CIVIL WORKS
R&D Va l u e t o t h e N a t i o n
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CIVIL WORKS R&D: VALUE TO THE NATION Ta b l e o f C o n t e n t s
Introduction: R&D Value to Nation’s Infrastructure . . . . . . . . . . . . . . . . . . . 3 Guide to Booklet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 History of Civil Works R&D since 1700s . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Highlights: Civil Works R&D Value to the Nation . . . . . . . . . . . . . . . . . . . . 9 Thin Layer Placement of Sediment . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Real-Time Kinematic Global Positioning System (RTK GPS) . . . . 13 Water Hyacinth Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Vegetated Coastal Dune Resilience . . . . . . . . . . . . . . . . . . . . . . . . . 17 Automatic Information System Analysis Package (AISAP) . . . . . . 19 Lock Operations Management Application (LOMA) . . . . . . . . . . . 21 Novel Materials for Infrastructure . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Structural Health Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Soil Stabilization - Biopolymer Technology . . . . . . . . . . . . . . . . . . 27 Sand Boil Mitigation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Engineering with Nature for Coastal Wetlands . . . . . . . . . . . . . . . . 31 Credits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
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INTRODUCTION: R&D VALUE TO NATION’S INFRASTRUCTURE
Through its Civil Works missions, the U.S. Army Corps of Engineers supports the national economy, community resilience, and human and ecosystem health through six mission areas: Navigation, Flood & Coastal Risk Management, Ecosystem Restoration, Hydropower, Recreation, and Regulatory. Inherent in these missions is efficient and effective design, operation, maintenance, and rehabilitation of our nation’s vast portfolio of infrastructure, including: • Hidden infrastructure such as coastal, intercoastal and inland navigation channels; • Natural features that the Corps can create and enhance to provide engineering and ecosystem services such as wetlands, beaches, and vegetated streambanks • Traditional infrastructure such as dams and levees, amongst others. The Corps’ Engineer Research & Development Center (ERDC) conducts basic and applied research for innovative Corps design and management of our Nation’s infrastructure. These research advancements have facilitated risk-informed decision-making, streamlined operations, enhanced ecosystems through optimizing sediment management, and Engineering with Nature, to name a few. Research conducted by ERDC has helped the Corps build infrastructure resilience, including innovative materials and techniques to repair and extend the life of infrastructure, analyses and tools that provide real-time data for more effective vessel operations, and quantification of benefits by leveraging missions to efficiently provide navigation, flood risk reduction, and ecosystem services.
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GUIDE TO BOOKLET
This booklet provides examples of how R&D has improved the design, assessment, operation and maintenance, and rehabilitation of our nation’s water resources infrastructure. For each example, the cross-cutting impact is identified as it affects the Corps’ three largest missions – Navigation (NAV), Flood & Coastal Risk Management (FRM), and Environmental (ENV) missions. NAV - Navigation R&D programs conduct research to extend the life of existing navigation infrastructure; improve navigation operations such as multi-modal freight flow optimization; optimize design and management of resilient navigation systems; and develop electronic Navigation (eNavigation) capabilities. FRM - Within Flood & Coastal Risk Management, R&D develops tools to conduct lifecycle analysis of water resource infrastructure, including risk and uncertainty; manage resilient coastal, estuarine, and watershed systems, including earthen, structural and hybrid “graygreen” infrastructure; and enable effective emergency management disaster preparation, response, and recovery. ENV - Environmental R&D is developing methods to quantify ecosystem goods and services within Corps project assessments; characterize the physical, chemical and biological variations affecting degradation in coastal environments; improve capabilities to design and implement aquatic ecosystem restoration in urban regions; and optimize management of Threatened & Endangered and Invasive Species. In the following examples, the relative cross-cutting impacts of each R&D advancement are qualitatively identified by a color-coded gauge located in the lower portion of page as follows: In the example to right, NAV, FRM, and ENV are equally represented.
