractor.

Changing the water:cement (W:C) ratio for each mix is the most common source of quality problems in small batching operations. Rembco recognized that significant operational advantages could be gained if all mixes shared the same W:C ratio. A single W:C ratio would enable the crew to quickly change from one mix to another in response to varying hydraulic conductivity within a borehole. It would also significantly reduce waste and simplify field quality control. Furthermore, if it was possible to combine the water, bentonite, and VMA into a single slurry that could be added to a fixed volume of cement for all mixes, only the superplasticizer would be variable, dramatically simplifying the batching process. These concepts formed the basis of the mix development effort.


Figure 1. Project specifications for grout mix.

The term “stable” is often used to describe grout with very little separation, or bleed, when held stationary. In this context, stability also refers to the ability of the mix to retain water when pressure is applied. The grout mix specification required very stable mixes with extremely low bleed and pressure filtration. The time limit for reaching initial set was readily achievable for a fluid grout, except for one “accelerated” mix. Specified viscosities for each of the six mixes were in very narrow ranges, which are difficult to achieve in a laboratory setting and even more difficult to repeatedly reproduce in the field. Based on prior experience formulating stable cement grouts, the contractor recognized that the following three materials would be needed to produce the specified grout: • Bentonite – primarily for bleed control • Viscosity Modifying Admixture (VMA) – primarily for pressure filtration • Superplasticizer – to tailor the viscosity to the specified ranges Along with the cement and water necessary for cementitious slurry, the ratios of the three above additives would be adjusted to achieve the six required mixes.

MIX DEVELOPMENT CONSIDERATIONS Mixing grout with five hand-batched components is complex in a small-scale production environment. Bentonite yield is more effective and predictable if it is pre-hydrated, which requires storage tanks, transfer pumps, and additional mixing assets. VMA and superplasticizer are used in very small amounts and are easier to accurately measure in liquid form. In addition, the specification mandated the ability to change from one mix to another within two minutes, which could result in changing volumes for each mix component.



Full development of the final mix formulations was a three-stage process. This process began in the contractor’s laboratory with numerous tests in a controlled environment. Trial batches of the resultant mix designs were then produced in the shop yard using a production-type mixer. Finally, each mix design was produced and adjusted on the project site using the actual production equipment and material sources. Equipment used for each phase of the mix development is shown in Figure 2. The most difficult and lengthy part of the process was the laboratory phase, where different proportions of the basic components were tested to produce a stable grout. Weeks of small-scale formulation trials were conducted before producing five of the grout mixes that met the USACE’s rheological requirements for the project. The sixth mix, which had an additional requirement of an accelerated initial set-time, continued to present problems and is addressed later in this paper. The laboratory testing led to a good understanding of what types of materials were required to achieve the specified parameters, and how those ingredients worked together to influence the results. Graphs were generated as parameters were varied, to facilitate interpretation of the data and interpolation to desired results. An example of one such graph is shown in Figure 3. The next step in the mix formulation process was to batch larger trial runs with a production-type mixer. The initial results were expected to differ from the lab results due to variables in the batching method, temperature, and available water sources. Testing of these larger trial batches proved that the grout characteristics were different from the laboratory batches, and required adjustment to meet the specifications. However, these adjustments were simplified by the data and knowledge gained in the earlier development of the mix designs in the laboratory. The final step in the process was to produce and test each of the mix designs at the project site with the batching equipment and material sources to be used during production grouting. Additional changes were required to attain the specified grout characteristics. However, given the extensive development effort prior to mobilization, minor adjustments could be made in the field, allowing for a quick transition into production grouting. I S S N 1944-9836 - Association of State Dam Safety Officials

Figure 2. Equipment used in the various phases of mix development.

Figure 3. An example of parametric analysis used to formulate grout mixes.

THE ACCELERATED-SET MIX The project specifications required one fluid grout mix, with a Marsh funnel flow between 55 and 70 seconds, to have an accelerated initial Vicat needle set time (ASTM C191) of less than one hour. The mix was still subject to the stringent bleed and pressure filtration ISSN 1944-9836 - Association of State Dam Safety Officials

requirements. An accelerated-set mix was needed to prevent uncontrolled flow of grout into the river if significant flow paths were encountered. Although a thicker mix would work in open conduits, the thinner fast-flowing grout was needed to ensure that smaller features could be treated. THE JOURNAL OF DAM SAFETY | VOLUME 15 | ISSUE 4 | 2018


Many different types of accelerating admixtures were tested, but none of the products could accelerate such a fluid mix to reach an initial Vicat set in less than an hour, even at extreme doses. One of the accelerating admixtures tested in the grout mix was calcium chloride (CaCl). The admixture slightly accelerates the set time, but more importantly, it enhances the thixotropic nature of the grout mix. Several minutes after being removed from the shear of mixing and

pumping, grout with calcium chloride undergoes a rapid viscosity increase to form a gel that is resistant to flow. ASTM C1611 is the standard test method for slump flow of self-consolidating concrete. The standard slump cone is filled and removed; then the diameter of the resulting “puddle� of concrete is measured. This style of test was adapted to evaluate the thixotropy

Figure 4. Decreasing slump flow at increasing hold times, for grout with varying amounts of CaCl.


