Ice Center

The 72,000 square feet Dakotah! Ice Center was designed with state of the art energy efficiency and environmentally friendly components. In addition to a 32,000 square foot green roof, sixteen solar panels, rain gardens, and recycled benches, the ice center features 14,000 square feet of VAST Permeable Composite Pavers installed along the parking lot center aisle and at the entrance of the facility.

One reason the SMSC chose the VAST paver over more traditional concrete or clay paver is because the VAST paver is made from 95% recycled tire rubber and plastics. Additional benefits of using VAST pavers:

1. Every 1,000 square feet of VAST Composite Pavers saves 500 scrap tires and 15,000 plastic bottles from landfills.
2. Manufactured with zero toxic or harmful emissions and zero waste
3. 100% of all VAST Composite Pavers can be removed and recycled into new pavers
4. LEED credits
5. Light weight, durable, maintenance free
6. Reduced installation labor costs

Employee Parking Lot

Project Photo Gallery

The purpose of this project was to reduce hydromodification and water quality impacts from polluted runoff by reducing impervious surface coverage and treating runoff using bioretention. This project entailed the construction of two bioretention areas, a pervious paver patio, and pervious asphalt.

The project is located on the Reservation lands of the Shakopee Mdewakanton Sioux Community (SMSC). The SMSC is located in Scott County, approximately 25 miles southwest of Minneapolis, Minnesota. The major watershed, as identified by the United States Geological Survey, is located in Hydrologic Unit Code 07020012.

The watershed for this site is approximately 2.6 acres. Prior to the project the entire site was comprised of impervious asphalt and metal rooftops. Asphalt, concrete, brick, stone, and metals seal surfaces, repel water, and prevent precipitation and melt water from infiltrating soils. Research studies have shown that water quality decreases when the amount of impervious surface increases. This is due to the increased runoff and the high levels of pollutants associated with impervious surfaces. The effect is an alteration of the plant and wildlife communities and a general decrease in biodiversity.

Before this project the rooftops, asphalt, and sidewalks drained to Wetland C-1L without treatment. Water sampling by the SMSC Land and Natural Resources Department found impacts from excessive runoff, oil, and grease and elevated levels of deicing salts and metals from automobiles.

This project removed 1.7 acres of impervious surface and replaced it with features to improve water quality and allow the water to enter the wetland at a slower rate. The project goals were:

• Improve runoff water quality
• Reduce hydromodification
• Improve awareness of alternative runoff treatment methodologies

In order to accomplish these goals impervious asphalt was removed and replaced with two bioretention areas, a pervious asphalt section, and a pervious paver patio. Since only a portion of the lot (17,000 ft²) was replaced with pervious asphalt, a bioretention areas was constructed to treat a large portion of the remaining area. Additionally, a bioretention area was constructed to treat roof runoff, and a pervious paver patio was built to handle overland runoff from the new landscaped areas.

Modeling completed prior to the project showed that runoff will decrease and water quality will be improved. Research indicates that little if any deicing other than plowing is needed for pervious pavement, so a reduction in chlorides should also be realized.

Rain Gardens | Pervious or Porous Pavement

Project Issues
The primary issue with building a pervious area is preventing potential contaminant from entering the drainage layer or the pervious asphalt. This is especially problematic during construction but can also be an issue post-construction.

During Construction
This problem was solved by working closely with the engineers and maintaining constant communication with the contractor. Two preconstruction meetings were held; one with the engineers and one with the contractor and engineers. It was conveyed that soil or mulch was not to be carried over the pervious asphalt and the bioretention areas needed to be protected from silt. This was a difficult proposition because the pervious asphalt surrounded the landscaped areas and the order of operations was usually to complete the landscaping last. After some discussion it was determined that the contractor would work with the Land Department staff to construct from the building outward. While this did provide some inconveniences, this did accomplish the goal of keeping the pervious section free from contaminants.

Post Construction
To minimize the contaminants entering the pervious asphalt, drainage to the lot from external sources was minimized. This was done by capturing most of the runoff before it enters pervious asphalt. Most of the site drains to a pervious paver patio or a bioretention area. The entire site, with the exception of asphalt, was planted and covered with mulch or seeded with buffalo grass and covered with erosion control blanket. All open soil was covered and any other project debris was removed from the site.

Collaborators
Shakopee Mdewakanton Sioux Community
United States Environmental Protection Agency

Contractor | Hentges, Inc.