100% NAV
FRM
ENV
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CIVIL WORKS R&D TIMELINE 1775-1927 1802 Congress created the Corps of Engineers and the U.S. Military Academy
In the 20th century, the Corps became the lead federal flood control agency and significantly expanded its civil works activities
1775 George Washington appointed the first Army engineer officers
Throughout the 1800s, the Corps built coastal fortifications, surveyed roads and canals, eliminated navigational hazards, explored and mapped the Western frontier, and constructed buildings and monuments in the nation’s capital
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1927-1931
Great Flood of 1927
1929 Establishment of the U.S. Army Waterways Experiment Station
1931 1st Outdoor Model Carved in Soil Illinois River Backwater
1932-1941
1st Erosion Model -Bonnet Carre
1st Cutoff Model -Greenville Bends
1936-1965 48 projects and $8 million in funding for environmental research
1942-1949
1942 Pioneered Water Quality Research
Normandy Beach Landing
CW R&D Applied to Military Operations
Caisson Model D-Day Breakwater Tests
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1950-1963
Niagara Falls Model
Methods to Control Aquatic Plants
Mississippi River Basin Model
Harbor Models
1964-1983 • Transition to hybrid hydraulic modeling • Water Resources R&D • Environmental Water Quality R&D
1966 Dredged Material R&D
1973 Old River Control Structure and the Mississippi River Flood
Ecological Research Program
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1984-1999 Ship Tow Simulator
Chesapeake Bay Tidal Estuary Physical and Numerical 3D Model Bonneville Fish Ladder Model
Olmsted Lock and Dam Modeling Construction Productivity Advancement Research (CPAR) Program
Repair, Evaluation, Maintenance, and Rehabilitation (REMR) Program
2000-PRESENT • Eulerian-Lagrangian Agent Method (ELAM) Fish Tracking Model • Adaptive Management of Endangered Species resulted in $30M/Yr savings • MR&T Lower Mississippi River Conservation Plan for endangered species • Coastal Armoring Research (CORE-LOC) • Sediment Modeling and Management Practices
Coastal Storm Modeling
Post-Katrina Analysis and Interagency Performance Evaluation Taskforce (IPET)
Cross-mission benefits realized through Regional Sediment Management and Engineering with Nature
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HIGHLIGHTS: CIVIL WORKS R&D VALUE TO THE NATION
PROBLEM
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The Water Resources Development Act (WRDA) of 1986 dictated that material dredged in the Mobile Bay navigation channel in Alabama be disposed of in an Offshore Dredged Material Disposal Site located as far as 40 miles from the north end of the bay, thus limiting the dredge type to only ocean going vessels and nearly tripling the cost of dredging in the bay.
$2 $6
WRDA 1986 INCREASED DREDGING COSTS
FROM
TO
PER CUBIC YARD
SOLUTION
In 2012, the Corps’ Mobile District pursued a onetime demonstration of TLP in Mobile Bay that included 9 million cubic yards of sediment. ERDC used several data collection and modeling tools to determine sediment transport directions once placed there.
$6
TLP COST SAVINGS MILLION PER YEAR FOR MOBILE BAY
IMPACT
Modeling and monitoring results brought a unanimous decision to support in-bay placement as an environmentally acceptable alternative to ocean disposal. A permit was issued on June 30, 2014, allowing in-bay placement of Operations & Maintenance material from Mobile Ship Channel.
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THIN LAYER PLACEMENT OF SEDIMENT
Thin Layer Placement (TLP) involves the intentional placement of thin layers of sediment, such as dredged material, in an environmentally acceptable manner to achieve a target elevation or thickness. TLP projects can utilize dredged sediment as a valuable resource to create, maintain, enhance or restore ecological function. A large Regional Sediment Management strategy was created for Mobile Bay that included constructing a TLP project using sediment from the federally-authorized Mobile Harbor Navigation Project (MHNP), thereby keeping valuable sediment in the regional system. The MHNP contains a 45-feetdeep by 400-feet-wide channel that extends 29 miles from the northern portion of the bay to the entrance that is regularly dredged to maintain navigable depths, and consists of mostly fine-grained sediments that are dredged to maintain channel depth and width. Along with several other strategies employed in the bay, the TLP project helped decrease overall cost of dredged material management due to its shorter haul distance over taking material offshore to an Ocean Dredged Material Disposal Site.
NAV
FRM
ENV
PROBLEM
Heavy construction generally requires some form of earth movement (whether it be grading, clearing, cutting or filling) or dredging for navigation channels. Prior to RTK-GPS, geodetic surveys were performed to map height and position for subsequent topographic or hydrographic surveys to support engineering design. Surveyors then interpreted the designs to lay out the project site for construction crews.