Figure 5. Cone is filled and removed

Figure 6. Spread diameter is measured

Figure 7. Spread after 0 and 20-minute hold

Figure 8. Spread after 60-minute hold


I S S N 1944-9836 - Association of State Dam Safety Officials

of the grout mix on a relative basis. Instead of a full-size slump cone, testing was conducted using a styrene cone of similar aspect ratio, but with a base diameter of 7.5 cm. A number of cones were filled and allowed to sit undisturbed for variable intervals until the cone was removed and the diameter of the grout spread was measured.

interact with each other to attain desired characteristics. This insight is essential as many external factors can influence the rheology of the grout, including mixing method, material sourcing, temperature, and water pH. Trial mixes and test data also provide a basis for optimizing productivity and improving quality control of the mixing operation.

Figure 4 shows data from tests of the accelerated mix with 0%, 2%, and 4% CaCl (by weight of cement). The grout has some viscosity gain over time even without the CaCl because of the thixotropic nature of the base mix, but the effect is considerably amplified with increasing percentages of CaCl. Pictures of the tests are shown in Figures 5 through 8. Based on these test results, the contractor requested that the 1-hour Vicat set requirement for the accelerated mix be waived, and presented the 4% addition of CaCl to the grout as an alternative. USACE agreed that this satisfied the purpose of the accelerated-set mix and approved the change.

CONCLUSION Modern grouting projects often require high-performance cementitious grouts, with extremely low bleed and pressure filtration, and control of viscosity. A grouting contractor’s commitment to in-house development of grout mixes is expensive, but pays off with an understanding of how various grouting materials and additives

H. Clay Griffin

President Rembco Geotechnical Contractors, Inc. P.O. Box 23009 Knoxville, TN 37933 (865) 671-2925 After 12 years in the field of underwater acoustics, Clay Griffin switched to the glamorous world of grouting, ground improvement, and foundation support by joining Rembco Geotechnical Contractors as Vice President of Operations. Taking over as President in 2001, he still enjoys occasionally getting his hands dirty formulating specialty grouts for challenging projects.


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Jeff Bradley, Ph.D., P.E., D.WRE, President | 503.485.5490 Marty Teal, P.E., P.H., D.WRE, F.ASCE, Vice President | 858.487-9378 ISSN 1944-9836 - Association of State Dam Safety Officials



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I S S N 1944-9836 - Association of State Dam Safety Officials

Is the Elephant Even In the Room? – Communicating Flood Risks Related to Dams AMANDA J. HESS KALLIE BAUER JAMES E. DEMBY PAUL G. SCHWEIGER Design criteria for dams are frequently based on hazard potential. of hazard potential is comprehensive in its broad consideration of FEMA (2004) defines hazard potential as the possible adverse potential hazards, in practice hazard potential classification is often incremental consequences that result from the release of water or defined much more narrowly. Frequently, the hazard potential and 140,000 stored contents due to failure of the dam or mis-operation of the hazard potential classification of a dam are defined by simulating a dam or appurtenances. dam failure and the This definition goes resultant impacts of 140,000 120,000 on to state that the the corresponding impacts may be for a flood wave in the 120,000 defined area downstream reach downstream. 100,000 of a dam from flood The sudden release of 100,000 Sunny Day Breach Sunny Day Breach waters released through stored water results PMF Breach PMF Breach 80,000 spillways and outlet in discharges that far PMF Non‐Failure 80,000 PMF Non‐Failure 100 Year Event Non‐Failure works or waters released exceed normal flows 100 Year Event Non‐Failure 60,000 by partial or complete or even extreme flood failure of the structure. It events. 60,000 40,000 also mentions that there For dams that are may be impacts for an classified as high hazard 20,000 area upstream of the dam 40,000 potential, regulatory from effects of backwater 0 spillway design floods flooding or landslides 6 8 10 12 14 16 18 are often very extreme Time (Hours) 20,000 around the reservoir and very rare storm perimeter. Although Figure 1 Relative Magnitude of the Common Regulatory Base Flood (the 100-year events such as the flood), the PMF, and a dam failure event. this published definition Probable Maximum 0 Outflow (cfs)

Outflow (cfs)





ISSN 1944-9836 - Association of State Dam Safety Officials


Time (Hours)






Flood (PMF) or a percentage of the PMF. The PMF is defined as the flood that may be expected from the most severe combination of critical meteorologic and hydrologic conditions that are reasonably possible in the drainage basin under study (FEMA, 2004). Again, the focus is on flows that greatly exceed the magnitude of flood events that are much more frequent or are commonly referenced by the general public, such as the 100-year flood. Figure 1 shows the relative magnitude of the common regulatory base flood (the 100-year flood), the PMF and a dam failure event for a representative dam. Much of the hydrologic and hydraulic design and analysis effort for a dam is spent on evaluating extreme events and, in a sense, neglecting the consideration of some of the other flood risks associated with dams. Dams can induce flood risks in a range of flood and non-flood conditions. This paper will introduce and present relevant case studies for some often-overlooked ways dams can induce flood risks. Available and potential means for better communicating this flood risk will be considered.