Subcontractors | Black Diamond Landscaping, Keller Fencing, Choice Electrical

East Bioretention Area | Pervious Asphalt | Pervious Paver Patio | Rock Drainage

Resources
Bioretention Detail
Bioretention Grading Detail
Lot Construction Detail
Pervious Detail
Pervious Project Bid Document
Staging Detail

Videos
Articulated Concrete and East Side Bioretention
Installation and Rolling of Pervious Asphalt
Landscaping and Pervious Patio
Pervious Asphalt Water Application
Roof Runoff Treatment Using Bioretention

Links to Low Impact Development Sites
http://www.lowimpactdevelopment.org/
http://www.epa.gov/nps/lid/
http://www.lid-stormwater.net/background.htm
http://www.duluthstreams.org/stormwater/toolkit/paving.html

In 2006, the Shakopee Mdewakanton Sioux Community (SMSC) constructed the largest green roof in the upper Midwest at its new Water Reclamation Facility. The 30,200 square-foot green roof contains more than 45,000 plants, including native prairie grasses and flowers. The green roof system disperses significant amounts of water back into the atmosphere through evaporation and transpiration. During dry spells, the plant life on the roof can be supported using reclaimed wastewater from the treatment process itself, yet another benefit of the high level of treatment the facility provides.

Click on the layers in the image below to learn more about the construction details of this green roof.

Research

The Shakopee Mdewakanton Sioux Community recognize the research opportunity presented by the Water Reclamation Facility (WRF) green roof and its ability to answer some of the unanswered questions for Midwest green roofs. Five research projects are currently being conducted (started in 2007):

• Looking at building heating and cooling on and inside the WRF and an adjacent building without a green roof.
• Determine plant and irrigation influence on soil moisture to optimize water retention.
• Examine influence of irrigation amount on percent cover of roof over two growing seasons.
• Establishment of Sedum by seeds, cutting, or plugs and various irrigation levels to determine optimization of upfront cost and final “green” cover.
• Competition of Sedum and native prairie vegetation under irrigation conditions past establishment.
• Explore pollinator usage of native prairie plants used in the green roof vegetation.
  

Plants

A mixture of plants native to Minnesota and traditional green roof vegetation (stonecrop) were planted on the roof in summer 2006. By the end of the first full growing season in 2007, the green roof had achieved 60% vegetative cover. Stonecrop makes up the majority of the understory, while the native grasses and forbs make up the mid- and upper- canopy. The vegetation receives water from rainfall and an irrigation system. Water from the irrigation system is the treated discharge from the WRF.

Stonecrop, native grasses, and some native forbs did very well in the first growing season. Both stonecrop and native forbs were utilized by local pollinators. In addition to planted species, the green roof also hosts several kinds of volunteer plants. These surprisingly include wetland species like cattail, willow, and cottonwood.

Temperature Study

One of the benefits often attributed to green roofs is temperature regulation. Green roof advocates claim that shade and evapotranspiration produced by the vegetation will keep roof temperatures lower; this in turn will reduce the need for cooling during periods of warm weather. Additionally, these same processes will aid in mitigating the urban heat island effect which exists in developed areas.

One of our ongoing research projects will address these potential benefits. We are currently recording air temperatures at five different heights to create a temperature profile from a height of one meter above the green roof to 1.5 meters above the floor directly below the green roof. A similar profile is being monitored in another area of the building that has a typical membrane roof with no vegetative cover. A comparison of these data sets will show whether there is a significant difference in air temperature above a green roof and whether any temperature differences are translated to the interior of the building.

Soil Moisture Study

Traditional roofs are designed to respond quickly to precipitation events and efficiently move water off of the structure. This water typically ends up in a storm drain. During a storm event this process can lead to flash flooding and erosion. With a green roof the opposite is true. One of the advantages of a green roof is its ability to retain water which can be taken up by plants and transpired back into the atmosphere or slowly released through the drainage system.

We are currently gathering soil moisture and precipitation data on a small section of our green roof. This data will allow us to quantify the response of green roof soils not only to precipitation events, but also to periods of dry weather.

A Rain Garden is a garden that is designed specifically to collect and infiltrate rainwater that falls on nearby impervious surfaces. Downspouts from rooftops are directed to the rain garden, and swales direct water from impervious surfaces like sidewalks and driveways.