SOLUTION
RTK-GPS replaces time-consuming surveys with a system that requires fewer people to operate and delivers real-time 3D positions with half-inch accuracies.
IMPACT
RTK-GPS is easy to use, accurate and reliable, allowing the GPS industry to offer products in excess of $1 billion a year to customers worldwide. These systems are the primary positioning tools for topographic and hydrographic surveying and mapping, and are the principal 3D positioning devices for earth moving equipment, dredges and marine lift cranes, aerial photogrammetric and LIDAR aircraft, and agricultural operations.
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REAL-TIME KINEMATIC GPS
USACE invented Real-Time Kinematic GPS (RTKGPS) to create 3D real-time horizontal positioning information for hydrographic survey vessels and dredges. RTK-GPS also minimizes tide induced errors of one-foot vertical for computing dredge quantities. The technology far exceeded expectations, delivering real-time 3D positions with half-inch accuracies, while serving as a basis for additional development under the Construction Productivity Research Program (CPAR). Under CPAR, USACE entered a joint development project to integrate its RTK-GPS system with Caterpillar’s Computer Aided Earthmoving System. This project yielded a system that provides the equipment operator with a real-time cut and fill computer display that is fully integrated to computer design files. Today, RTK-GPS systems are used worldwide as primary positioning methods for surveying and mapping.
RTK-GPS
- REAL-TIME 3D POSITIONING - IMPROVED ACCURACY TO 1/2” - USED WORLD-WIDE AS PRIMARY SURVEYING & MAPPING SYSTEM
NAV
FRM
ENV
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WATER HYACINTH CONTROL
Native to tropical South America, water hyacinth entered the United States at the 1884 International Cotton Exposition in New Orleans, Louisiana, where blooming plants were distributed as “souvenirs” because of their beautiful purple flowers. Water hyacinth is now established in freshwater habitats throughout the southeast, as well as California, Washington, Hawaii and Puerto Rico. Water hyacinth is an aggressive, invasive floating plant, often described as one of the world’s worst weeds due to its rapid growth rate and ability to form large interlocking mats of vegetation. This matting can impede navigation, and clog flood control structures and irrigation intakes, negatively impacting recreation and other water uses. Problematic dense growths overtake native plants and degrade water quality, thus creating the need for controls.
NAV
FRM
ENV
PROBLEM
Dense water hyacinth populations can weigh as much as 400 tons per acre, clogging USACE navigation channels, locks and flood control structures. Large water hyacinth mats form a physical barrier on the water surface and hinder recreational activities, such as boating, fishing and swimming. Public health issues are also a concern as dense growths provide mosquito breeding habitats and conditions for mosquito-borne illnesses.
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$704
INVESTMENT FOR THOUSAND RESEARCH
SOLUTION
Through the USACE Aquatic Plant Control Research Program, ERDC developed numerous effective biological and chemical management strategies that selectively control water hyacinth with minimal impact to the environment and native, non-targeted species.
$124 APPLICATION COST 1974-2013 MILLION
FOR COASTAL LOUISIANA
IMPACT
Long-term management of invasive aquatic plants is economically beneficial. Economic analysis in 2018 demonstrated that water hyacinth ecosystem management benefits greatly exceeded research dollars spent to investigate control of this nuisance species. Initial research investments ($704K) to develop management tools generated $4.2B in benefits to boating-dependent businesses, water treatment facilities and recreationists.
$4.2
IN NUISANCE CONTROL BILLION BENEFITS
FOR COASTAL LOUISIANA
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VEGETATED COASTAL DUNE RESILIENCE Coastal dunes are common along our nation’s coastlines, acting as a first line of defense against storm-induced flooding and wave impacts to coastal regions. Naturally-formed dunes and vegetation serve as a dynamic buffer between land and sea that grows during calm conditions from wind and ecological processes and erodes from waves and water levels during extreme events. Constructed dunes are low-cost, features that reduce the impacts of major storms and limit damages to nearby infrastructure, providing flood protection benefits. During Hurricane Sandy, communities with federal beach projects that included dunes experienced less inland flooding and infrastructure damage. Following construction, dunes can continue to grow naturally through the use of sand fencing and grass planting. Ongoing ERDC research is developing integrated wave, water, wind and ecological process models to quantify how natural systems evolve, and how management actions like sand fencing installation, dune grass planting and beach widening can reinforce natural processes to enhance dune re-building following storms, while enabling more efficient management of our nation’s coastlines.