OPERATIONS-INDUCED FLOOD RISKS Most dams have spillways to allow flows from a wide range of rainfall and flood events to be safely passed around the dam without destroying the structure. If the rate of flow is controlled by mechanical means, such as gates, it is considered a controlled spillway. If the geometry of the spillway is the only control, it is considered an uncontrolled spillway (FEMA, 2004). Dams also have outlet works, a collection of conduits regulated by gates or valves that are used for controlled releases of impounded water from the reservoir. They are designed to safely draw down the reservoir under emergency conditions, for controlled releases to meet downstream water rights and for dam maintenance. Considering both of these means of releasing water, operations-induced flood risks are flood risks that

result from either operating or failing to operate controlled spillways or outlet works. This could occur in either flood or non-flood conditions. Any additional discharge of water from a dam during a flood event has the potential to cause additional flooding in the downstream reach. If the discharge capacity of the outlet works is small compared to the drainage area, and if the spillway is an uncontrolled spillway, the incremental impact of releasing water during a flood may be insignificant. However, for some dams, and in just the right discharge conditions, opening a valve or gate may cause flood impacts to properties that would not have been otherwise flooded. Although there seems to be no official definition of “safe channel capacity�, safe channel capacity can be considered the discharge that a given channel can sustain without adverse impacts to property. The U.S. Fish and Wildlife service has informally defined safe channel capacity as the discharge into the receiving river or stream which threatens inhabited buildings, established recreational areas, or overtopping of public roads. In other words, flows larger than the defined safe channel capacity would cause impacts. Releasing additional water when the channel is already flowing at the safe channel capacity will have an incremental impact. This scenario occurred during the above-average spring runoff in Colorado in 2015 at a dam more than 100 feet high impounding a reservoir of nearly 100,000 acre-feet (Figure 2). While the uncontrolled spillway was passing a relatively large discharge for the downstream canyon, the reservoir level was continuing to increase. Although the spillway and outlet works are not commonly operated concurrently, the owner opened the outlet works to attempt to further control the reservoir level rise. Releasing about 200 cfs through the outlet works resulted in an approximate discharge of 1500 cfs in the outlet channel. As shown in Figure 3, this caused overbank flooding and concern downstream. In some cases, dams are capable of making discharges that can impact property even during non-flood conditions. This is often the case for dams with gated spillways for which the capacity of the spillway exceeds the safe channel capacity. At Greenwood Lake Dam located in the North Attleboro National Fish Hatchery in Massachusetts, it was reported that the exercising of gates during a routine inspection resulted in the release of water that began to impact downstream roads. Local emergency responders arrived onsite to investigate the cause. Because of this incident and the potential for similar incidents to occur at other dams, the U.S. Fish and Wildlife Service developed



I S S N 1944-9836 - Association of State Dam Safety Officials

to the development located both upstream around the reservoir rim as well as downstream along the banks of the Salmon Falls River, operating the reservoir prior to and during flood events is comparable to walking a tightrope attempting to strike a balance between contributing to flooding upstream and contributing to flooding downstream.

PERCEIVED OPERATIONSINDUCED FLOOD RISK Because the general public and some floodplain managers and emergency responders do not understand the design basis for dams during flood events, flooding can wrongly be attributed to proper operations. For some dams, the reservoirs may commonly be operated well below the uncontrolled spillway crest, and spillway flows are rare occurrences. Downstream residents grow accustomed to having the in-stream flows controlled by the outlet works. During flood events, when the reservoir pool rises to the level of the uncontrolled spillway crest, and the channel begins to experience much larger discharges, the public may look upstream and perceive that the flooding is caused by the dam or that the dam is not operating as intended.

a policy requiring all of their significant and high hazard potential dams to have a documented safe channel capacity. As suggested by the FEMA definition, in some cases impacts are possible around the rim of the reservoir due to backwater flooding. This potential hazard is most common for flood control dams. Flooding can be exacerbated by not releasing water prior to or during a flood event. Milton Three Ponds Dam, located in Milton, New Hampshire has gates and flashboards to assist with controlling the reservoir level that receives runoff from over 100 square miles. Due ISSN 1944-9836 - Association of State Dam Safety Officials

During the 2013 floods in Colorado, many spillways were activated that typically are dry. Button Rock Dam, located upstream of Lyons, Colorado has a drainage basin of over 100 square miles. Given the location on the North St. Vrain River, it is common for the spillway to operate during the spring and early summer months to pass outflow from the reservoir; however, flow during this period is typically less than 1,500 cfs. The peak discharge through the Button Rock Dam spillway during the 2013 flood was estimated to be 10,000 cfs. This amount of flow is unusual, exceeds the estimated 100-year flood discharge of 7,400 cfs, and caused significant damage to roads, bridges, and structures along the river flood plain (Figure 5 and Figure 6).



Figure 5 Button Rock Dam spillway

Figure 7 RCC emergency spillway structure at Left Hand Valley Dam

Figure 8 Overview of spillway flow and downstream floodplain below the Left Hand Valley Dam

Figure 6 Washed-out road downstream of Button Rock Dam spillway

During the 2013 flood event, there was concern the spillway was eroding and could breach, releasing the contents of the reservoir and compounding the damage and public safety threat already occurring. With road access to the dam destroyed, inspectors were flown in by helicopter and found significant surficial erosion of the spillway channel had occurred down to bedrock but there was no concern of failure. The fact that the dam was functioning successfully did not eliminate the flooding concern, and highlighted the differing priorities among dam safety professionals and floodplain managers. Flood events can also cause spillway flows in areas that are normally dry, such as reaches below off-stream dams. These dams are normally fed by upstream river diversions. During flood events, diversions from larger watersheds may disproportionately increase inflows to the dam causing spillway flows and unexpected downstream flooding.



