Our mission is to protect, manage and improve the water resources of the Capitol Region Watershed District.
INSIDE
2 Trillium Nature Sanctuary takes shape 3 William Street Pond BACK Stop the Rain Drain 2011 Capitol Region Watershed District Winter 2012
Green infrastructure in the Central Corridor by Anna Eleria
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he construction of the Central Corridor Light Rail Transit (CCLRT) project is a unique opportunity to improve stormwater quality in a major urban transportation corridor. The Metropolitan Council, Capitol Region Watershed District (CRWD), the City of Saint Paul and Ramsey County are funding and constructing green infrastructure (see definition box) practices to mitigate stormwater pollution. Additional funding for the project comes from a State of Minnesota Clean Water Fund grant.
Green infrastructure is a stormwater management approach that uses natural landscape features and hydrologic processes to treat stormwater by infiltrating, evapotranspiring, and/or reusing runoff. Green infrastructure also achieves other environmental goals such as carbon sequestration, reductions in urban heat island effect, improved air quality, improved wildlife habitat and increased opportunities for outdoor recreation.
The two-way commuter rail system will connect the downtowns of Minneapolis and Saint Paul in an urban corridor that is home to both commercial and industrial land uses and residential property. The current drainage system within the project limits sends untreated stormwater from about 111 acres of impervious surface directly to the Mississippi River. Portions of this stretch of the river are impaired for turbidity, nutrients and bacteria.
Based on its large project area, the 100+ acre CCLRT construction area is required to meet CRWD Watershed Rules. CRWD Rules require stormwater quality improvements by retaining one-inch rainfalls through best management practices (BMPs) that remove 90% of sediment and 60% of phosphorus. Four types of green infrastructure practices have been selected for the Corridor: • integrated tree trench system; • stormwater planters; • rain gardens; and • infiltration trenches. The integrated tree trench system is being constructed on both sidewalks along 5.2 miles of University Avenue where well-drained soils exist. The system will receive University Avenue stormwater runoff 1) via catch basins CCLRT continued on page 3
Aldine Street stormwater planter
Capitol Region Watershed District 1410 Energy Park Drive, Suite 4 • St. Paul, MN 55108 • 651-644-8888 • www.capitolregionwd.org
Established in 1998, the Capitol Region Watershed District covers 40
Board of Managers: Robert P. Piram, President; Joe Collins; Mary Texer; Mike Thienes; Seitu Jones Staff: Mark Doneux, Administrator Melissa Baker, Water Resource Technician Elizabeth Beckman, Education & Outreach Coordinator Joy Degl’innocenti, Seasonal Water Resource Technician Anna Eleria, Water Resource Specialist Bob Fossum, Water Resource Project Manager Morgan Greenfield, Seasonal Water Resource Technician Liz Hutter, Administrative Assistant Forrest Kelley, Permit Coordinator Matt Loyas, Water Resource Technician Dawn Nelson, Office Manager Britta Suppes, Water Resource Technician
square miles and includes portions of the cities of Falcon Heights, Lauderdale, Maplewood, Roseville and St. Paul. Located within Ramsey County, it has a population of 245,000 people. The district drains to The Mississippi River, also its primary water resource. Como Lake, Crosby Lake, Loeb Lake and Lake McCarrons are also located in the District.
Capitol Region Watershed District 1410 Energy Park Drive, Suite 4 St. Paul, MN 55108 • 651-644-8888 • www.capitolregionwd.org
Trillium Nature Sanctuary takes shape by Elizabeth Beckman
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he vision for a nature preserve in the heart of Saint Paul is moving forward. The Trillium Nature Sanctuary, a 40-acre site near I-35E and Cayuga Avenue, is part of a larger plan for the Trout Brook Regional Trail corridor. The new section of the trail will extend from Jackson Street to connect to the Gateway Trail (see box below) at Cayuga Avenue. In the 1880s, Trout Brook ran from Roseville’s Lake McCarrons to the Mississippi River. The residential area to the west of Trillium was perched on a bluff overlooking Trout Brook valley. With the development of the railroad industry, the creek was filled and Trout Brook was diverted into a storm sewer pipe. This permanently altered the natural valley as well as the
neighborhood’s connection to the natural environment. To help restore this relationship, a portion of Trout Brook will be recovered through daylighting, a process by which a stream previously diverted underground is unearthed to an above ground channel. Wetlands and ponds will also be created at this current brownfield site using a system that intercepts stormwater runoff from the neighborhood (see figure). Since CRWD’s current Watershed Plan prioritizes Stream Corridor Restoration and Wetland Restoration, CRWD has worked in partnership with the City of Saint Paul to design a stream channel, wetlands and ponds. Construction of these elements of the Sanctuary will begin in 2012.
