Background
From 1989 to 2006 the Shakopee Mdewakanton Sioux Community used a sewer system connected to the Metropolitan Council's Blue Lake Treatment Plant in Shakopee which discharges effluent directly into the Minnesota River. During that time the SMSC considered development of its own wastewater treatment or reclamation facility located on Community land. After study and research by staff, a Water Reclamation Facility (WRF) was proposed.

Construction on the facility began in February 2005 and took 18 months to complete on an expedited schedule. Principal designer was Bolton & Menk, Inc., Environmental Services Division, Mankato, Minnesota. Architect Plus of Faribault, Minnesota, designed the building. General contractor was Rice Lake Construction Group, Deerwood, Minnesota.

The SMSC opened the WRF on trust lands on August 18, 2006. The WRF treats wastewater from all tribal residences and Community enterprises, including Mystic Lake Casino Hotel, located south of County Road 42 in Scott County, Minnesota.

"Having our own wastewater reclamation facility increases sovereignty, facilitates future planning, and decreases dependence on other jurisdictions," said SMSC Chairman Stanley R. Crooks.

The unique characteristics of the WRF are the direct result of the Community’s dedication to protecting and preserving the environment.

The Technology
The SMSC Water Reclamation Facility is one of less than a dozen in the United States which utilizes BAF (Biologically Aerated Filtration) technology, a continuous flow process developed in Europe where land is at a premium and water quality standards are very high. In essence, millions of tiny Styrofoam beads provide a home for bacteria which "eat" suspended and dissolved solids in the wastewater.

The wastewater facility provides preliminary treatment through the use of screens and a vortex grit removal system and clarification. The facility also provides secondary treatment (the BAF system), disinfection, and biosolid treatment and disposal. Membrane filtration is the final purification process before ultraviolet disinfection (similar to what is used to purify drinking water) and discharge.

Control of the WRF is by a computer-based system which provides monitoring of all equipment. Redundant systems assure continuation of services. Room for future growth was also built in to the facility. The support facilities for the plant include a standby diesel power generator in the event of a loss of electrical power. An onsite laboratory performs the required testing, assuring proper operation of the facility.

High quality air scrubbers functioning throughout the building minimize odor outside the building. Noise dampening materials and construction processes were also used to keep sound from WRF operations to a minimum outside the building.

Initial Discharge of Effluent
Typically, effluent, clean treated water that flows out of a treatment facility, is discharged to a river or other public body of water. In the case of the SMSC’s facility, the effluent is routed through two wetlands within the Community and then flows into a large irrigation pond. Water from the pond is then used to irrigate The Meadows at Mystic Lake golf course, as well as other areas. On January 22, 2007, the discharge of treated water to the wetlands took place for the first time. The effluent traveled through a pipe to the wetlands west of Dakotah Meadows RV Park and Mini Storage. Rigorous standards for water quality were met before discharge. In warmer months the effluent also travels over a waterfall into the wetland adjacent to the WRF. In the winter it would freeze.

During the irrigation season, very little effluent from the WRF exits SMSC land, eliminating downstream impacts. Water discharged from the facility contains less dissolved solids than the water already present in the wetlands and meets drinking water standards for surface water use.

Wildlife flocked to the site of the effluent release, relishing the warm (57 degree Fahrenheit) water during the cold Minnesota winters when most other water bodies were frozen. Open water all winter in the wetlands provided a home for minnows which were eagerly devoured by water fowl. Even during warm weather the wetlands provide a home for Canadian geese, muskrats, mallards, and others.

Biosolids
Solids remaining after processing, called "biosolids," are pressed and dried for use as fertilizer in a drying process that is the first of its kind in the United States. Influent from SMSC facilities and residents flow into the WRF for treatment. Inorganic solid materials are removed for transfer to a solid waste dump in the initial treatment operations. Organic matter, called biosolids, which remain are pumped to the biosolid room for treatment. A polymer, or coagulant, is then added to help de-water the materials.

Next, equipment removes the water from the sludge in two processes. The first is a belt press, and the second is a large oven, nicknamed the “Easy Bake.” The drying process, which takes 30-32 hours, also sterilizes the biosolids, which are then placed into large bags for storage and transport. The drying process converts the biosolids to a solid product with a water content less than 8%. The SMSC uses these biosolids on The Meadows at Mystic Lake golf course and other agricultural lands within the Community. The biosolids are also mixed with mulch and used on flower beds and landscaping throughout the Community. It may also provide a future fuel source in waste-to-energy recovery facilities such as the Koda Energy project which will be operational in December 2008.

WRF Honored for Excellence
The Shakopee Mdewakanton Sioux Community Water Reclamation Facility has been honored by three organizations for its excellence. The Minnesota American Council on Engineering Companies (ACEC) presented the SMSC with a Grand Award at a banquet held January 26, 2007. The SMSC project won one of nine Grand Awards for the best overall engineering achievement. The ACEC competition recognizes projects that demonstrate a high degree of achievement, value, and ingenuity. For more than 40 years, this competition has awarded uniqueness and originality; future value to the engineering profession and perception by the public; social, economic, and sustainable development considerations; complexity; and successful fulfillment of client/owner’s needs, including schedule and budget.

The Minnesota Society of Professional Engineers (MSPE) 2007 Seven Wonders of Engineering Award was presented to the SMSC February 23, 2007, at the Hotel Sofitel in Bloomington, Minnesota, as part of MSPE’s Engineers Week celebration. Entries were judged on the engineering methods, systems, and skills utilized by the project team; the project’s advancement of the engineering profession; the complexity of the project and how the project team overcame this complexity; the significance of the project to society; and the extent to which the entry meets the needs of the market, client, or owner.

The SMSC facility was also awarded the Minnesota Governor’s Award for Excellence in Waste and Pollution Prevention. The 16th annual award was presented during a banquet on February 28, 2007. The award honors superior environmental achievement by Minnesota non-profit organizations, businesses, and private institutions for programs or projects that benefit the environment by reducing or eliminating wastes and pollutants at the source. Award winners selected by the Minnesota Pollution Control Agency for this award are leaders at the highest level of environmental achievement.

Green Roof
The Water Reclamation Facility features a 31,000-square-foot green roof, the largest in the Upper Midwest, which contains more than 45,000 plants which were hand planted as seedlings. Then seeds for native prairie grasses and flowers were strewn to fill in the spaces between plants, creating a lush vegetative roof. 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 is supported using reclaimed wastewater from the treatment process itself, yet another benefit of the high level of treatment the facility provides.

The SMSC Business Council suggested a Green Roof be used on the facility because of the benefits to the environment. A Green Roof reduces the total storm water runoff from the building. It also reduces erosion and improves water quality. The technology also extends the life of the roof to 50 years by protecting it from ultraviolet radiation. It also simplifies temperature management inside the facility, because the green roof lowers the temperature inside the building which reduces energy consumption. Most of the WRF, though not air-conditioned, remains comfortable throughout the year even during the hot months of summer. The building itself, aside from the superior treatment process, is designed to produce the minimum environmental impact on the site and the surrounding area.

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