During the 2013 floods in Colorado, some ditch diversion or control structures were destroyed and stream flows were uncontrollably redirected into ditches feeding reservoirs. Heavy runoff into the reservoir from the contributing drainage basin combined with uncontrolled inflow from the Left Hand Ditch quickly filled Left Hand Reservoir, causing the emergency spillways to operate. A combined flow of approximately 200 cfs flowed over the RCC emergency spillway, and the earthen secondary spillway structures for two days (Figure 7 and Figure 8). Flow from the spillway discharged through a subdivision and golf course below the dam and eventually into Boulder Reservoir. The spillway structures suffered only minor damage and operated as intended, but these flows created dangerous conditions and caused damage to the downstream developed areas.

CHANGE IN FLOOD RISKS DUE TO DAM MODIFICATION As dams in the United States age and dams undergo rehabilitation or repair to address condition issues or bring dams into compliance with current design standards and regulations, some dam modifications can change flood risk. A common dam safety deficiency is insufficient spillway capacity. Rehabilitating a dam to safely pass I S S N 1944-9836 - Association of State Dam Safety Officials

An increase in downstream flooding due to significantly increased spillway crest length has resulted in at least one lawsuit in recent years. While the larger spillway capacity reduced the risk of dam failure due to overtopping, the design failed to consider that downstream property owners would experience larger discharges more frequently. To guard against this type of downstream flood risk, spillways can be designed with two stages to replicate discharges for more frequent flood events (first stage), with the increase in spillway crest length occurring only for rare reservoir levels and flood events (second stage). Figure 9 shows a labyrinth weir with one cycle designed to replicate reservoir outflows up to approximately the 100-year flood event.

the spillway design flood can involve enlarging the spillway to increase the spillway discharge capacity. An unintended outcome from an enlarged spillway can be an increase in the discharge due to the reduction in reservoir attenuation with the increased spillway capacity.

Another common method to modify dams to safely pass spillway design floods is to raise the top of dam elevation to prevent dam overtopping and allow more discharge through the spillway. This option has the potential to increase the consequences of failure due to providing more flood storage. It also may present additional flood risk to properties on the reservoir. Many regulatory agencies require engineers and owners consider these additional flood

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risks in the permit approval process and possibly require mitigation such as obtaining flood easements or purchasing property. For example, the dam permit application for Pennsylvania requires the dam owner to provide “proof of title or adequate flowage easements” as part of their permit application process. Other seemingly minor dam modifications, such as the placement of fill, may also impact flooding for lesser events. The degree of floodplain impacts from this activity is considered and is often controlled by local floodplain management regulations. Communities that participate in the National Flood Insurance Program (NFIP) must require permits for proposed construction and, depending on local floodplain management regulations and the designated special flood hazard area in the project site, may require that the project be shown to have no increase to the elevations of the regulatory flood (often the 100-year or base flood). In some cases, when dams no longer serve a purpose, dam removal or decommissioning is considered. Without the dam, the attenuation provided by the dam is lost and the resulting larger downstream flows can result in increased flooding. To address this concern in the highly developed floodplains of New Jersey, New Jersey Dam Safety requires dam removal designs to address flood risk for a suite of events. Figure 10 shows a staged weir that was designed to mitigate a dam removal in New Jersey. Regulating (and discouraging development within) the larger floodplain that ignores attenuation provided by non-flood control dams can minimize some of these concerns and simplify the mitigation required as part of dam modifications or removals.



The focus of the NFIP is shifting from identifying flood hazards to helping communities understand flood risks and take action to reduce flood risks (FEMA, 2011). The traditional Flood Insurance Rate Maps (FIRMs) and Flood Insurance Studies (FIS) were focused on identifying flood risks. In some areas these studies were based on approximate methods. The floodplains for these streams are designated as Zone A special flood hazard areas. Other streams are studied by detailed methods which establish base flood elevations, or 100-year water surface elevations for the reach. The floodplains for these streams are designated as the Zone AE special flood hazard area. In some cases, additional hydraulic analyses called encroachment analyses are completed to establish the regulatory floodway. A “Regulatory Floodway” is defined as the channel of a river or other watercourse and the adjacent land areas that must be reserved to discharge the base flood without cumulatively increasing the water surface elevation more than a designated height (44 C.F.R. 59.1). In other words, construction within the regulatory floodway is subject to strict regulation. Although dams are an important feature in floodplains, dams are not consistently depicted or consistently analyzed in the development of these studies. The analyses completed to establish the floodplain and regulatory floodway were completed over a period of approximately forty years, beginning in the late 1970s. The older studies may rely on outdated methodologies, models or other input data. The level of detail incorporated into the studies varies widely. The methods used to consider dams varies from completely neglecting the presence of the dam to incorporating detailed reservoir routing techniques and hydraulic relationships. While these maps may indeed assist communities in identifying flood risks, they do not convey many of the specific flood risks identified within this paper. Another type of map that is intended to communicate flood risk related to dams is the dam break inundation map. These maps depict inundation extents from various failure scenarios and are included in the Emergency Action Plan of a dam to assist emergency responders with warning and evacuation in the event of an impending dam failure. While these maps are prudent to convey the flood risk from dam failure, they are not useful in conveying some of the other flood risks identified within this paper.