Figure: Trillium Concept Plan
Gateway State Trail Located on a converted railbed, the Gateway State Trail features 18 miles of paved trail for hiking, biking and skating. Capitol Region Watershed District The trail begins in the city of St. Paul and ends at Pine Point Regional Park north of Stillwater. The Gateway Trail is generally level and wheelchair accessible. More information at Minnesota DNR Trails: www.dnr.state.mn.us/state_trails/index.htm
2 Capitol Region Watershed District Winter 2012
William Street Pond by Forrest Kelley
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illiam Street Pond is a stormwater collection pond near William and Elmer Streets in Roseville. To improve the pond’s ability to remove sediment and phosphorus from stormwater flowing through it on the way to Lake McCarrons, pond improvements were completed in September 2011: • contaminated sediment was removed from the pond to restore its full storage capacity • a new baffle device (see box, right) and pond inlet pipe were installed • two iron-enhanced sand filtration benches (see photo, right) were added to the slopes near the pond outlet
Iron filings are within in the sand bench just above the line of rock, also known as rip rap.
Iron-enhanced sand filtration helps remove excess phosphorus from stormwater flowing through. The benches are flat areas next to the water line about five feet wide and two feet deep. These benches were filled with a mixture of sand and iron filings. When stormwater flows through the sand, dissolved phosphorus pollution chemically bonds to the iron which prevents it from entering Lake McCarrons. Contractors encountered difficulties during the project: when it rained five inches in one hour on July 16 a sump was overloaded and the baffle dislodged. Also, groundwater seeps made the sediment very mucky and difficult to dry after it was dredged from the pond. More dredge material was present than expected -- some 600 cubic yards -- and local landfills would not accept it because of its high water content. As a result, the sediment was hauled to Glencoe, MN at an increased cost. Thanks to project partners Ramsey Conservation District and city of Roseville, the improved William Street Pond will remove an additional 7 pounds of phosphorus per year from stormwater resulting in less algae growth in Lake McCarrons.
What’s a SAFL Baffle?? Developed at the University of Minnesota St. Anthony Falls Laboratory (SAFL), the “SAFL Baffle” is a device that reduces sediments in stormwater from reaching Minnesota lakes and streams. The “Baffle” is installed in a sump—a vertical cylinder that connects sewer pipes. The baffle slows down water rushing into the sump and prevents it from picking up sediment that has settled there during previous rain events.
CCLRT continued from page 1
runoff to infiltration trenches and 2) from sidewalks via pervious pavers that direct runoff to structured soils that support the health of boulevard trees. The system will in turn improve air quality, reduce the urban heat island effect and enhance the aesthetics of the corridor. As of December 1, nearly 40% of the tree trench is complete. Eleven additional green infrastructure projects are being constructed on streets connecting to University Avenue. In fall
2011, three stormwater planters were constructed at the following intersections with University Avenue: Aldine Street SE, Albert Street NW and Albert Street NE. One rain garden was constructed at Pillsbury Avenue NW, and the City of Saint Paul has also constructed two infiltration trenches at St. Albans Street South and Arundel Street South. Other BMPs to be built in 2012 include:
Rain Gardens Syndicate Street Southwest Marion Street Southwest Marion Street Southeast Stormwater Planters Griggs Street Northwest Oxford Street Southeast CCLRT green infrastructure practices are expected to remove 83 pounds of phosphorus and two tons of sediment per year from stormwater runoff which will improve water river quality.
Winter 2012 Capitol Region Watershed District
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1410 Energy Park Drive, Suite 4 St. Paul, MN 55108 651-644-8888 651-644-8894 fax www.capitolregionwd.org
Stop the Rain Drain 2011 Stop the Rain Drain teaches residents about reducing runoff and helps them take action.
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his year, Minnesota GreenCorps (a program of AmeriCorps) staff Kat McCarthy traveled the alleys and sidewalks of CRWD in search of guttered garages whose roof drainage could be safely directed to lawn or garden areas – she found 450! Our professional contractors at DTD Construction and LetUs Services completed redirection work for 69 of the 450 homeowners who wanted CRWD’s help, and 325,000 gallons of runoff were redirected in 2011.
No gutters? No problem! This roof drains to a flower garden that intercepts nearly all the runoff.
Why Stop the Rain Drain? Because when it rains, it drains! Rainwater from our roofs and gutters drains to local lakes and the Mississippi River via storm drains, picking up pollution along the way: leaves, grass clippings, auto fluids, trash and pet waste all harm our local waters. Stay tuned for Stop the Rain Drain 2012!
Learn more at stopraindrain.org
It can be simple to Stop the Rain Drain. This downspout can be easily redirected onto grass nearby.
Nowhere to run to: some downspouts have no lawn or garden nearby. In some of these scenarios, a rain barrel or two can store roof water to be used on nearby gardens.