The benefits of Rain Gardens are:

• Rain Gardens reduce storm water runoff which:
• Reduces the amount of pollutants such as sediment, nutrients, and metals that enter lakes, streams, wetlands, and rivers
• Rain Gardens are beautiful
• Rain Gardens attract Butterflies and Birds
• Rain Gardens are low maintenance once established

For more information on Rain Gardens, including manuals to construct one in your yard, see the links below. Click here to view the Rain Garden Brochure (pdf).

Links

University of Wisconsin – Rain Garden Manual
www.clean-water.uwex.edu/pubs/pdf/home.gardens.pdf

Minnesota Pollution Control Agency – Rain Garden Manual
www.pca.state.mn.us/publications/manuals/stormwaterplants.html

Applied Ecology – Rain Garden Manual
www.appliedeco.com/RainGarden.cfm

Minnesota DNR list of Native Plant Suppliers and Landscapers by Region
www.dnr.state.mn.us/gardens/nativeplants/suppliers.html

Minnesota Conservation Volunteer Rain Garden Article
www.dnr.state.mn.us/volunteer/mayjun04/raingardens.html

Big Eagles Rain Garden Photo Gallery I Mystic Rain Garden Photo Gallery

The project scope entailed installing three bioretention areas and a hydrodynamic treatment structure. Two separate sites were chosen, Big Eagles Village and Mystic Lake Boulevard. Two bioretention areas and a hydrodynamic device were installed in Big Eagles Village. The second bioretention area was installed adjacent to Mystic Lake Boulevard south of Mystic Lake Casino.

Location
The Shakopee Mdewakanton Sioux Community (SMSC) is located in Scott County, approximately 25 miles southwest of Minneapolis, MN. The major watershed, as identified by the United States Geologic Survey, is Hydrologic Unit Code 07020012. The SMSC owns land in Minnesota Department of Natural Department of Natural Resources designated minor watersheds 33131 and 33122.

Project Need
Urban runoff water from buildings, streets and sidewalks, lawns and construction sites carry many pollutants including: sediment, nutrients, bacteria, oil, metals, chemicals, road salt, pet droppings and litter (modified from www.protectingwater.com/urban.html). Changes in the hydroperiod due to impervious surface can change vegetation characteristics and reduce species diversity to the exclusion of sensitive organisms.

Several Reservation water bodies are identified as degraded in current and previous nonpoint pollution assessment reports. The primary pollutants of concern are sediment from streets, metals and nutrients from vehicular traffic, nutrients from residential landscaped areas, salts from deicing operations, and rooftop runoff. In addition, it is suspected that a loss of vegetation and wildlife diversity can be partially attributed to hydromodification.

Project Goals
This project specifically addressed an urban non-point pollution issue, polluted impervious surface runoff. Furthermore, the project established a precedent on Casino grounds and provided a basis for solving key urban development issues using alternative treatment methods. The funding from the EPA was used to retrofit an urban and commercial site by installing a hydrodynamic device and three bioretention areas. This was done in order to treat polluted urban runoff containing sediment, excess nutrients and metals, and provide rate and quantity control before the runoff impacts jurisdictionally shared wetlands, lakes and streams.

Three specific project goals were developed:

1. Improve runoff water quality before it enters Wetland S-1a, Mystic Lake, and Wetland S-17b (Meadows Golf Irrigation Pond),
2. Reduce hydromodification impacts to Wetland S-1a, and
3. Improve awareness of alternative runoff treatment methodologies by constructing a bioretention area in two highly visible sites.

In order to accomplish these goals eight acres within Big Eagles Village was redirected to the Hydrodynamic Structure (Downstream Defender) and rain gardens. Storm sewer was rerouted and curb was cut to treat the newly directed impervious surface runoff. The rain gardens provide both water quality treatment and runoff rate reduction. The hydrodynamic structure captures sediment providing additional water quality treatment. The Mystic Lake Boulevard rain garden, while small in scale, is in a high visibility area showing that aesthetically pleasing water quality treatment devices are possible.

Expected Results
In the short term it is expected that water quality will be improved with the installation of the bioretention area and hydrodynamic device in Big Eagles Village. If successful, the installation of the bioretention area near Mystic Lake could spur small-scale treatment in other locations near the casino. A change in mindset from the traditional way of thinking about runoff could result in additional rain gardens planted and improved water quality over the long term.