I S S N 1944-9836 - Association of State Dam Safety Officials

Compounding the need for additional ways to communicate flood risk, some dams are located on intermittent streams or unmapped drainage outside of the mapped FEMA floodplain. Because the FEMA floodplain is the most commonly referenced method for conveying flood risk to property owners, the absence of a FEMA floodplain in the area downstream of a dam may result in property owners who are not aware of their flood risk. Figure 11 is dam break inundation map that shows the dam break inundation zone in pink and the 100-year FEMA floodplain in yellow, highlighting the fact that the dam break inundation zone is not located within a special flood hazard area. While not shown on the figure, the area that would be inundated for a spillway activation event would be much smaller than the dam break inundation zone, but would still inundate areas outside of the 100-year FEMA floodplain. No standard products exist to communicate the potential for flood hazards from dam releases or spillway flows. Current efforts undertaken by Colorado and the authors of this paper have identified a systematic method for ranking dams in Colorado by risk factors that could lead to downstream flooding. As part of the same project, simplified safe channel capacity mapping has been developed for several dams. Preparing additional mapping and making the database and mapping available to a group of floodplain managers and emergency responders is being considered as a pilot study. However, these efforts have led to a more comprehensive discussion of dams and flood risk and the question remains as to who is responsible for taking on this difficult task. With dams operating within their design limits, is managing the downstream flooding risk the responsibility of the floodplain managers and emergency managers? These efforts to define the responsibilities and develop methods to better communicate flood risk will be documented in a future article in the Journal of Dam Safety. For now, dam safety professionals are stewards of information and knowledge that can be used to quantify some of these risks. It is therefore our duty as dam safety professionals to recognize and communicate comprehensive potential flood risks to our flood risk management partners, and to be leaders working to actively reduce dam safety risks.

ISSN 1944-9836 - Association of State Dam Safety Officials

ACKNOWLEDGEMENTS The authors would like to thank the following individuals and organizations who contributed to this article: Chris Adams, P.E. Civil Dynamics Tim Carney, P.E., New Hampshire DES Jim Gallagher, P.E., New Hampshire DES Brad Iarossi, P.E., U.S. Fish and Wildlife Service Ryan Knarr, P.E., Pennsylvania DEP Bill McCormick, P.E., Colorado DWR Darin Shaffer, P.E., New Jersey DEP

REFERENCES 44 C.F.R. ยง 59.1 (2017) Commonwealth of Pennsylvania, Department of Environmental Protection, Bureau of Waterways Engineering and Wetlands, Application for a Dam Permit. Rev. 1/2013. 3 pp. FEMA, Federal Guidelines for Dam Safety, Glossary of Terms, 2004. 28 pp. FEMA, Operating Guidance 3-11, Communicating Flood Risk with Risk MAP Datasets and Products, July 11, 2011. 20 pp.



Amanda J. Hess, P.E., CFM H&H Group Manager Gannett Fleming, Inc. 207 Senate Avenue Camp Hill, PA 17011 (717) 763-7211

Ms. Hess is Hydrology and Hydraulics Group Manager in the Dams and Hydraulics Section of Gannett Fleming, Inc. Amanda received her bachelor’s and master’s degrees in civil engineering from the Pennsylvania State University. She has over 18 years of experience working on dams, flood control projects, and water supply systems performing a wide range of hydraulic and hydrologic analyses. She is responsible for leading a team of engineers to perform hydrologic and 1-, 2- and 3-D hydraulic analyses for water resources projects and regularly instructs courses on hydrologic and hydraulic modeling. As a CFM, Amanda also routinely evaluates projects for floodplain management considerations.

Kallie E. Bauer, PE, CFM Dam Safety Engineer CO Dam Safety Branch 810 9th Street, Suite 200 Greeley, CO 80631 (970) 352-8712 x 1218

Kallie Bauer is a dam safety engineer for the Colorado Dam Safety Branch of the Division of Water Resources in the Greeley Office. Her responsibilities include inspection, evaluations, and emergency preparedness coordination for dams in the Cache La Poudre Basin and South Platte Basins. She received her bachelor’s degree in civil engineering from Penn State University and master's degree in civil engineering from Colorado State University. Kallie joined the Colorado Dam Safety Branch in April 2013 after 15 years in consulting engineering.



James E. Demby, Jr., PE

Senior Technical and Policy Advisor National Dam Safety Program Federal Emergency Management Agency 400 C Street 3SE-3001 Washington, DC 20472-3020 (202) 646-3435 Mr. Demby is the senior technical and policy adviser for the FEMA National Dam Safety Program. He advises FEMA’s deputy federal insurance and mitigation administrator for mitigation on matters pertaining to national dam safety. Mr. Demby is a professional engineer registered in Virginia and has worked for the U.S. Army Corps of Engineers. His work for the Corps included Richmond Floodwall, Gathright Dam, James R. Olin Flood Protection Project, Walter F. George Dam Rehabilitation, and the Portugues Dam. He also served as the dam safety officer for the US Forest Service National Headquarters. Mr. Demby joined FEMA in April 2007.