NAV
FRM
ENV
PROBLEM DUNES
- FIRST LINE OF DEFENSE FOR STORMS - NATURAL, ECOLOGICAL DYNAMIC BUFFER - REDUCED HURRICANE SANDY DAMAGES
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USACE requires improved guidance on how to best design and manage federal beach and dune projects to work constructively with natural processes and promote resilient coastlines. Hurricane Sandy highlighted the benefits of dunes in reducing coastal flooding and protecting vulnerable infrastructure. Ongoing research will identify optimal design parameters that efficiently use costly sand resources and natural vegetation while maximizing coastal protection.
SOLUTION
ERDC uses laboratory, field and numerical modeling approaches to improve understanding of the relevant natural processes controlling the transport of sand between beaches and dunes. This research uses stateof-the art observational tools with numerical models to understand complex interactions between waves, wind, plants and people that shape coastal systems.
IMPACT
ERDC research can increase our ability to promote more resilient coastlines by protecting people and property during storms and developing capabilities that allow more efficient management our nation’s sand resources.
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PROBLEM
USACE navigation managers need quantitative assessments that capture how vessels traverse the physical confines of navigation channels in terms of vessel positioning, speed and tracking information collected by the U.S. Coast Guard. The Automatic Identification System (AIS) provides this technological data and is mandated for nearly all commercial vessels operating in U.S. waters.
SOLUTION
The U.S. Coast Guard and ERDC developed the AISAP to allow users to immediately run targeted queries across multiple years of data within U.S. waters. Users can generate traffic density maps, vessel track line overlays, and summary statistics for trip counts, vessel types and other detailed analytics.
IMPACT
AISAP allows navigation managers to understand how infrastructure is being used and how environmental factors change vessel traffic patterns; can replay vessel collisions to investigate root causes and aid in engineering studies; enables quantification of vessel wake wave energy to understand erosion forces and coastal resilience impacts; and drastically reduces the need for site visits, channel surveys and other expensive field data collection.
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AUTOMATIC IDENTIFICATION SYSTEM ANALYSIS PACKAGE
The Automatic Identification System Analysis Package (AISAP) is a web-based tool for acquiring, analyzing and visualizing real-time and archival data from the U.S. Coast Guard, developed by ERDC for use by USACE and decision makers at all levels of the organization. AISAP users can search for any and all vessels in an area during a specific time or limit their search to specific vessels during a given time range. Archived AIS data include time, speed over ground, direction, vessel draft, beam, length and vessel type. The AISAP allows unprecedented access to quantitative, statistically robust measures of navigation project performance over time through analysis of historical vessel records. The tool supports informed decision making and optimized prioritization of limited resources. It can be used to investigate questions of historical travel time, capacity limitations, and weather or accident-induced disruptions on waterborne cargo flows. AIS is mandated for nearly all commercial vessels operating in U.S. waters, ensuring robust coverage and tremendous potential to fill longstanding knowledge gaps.
Tools/capabilities are shared to benefit the U.S. Coast Guard, National Oceanic and Atmospheric Administration, U.S. Department of Transportation, U.S. Environmental Protection Agency, Bureau of Ocean Energy Management and U.S. Department of Energy.
NAV
FRM
ENV
PROBLEM
USACE lock operators had limited situational awareness of the vessels using lock infrastructure, resulting in delays to vessel transit and inefficient maintenance planning. Vessel operators were experiencing hazardous and rapidly changing waterway conditions, such as water levels, currents and channel configuration, resulting in groundings at low water or traffic congestion near construction operations.
SOLUTION
LOMA AIS transceivers at lock sites collect vessel location information and present it to lock operators in a user interface that allows them to “see� vessels approaching their locks and plan operations and maintenance accordingly. For vessel operators, the transceivers send up-to-date information for display on onboard navigation systems, alerting operators to real-time water levels, locations of aids to navigation marking channels, lock queue and other information.