Paul Schweiger, P.E., CFM Vice President Gannett Fleming 207 Senate Avenue Camp Hill, PA 17011 (717) 763-7211

Paul Schweiger is Vice President and Manager of Gannett Fleming’s Dams and Hydraulics Section. Paul received his bachelor’s and master’s degrees in civil engineering from the University of New Brunswick, Canada. He has over 34 years of experience working on dams and flood control projects. His technical specialties include conducting dam assessments, designing new dams, and dam rehabilitation. He is an approved FERC facilitator for performing potential failure modes analysis exercises for dams, serves on Independent External Peer Review panels for several United States Army Corps of Engineers dam and flood control projects, and is currently serving on the Board of Consultants for the Oroville Dam Spillways Recovery Project.

I S S N 1944-9836 - Association of State Dam Safety Officials

Yahoola Creek Dam, Dahlonega, GA

Rehabilitation and Upgrades / New Dam Design / Inspections and Evaluations Potential Failure Modes and Risk Analysis / Planning and Permitting Construction and Contractor Support Services / Instrumentation and Monitoring Emergency Action Plans / Operations and Maintenance Plans and Support

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ISSN 1944-9836 - Association of State Dam Safety Officials




award winners, all of whom will be honored at the 2018 Awards Ceremony during Dam Safety ’18 in Seattle.

The ASDSO Board of Directors approved a Fiscal Year 2019 Action Plan and Budget at its summer meeting in Sacramento in June. The organization’s mission is advanced through a long list of projects and activities — 146 specific projects to be exact — identified in the action plan, which runs from July 2018 to June 2019. A $2.57 million budget was approved to support the plan through June of 2019.

While in California, Board members were treated to a field trip to the Oroville Dam to view the massive rehab effort. Thanks go to Sharon Tapia and Mutaz Mihyar from the CA DWR, Division of Safety of Dams, and Matt Murray, CA DWR for hosting.

Activities of twenty-five committees, task groups and interest groups are supported by this budget, ranging from long-standing programs that support student outreach and the technical journal committees, to newer initiatives including the Young Professionals Interest Group, the Public Safety at Dams Committee, and the Media Relations Committee.

Two new case studies focusing on the failures at Tous Dam and Marshall Lake Dam were added to Both case studies, as well as the other case studies and lessons learned on the website, include relevant photographs, videos and resources to support the description and background information provided. Thank you to researcher Ryan Schoolmeesters, P.E. and expert reviewers Mark Baker, P.E. (Tous Dam) and Alon Dominitz, P.E. (Marshall Lake Dam).

The Board also closed out and put a stamp-of-approval on the Fiscal Year 2018 Action Plan year and endorsed an impressive list of annual


Kneeling: (From L to R): Hal Van Aller (MD), Alon Dominitz (NY), Charles Thompson (NM), Ed Knight (LA). Standing (From L to R): Matt Murray (CA DWR), Ken Smith (IN), Lori Spragens (ASDSO Director), Dusty Myers (MS), Jon Garton (IA), Mark Ogden (ASDSO Tech Specialist), Nathan Graves (WY), Bill McCormick (CO), Greg Paxson (AdCom Vice Chair, Schnabel), Yohanes Sugeng (OK). Not pictured: Roger Adams (PA, our photographer).



I S S N 1944-9836 - Association of State Dam Safety Officials


Tous Dam (Spain)

Marshall Lake Dam (Colorado)

Tous Dam is located in the Province of Valencia in the southeast corner of Spain, near the Mediterranean Coast. Tous Dam failed only 4 years after completion of the original construction in 1982, when an intense storm cell during a heavy rain event delivered 22 inches of precipitation, or about the equivalent of the average total annual rainfall, within a 24-hour period.

A comprehensive, detailed historical review of Marshall Lake Dam revealed four downstream slope failures in its past; something that the current engineers responsible for oversight didn’t know. The information provided a better understanding of the embankment construction methods, highlighted the long history of embankment instability, and revealed outstanding and unresolved dam safety concerns. This knowledge, coupled with the recently observed and documented embankment movement, generated sufficient concern about the stability of the dam to warrant immediate action by the dam owner and implementation of a focused long-term monitoring program. Without the comprehensive review, the minor dam crest depression and embankment movement might have continued to be brushed aside as a “normal nuisance condition,” which could have paved the way for another, and potentially more devastating, slope failure at Marshall Lake Dam.

Though the dam failure was an undeniably regrettable event, significant changes in dam safety standards, emergency communications and risk management were borne out of the experience that have and will continue to shape flood management policy and strategies in Spain and throughout the European Union. In many ways, the Tous Dam failure had similar impacts on the Spanish and European emergency management community as the Teton Dam failure had on dam safety policy in the United States.




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REPORT ON USACE INFRASTRUCTURE INITIATIVE STAKEHOLDER SESSIONS May 2 -- ASDSO was invited to attend the US Army Corps of Engineers’ (USACE) Infrastructure Initiative Water Resources Stakeholder Session in DC. ASDSO, represented by past president John Moyle, joined over 20 other stakeholder organizations at the feedback session. The session was hosted by USACE Director of Civil Works, James Dalton, and Assistant Secretary of the Army R.D. “Rickey” James. The USACE goal was to seek and secure long-term reforms in the way infrastructure projects are funded, delivered and maintained, and to get feedback on the Administration’s Legislative Outline for Rebuilding Infrastructure in America. The outline is available here - INFRASTRUCTURE-211.pdf John Moyle is the director of the Division of Dam Safety and Flood Control for the New Jersey Department of Environmental Protection.

ASDSO MEMBERS AND PARTNER ORGANIZATIONS HELP TO COMMEMORATE NATIONAL DAM SAFETY AWARENESS DAY On May 31st, the nation joined in commemorating National Dam Safety Awareness Day, remembering the lessons learned from past dam failures, pushing for strong dam safety programs and advocating for investment in America’s critical infrastructure. ASDSO participated through an educational subpage on its website ( Thanks to the help of our dedicated members and partner organizations, the page received more than 700 unique page views during May, with the average visitor spending at least 5 minutes on the page. On May 31st, ASDSO shared awareness messages through its Facebook, Twitter, Instagram, LinkedIn and YouTube accounts using #DamSafetyDay. ASDSO posts alone received more than 60 shares allowing us to reach a broader, more diverse audience.

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D Thank you to the many individuals, companies, municipalities and other entities that made a public effort to raise awareness of dam safety issues. Although difficult to thank all national participants by name, we would like to acknowledge those organizations that participated through a coordinated effort with ASDSO: American Society of Civil Engineers Ayres Associates, Inc. City of Raleigh (North Carolina) Colorado Division of Homeland Security and Emergency Management Federal Emergency Management Agency Freese And Nichols, Inc. Indiana Department of Homeland Security International Association of Emergency Managers International Water Power and Dam Construction City of Lansing (Michigan), Lansing Fire Department and Russ Hicks Mississippi Environmental Quality Department My Green Montgomery (Montgomery County Department of Environmental Protection, Maryland) National Association of State Fire Marshals National Watershed Coalition National Weather Service North Dakota State Water Commission, Karen Goff, P.E. New Hampshire Department of Environmental Services New Jersey Department of Environmental Protection Pennsylvania Department of Conservation and Natural Resources Schnabel Engineering, Inc. Skagit County, Washington Steve Durgin, Natural Resources Conservation Service Virginia Department of Conservation and Recreation Water Power Magazine

The City of Lansing’s Office of Emergency Management (Michigan) joined with ASDSO to demonstrate the dangers of low head dams through ‘sacrificing’ an empty canoe to the boil of a local dam.

Chief Micheal Toben, Lansing Emergency Management Chief, being interviewed about low-head dam safety as part of National Dam Safety Awareness Day.

NEW LOW-HEAD DAM AWARENESS VIDEO NOW AVAILABLE - BE A DAM CHAMPION A new youth-focused low-head dam awareness video, ‘Be A Dam Champion’, is available for use through the ASDSO YouTube channel. The video features Leah Pritchett, an American drag racer. In the video, Pritchett explains that since the moment she first hit the throttle in a Junior Dragster at 8 years old, she only had one ambition, to be a champion. Leah helps to explain the dangers of low-head dams and urges others to be a champion by avoiding this ‘opportunity for disaster.’



I S S N 1944-9836 - Association of State Dam Safety Officials


V IS I T US AT BOO T H # 317

S TATE - OF -THE - AR T DATA ACQ U I S ITION & MANAGE ME NT FOR DAM OWNE RS C A N A R Y S Y S T E MS.C O M | 6 0 3.5 26 .98 0 0 ® ISSN 1944-9836 - Association of State Dam Safety Officials



The Indiana Silver Jackets created this video through a partnership with the Indiana Department of Homeland Security, the Indiana Department of Natural Resources, WFYI Public Media, ASDSO and Leah Pritchett. We encourage you to share this video with family, friends, co-workers and local community groups. Sharing the link through an email or a

Leah Pritchett, an American drag racer, urges others to be a champion by avoiding low-head dams.

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social media post will go a long way towards raising awareness about this danger and helping to prevent further drownings.

SPEAKERS BUREAU The ASDSO Speakers Bureau is made up of volunteers with experience and expertise in dam engineering, best practices, dam safety and public education. The volunteers are the ‘face’ of dam safety and serve as the key connection between local communities and expert knowledge. Speakers Bureau volunteers make presentations before student and community groups to raise awareness of careers in dam engineering and of dam safety issues,

Five middle school children, led by Benjamin IsraelDevadason, created and distributed fliers regarding the dangers at low head dams to their schoolmates.

Russ Hicks shared the video ‘Over, Under Gone’ with attendees at the Michigan Watershed Summit. His table included paddles with the names of victims mentioned in the video.