IMPACT
Lock operators are no longer caught unaware by vessels arriving at their locks. Lock transits go more smoothly and maintenance has minimal impact on operations. LOMA sends up-to-date information to vessels for display on their onboard navigation systems, alerting them to realtime water levels, locations of aids to navigation marking channels, lock queue and other information. LOMA provides USACE and the Coast Guard an additional tool to disseminate time-critical navigation information to vessel operators when and where they need it.
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LOCK OPERATIONS MANAGEMENT APPLICATION
Information exchange between vessels and shore-side entities is critical to safe, efficient and reliable waterway operations. Automatic Identification System (AIS) equipment aboard vessels and ashore exchanges navigational information autonomously between other vessels and shore-side authorities. The Lock Operations Management Application (LOMA) uses AIS to receive and transmit information, including weather conditions, lock conditions and more. LOMA augments existing data collection systems, easing data collection burdens and facilitating more accurate and timely information for USACE lock operators and managers, vessel pilots, other government agencies, and the navigation industry. ERDC researchers developed a web-based, lock-operator, geospatial display to show LOMA information and to provide interface with other systems. USACE also developed capabilities to assist lock operators with safe operation of the lock and provision of information to nearby vessels automatically and manually. Using LOMA, lock operators have increased situational awareness and are better able to manage and plan lock activities to minimally impact river navigation. USACE program and project managers have better awareness of the river system, and vessel operators and owners are able to better manage vessel movement to minimize delays, saving them time and money. NAV
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NOVEL MATERIALS FOR INFRASTRUCTURE
A popular baseball movie quote declares, “If you build it, they will come,� and ERDC scientists and engineers have created novel structural materials that make building and repairing Civil Works infrastructure faster, better and cheaper. Novel materials such as ultra-high performance concrete and rapid repair cements, metallic materials with improved strength and corrosion resistance, and advanced polymeric materials and composites with improved mechanical properties and durability represent a new selection paradigm that can greatly improve performance at reduced costs. Benefits range from enabling innovative ways to construct and repair to improved durability and strength. Implementation of developed novel materials is providing new capabilities to extend the life of existing USACE aging infrastructure and ensuring that future infrastructure is longer lasting and more resilient to serve the needs of the Nation. ERDC is continuing to develop and transition novel materials for Civil Works applications, across USACE. This R&D research leverages R&D investments in novel materials for military applications to solve maintenance, repair and operational needs of our nation’s aging infrastructure. New technologies developed by industry and academia are being transitioned into ERDC research. This integrated approach ensures that the best solutions are being brought to bear on the challenges facing USACE infrastructure.
NAV
FRM
ENV
PROBLEM
As USACE Civil Works infrastructure surpasses its originally designed service life, material deterioration (concrete, steel, timber) is an increasing concern. Some facilities, dating to the late 1800s, require frequent repair for acceptable performance. Most construction today is based on traditional materials; construction industry and code agencies are reluctant to adopt new materials without successful long-term track records. Stakeholders need solutions to repair/sustain infrastructure over incurring costly new construction and environmental concerns.
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7
PROJECT DEMOS
ACROSS THE CORPS
SOLUTION
Innovative high-strength corrosion resistant steels, composite materials, and advanced cement-based products optimize structures and improve durability in extreme environments. New concrete developments using local materials and chemical admixtures aid in construction processes, reduce costs and provide extended service life. Fiber-reinforced polymer composites are being tested on structural components, large structures, concrete reinforcement, water control structures, piping/penstocks, bridge decks and utility poles.
$3 SAVINGS IN INITIAL REPAIRS
MILLION
IMPACT
ERDC expertise aids in selecting best match, modern day structural materials, and design development and procurement specifications for Civil Works projects. Multiple demonstrations and fielded systems are being used for bridge and lock repair, and as retrofit applications across multiple Corps districts. The systems show reductions in life cycle operational/maintenance costs. FRP composites reduce construction time and maintenance activities.
$50
SAVINGS OVER LIFE MILLION OF REPAIR
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STRUCTURAL HEALTH MONITORING Structural Health Monitoring makes accurate condition assessments about the current and future ability of an asset or system of assets, particularly infrastructure, to perform intended design functions based on sensor and inspection data, numerical models and statistical analyses. Numerous sensing techniques and non-destructive testing methods can be incorporated during construction, rehabilitation or during the operational phase of an infrastructure project. Traditional construction projects do not use structural sensors for construction-phase activities or lifecycle monitoring. New construction offers the opportunity to design a sensing system that can be embedded or protected in the long-term, (design-for-sensing) and offer lower lifecycle costs for monitoring and damage information. Targeted sensor suites can be installed on existing or new assets to detect signals that will indicate damage or assist during construction activities. Various sensors and measurement methods exist for observing information about concrete, steel and geotechnical structures.
NAV
FRM
ENV
PROBLEM
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The complex infrastructure projects the Corps constructs, operates and maintains require capabilities to continuously monitor during operations including when subjected to various hazards to ensure optimal project performance. Knowledge of performance degradation due to aging and use is also needed to inform systems-based asset management approaches that prioritize O&M investments. Past structural health monitoring systems have been costly and challenging.
SOLUTION
ERDC research is developing new approaches that utilize industry technologies implemented to meet unique challenges of Corps projects. These approaches combine traditional sensor-based SHM systems such as SMART Gate with information obtained by unmanned aerial systems and human inspectors. SHM measurements are used in a data analytics approach integrated into the Lock Operation Management Application to provide real-time early warning to operations personnel on project performance concerns.
IMPACT
SHM technologies provide improved project performance and prevent catastrophic failures. The SMART Gate used at Portland District’s The Dalles Lock and Dam provided early indication of miter gate degradation due to fatigue cracking. This allowed rapid proactive response that kept the lock gates from collapsing and the shut down of the entire Columbia River navigation system. Broader SHM implementation is reducing flood risk.
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PROBLEM
Reducing internal erosion and liquefaction without the need for excavation and soil replacement present challenges in earthen structure construction. Currently, the most cost-effective construction uses locally-sourced soil, whether soil is immediately available or obtained from local borrow pits. While time and money make this soil critical, these materials lack the desired performance qualities required to meet project needs. These projects require both rapid soil strengthening and improvement to better ensure the durability and stability of the structure.
SOLUTION
ERDC’s innovative techniques keep costs low while accelerating project timelines to meet emergency infrastructure needs. These include biological soil amendments to rapidly alter and improve soil; biopolymers for rapid re-vegetation; microbiallyinduced mineral precipitation to reduce internal erosion and liquefaction without excavation or soil replacement; in situ biological soil modification to enhance soil without destroying existing, above-ground structures; and adding bacterial inoculants and energy sources to enhance soil communities.
IMPACT
Using natural products for optimizing soil properties, ERDC has improved soil durability and stability, improvising various applications to meet infrastructure needs. Reducing slope instability, altering soil properties and reducing internal erosion and soil liquefaction through biopolymer use translate into millions of dollars in savings for Corps earthen-structure rehabilitation and construction projects. These methods represent the next generation of high-performance, low-cost infrastructure construction and rehabilitation.
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SOIL STABILIZATIONBIOPOLYMER TECHNOLOGY
Using natural products to optimize soil properties for earthen structure construction dramatically improves the infrastructure durability and stability. The use of locallysourced soil is critical to constructing earthen structures such as levees but the materials lack performance qualities required to meet project needs. Research shows that microbially produced polymers and minerals greatly enhance the performance and service lifetimes of earthen structures. ERDC has developed techniques for rapid soil improvement and strengthening that meet these project needs. The most cost-effective construction of earthen structures such as levees is by using locally-sourced soils. Soil amendments, such as lime and gypsum, are extremely effective for improving this soil. Additional improvements can be made using biologically-produced materials such as biopolymers for rapid re-vegetation, reducing slope instability, and altering soil properties to reduce internal erosion and soil liquefaction.
NAV
FRM
ENV
PROBLEM
Backward erosion piping (BEP) has been the cause of numerous dam and levee failures. It remains one of the primary threats to the integrity of our levees today. Inadequate knowledge of the physics and processes, such as seepage and piping mechanics, of sand boil development limited the Corp’s ability to more holistically assess risk and predict potential levee failure during flood events.