I S S N 1944-9836 - Association of State Dam Safety Officials

Register Now for DamSafety 2018! Join us for the 35th Annual Dam Safety Conference hosted by the Association of State Dam Safety Officials (ASDSO). Dam Safety 2018 is the premier conference dedicated to the dam and levee safety industry. • 900+ Dam and Levee Safety Professionals • 100+ Presentations • 34 Sessions • 100+ Exhibitors & Sponsors • 2 General Sessions • 2 Field Trips • 1 Specialty Workshop • Hours & Hours of Networking Opportunities

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ISSN 1944-9836 - Association of State Dam Safety Officials



including safety of dams and safety around dams, and to provide general education on the role of dams in society. Presentations are tailored for the needs of the audience and can cover a wide range of topics, and ASDSO provides materials. Learn more about the Speakers Bureau at http://DamSafety.Org/SpeakersBureau or email ASDSO Communications Manager Katelyn Riley (kriley@ Thank you to our recent Speakers Bureau volunteers: Russ Hicks (Returning the Rapids to Eaton Rapids), Bill McCormick (CO Division of Water Resources), Kallie Bauer (CO Division of Water Resources), Clint Oman (NJ Department of Environmental Protection) and Benjamin Israel-Devadason (Gannett Fleming). We appreciate your time and efforts.

UPDATED ASDSO MEMBERSHIP DIRECTORY Clint Oman teaches dam safety through a dam model that allows students to control weirs and emergency spillways.



The PDF version of the ASDSO membership directory was updated in June and is available through the members-only section of

I S S N 1944-9836 - Association of State Dam Safety Officials

ASSOCIATION OF STATE DAM SAFETY OFFICIALS The PDF directory includes instructions on accessing the online, interactive membership directory that is available through the ASDSO Portal.

TRANSITIONS AT ASDSO HEADQUARTERS In June, we said goodbye to Sarah McCubbin-Cain. Sarah retired after 20 years of service to ASDSO. Sarah has been our resource and library manager, and most all of you know her as the go-to person for any type of bibliographic search or document inquiry support that you’ve needed. We will miss Sarah and wish her well in her future endeavors. Sarah plans on doing a lot of traveling and spending more time with her family and friends. We wish her the best! Please direct any future inquiries to Katelyn Riley (

ISSN 1944-9836 - Association of State Dam Safety Officials



MEMBER NEWS Tim Schaal, state representative for South Dakota, retired at the beginning of June. Thanks to Tim for his years of service to dam safety! Jeanne Goodman, chief engineer with the Water Rights Program, is now the state representative. Mario Fusco, Environmental Engineer at the MI Department of Environmental Quality, has been appointed as Michigan's state representative to ASDSO.

Benefits Associated with the USACE Levee Portfolio’. The report shares their current understanding of the flood risks and benefits associated with the portfolio of levee systems within the USACE Levee Safety Program. The United States Army Corps of Engineers has made significant updates to the National Levee Database (NLD). The new website is

ASDSO member Gregory J. Daviero has joined Schnabel’s board of directors. Gregory heads the Albany, New York, area office, where he supports a portfolio of federal, state, municipal and industrial clients in the water, wastewater, and dam engineering markets.

PARTNER NEWS The American Society of Civil Engineers (ASCE) has released the 2018 Missouri Infrastructure Report Card. Missouri’s approximately 5,529 dams received a grade of D-. The poor grade reflects the fact that 1,123 High and Significant Hazard Potential Dams in the state are exempt from any dam safety regulation. The American Society of Civil Engineers (ASCE) has released the 2018 Kansas Infrastructure Report Card. Kansas’s approximately 6,400 dams received a grade of C-. The U.S. Army Corps of Engineers Levee Safety Program has released a new document, ‘Levee Portfolio Report - A Summary of Risks and



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I S S N 1944-9836 - Association of State Dam Safety Officials

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ISSN 1944-9836 - Association of State Dam Safety Officials



Advertiser Index | Place your ad by calling Ross Brown (859) 550-2788, Toll Free: (855) 228-9732 or

Advertiser . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Page URL Advanced Construction Techniques . . . . . . . . . . . . . . . . . . . . . . . . . 2

AECOM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Bergmann Associates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 Canary Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 CARPI USA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 D’Appolonia Engineering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Findlay Engineering Inc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 FLO-2D Software, Inc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 Gannett Fleming, Inc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 GENTERRA Consultants, Inc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 Geokon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 Global . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Gomez & Sullivan Engineers, D.P.C.. . . . . . . . . . . . . . . . . . . . . . . . . . 28 Hayward Baker Inc . . . . . . . . . . . . . . . . . . . . . . . . . . Inside Back Cover

HDR Engineering, Inc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Hydronia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 Hydroplus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Mead & Hunt, Inc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Measurand Inc. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Moretrench . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 OBG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 RST Instruments Ltd. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 Schnabel Engineering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Sealite . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Stantec Consulting Services, Inc . . . . . . . . . . . . Inside Front Cover

Tighe & Bond . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 TREVIICOS Corporation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 WEST Consultants, Inc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Worthington Products Inc . . . . . . . . . . . . . . . . . . . . . . . . . . Back Cover

Worthington Products Inc. - Tuffbuoy . . . . . . . . . . . . . . . . . . . . . . . . 1



I S S N 1944-9836 - Association of State Dam Safety Officials

ISSN 1944-9836 - Association of State Dam Safety Officials



Boat Barriers

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