SOLUTION
Ongoing ERDC research has focused on developing methods to predict the probability of piping failures and developing faster, more efficient tools to mitigate piping during flood fights. Sand boil monitoring and alert kits deployed during flood events indicate backward erosion and patented, lightweight filters installed in sand boils visually mark boil locations and prevent further erosion. Using these kits and filters also improves knowledge of sand boil hydraulics.
IMPACT
The ERDC-developed approach for assessing BEP has been incorporated into the USACE dam and levee safety risk assessment process, creating a consistent approach for determining failure probabilities. Also, once deployed, sand boil filters could reduce flood fighting costs by $5M to $10M over the next 10 years. If filters permit a faster response time, thereby preventing failure, savings could be more than $100M.
FLOOD FIGHT COST REDUCTIONS
$5MTO$10M OVER 10 YEARS
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SAND BOIL MITIGATION
USACE is the nation’s premier builder of levees and other flood damage reduction structures. One of the first signs that a levee or dam might fail is the emergence of sand boils, which start when floodwater seeps underneath or through a levee, causing the sand at the bottom to “boil” up. ERDC conducted research to better identify and respond to potential levee failures. Research included a study of areas with known sand boil and seepage problems to identify contributing factors affecting levee performance. By documenting histories of sand boils that have occurred during flood events and a better understanding of the different variables and foundation conditions involved, as well as the relationship between sand boil locations and current levee design standards. Other areas of USACE sand boil research include using geophysics and several other methods such as light detection and ranging, cone penetration tests, soil trenching, groundwater geochemistry, mapping with unmanned aerial systems to understand what leads to sand boils and ultimately structural failure.
NAV
FRM
ENV
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ENGINEERING WITH NATURE FOR COASTAL WETLANDS
The USACE Engineering With Nature® (EWN®) initiative is fueling a new vision and approach for developing water infrastructure, wherein natural and engineering processes are aligned to efficiently and sustainably deliver economic, environmental and social benefits (www.engineeringwithnature.org). The collaborative approach laid out in the EWN® Strategic Plan (2018-2023) is deepening partnerships, expanding capabilities, and fielding applications in order to deliver, demonstrate and document this innovative approach to infrastructure development. New science and engineering is being developed, demonstrated and applied to: • Produce efficient, sustainable infrastructure systems • Make use of natural processes to produce added benefit • Expand and diversify the value provided by infrastructure, to include an array of economic, environmental and social benefits • Accelerate project delivery and expanded value through collaboration and partnering New technologies and more than 10 demonstration projects are under way on the U.S. East, Gulf, and West Coasts and Great Lakes.
NAV
FRM
ENV
PROBLEM
Urban, inland and coastal infrastructure is being challenged by increasing range and intensity of flooding threats, resulting in hundreds of billions of dollars in economic damages worldwide. Increasing the sustainability and life-cycle performance of these infrastructure systems presents technical challenges but also tangible opportunities to expand the value provided by infrastructure to include a diversity of economic, environmental and social benefits.
SOLUTION
Natural and Nature-Based Features (NNBF) such as wetlands, islands and reefs provide engineering benefits to directly support flood risk management, and other economic, environmental and social benefits. NNBF, used in combination with conventional infrastructure (levees, flood walls, etc.) is a powerful way to develop resilient infrastructure systems. New science and engineering are being developed, demonstrated and applied across the U.S. and internationally.
IMPACT
Wetlands provide flood risk and damage reduction, habitat supporting fisheries and wildlife, water and sediment quality, recreation and other benefits that provide economic and non-economic value. The Llloyds Tercentenary Research Foundation used industry engineering tools to estimate the flood engineering value of coastal wetlands during Hurricane Sandy. Analysis showed existing wetlands provided $625M of engineering value in avoided flood damages. These and other project results are being translated into international guidance for designing future infrastructure systems.
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HARNESS THE POWER OF ERDC AT
ERDCINFO@USACE.ARMY.MIL PUBLISH DATE: MARCH 2019 APPROVED FOR PUBLIC RELEASE DISTRIBUTION UNLIMITED AUTHORED BY: ERDC CORPORATE COMMUNICATIONS OFFICE ERDC CIVIL WORKS R&D TEAM DESIGNED BY: ERDC INFORMATION TECHNOLOGY LABORATORY COVER PHOTO: MARTY KITTRELL
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