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Engineering sections: Public Works divisions: Related links: |
Current water resource projects
Recent water resource projects
SE Anderson LakeThe Southeast Anderson Lake Water Quality Improvement Project is using a chemical treatment on Southeast Anderson Lake to address Curly Leaf Pondweed, an invasive species related water quality issues. The Project requires four successive years of herbicide applications to treat the Curly Leaf Pondweed. The first application was performed during the spring of 2009 and the last application is currently scheduled to be performed during the spring of 2012. Following the four years of herbicide treatment, an alum treatment will be applied in 2013 to address internal phosphorus loading. However, if water quality continues to improve and Curly Leaf Pondweed continues to decline, it is possible than an alum treatment may not be necessary. The project is a joint effort between the Nine Mile Creek Watershed District and the City of Bloomington. Water quality measures continued to improve in 2010 relative to water quality measures documented between 1971 and 2001 and 2009. Summer average water quality data are summarized in the table below.
Treatments on SE Anderson are designed to control Curly Leaf Pondweed and suppress the production of turions (seeds). Curly Leaf Pondweed plants can produce up to 900 turions annually and growth of plants from these turions can significantly increase Curly Leaf Pondweed coverage and degrade water quality. Lake-wide turion statistics are summarized below.
Bush Lake outlet - phase II shoreline restorationRestoring the entire shoreline of Bush Lake. Includes chemical spraying of undesirable non-native invasive species and spot planting/seeding where needed. On-going for next 4 years. This constitutes the second phase of the Bush Lake Outlet Project. Last year a pumped outlet into Anderson Lake was constructed at Bush Lake by the Nine Mile Creek Watershed District. Previous to this, no outlet existed for Bush Lake and extended periods of high water often caused increased erosion, damage to property and negatively impacted water quality. Storm sewer color TV inspectionWork includes closed circuit television inspection of storm sewer mainline pipe at locations of future reconstruction and overlay projects. Inspection results are used to determine necessary repairs in conjunction with future roadway projects. Inspection records also provide information to minimize long-term maintenance costs and traffic interruptions, and reduce erosion. Storm sewer maintenanceThe 2011-901 Storm Sewer Maintenance Project includes maintenance, and construction of the storm sewer system at approximately 18 sites in the City. Residents living in the vicinity of these sites will be notified of the pending construction and, if necessary, informational meetings will be held. Activities will be scheduled and coordinated with nearby construction project to minimize conflicts and avoid further traffic delays. Project Locations and Work Description:
Pond maintenance projectSediment removal, bank stabilization and minor storm sewer maintenance are regularly completed during the winter months to provide better access to equipment and crews, minimize risks of problems with rain, and reduce damage to the environment. Final restoration typically begins in the spring and is completed by early summer. Sediment accumulates in lakes and ponds from erosion, winter ice control and other sources. Phosphorus and other nutrients attach to the soil particles and contribute to algae blooms and excess aquatic vegetation. Sediment removal from lakes and ponds connected to the City's storm sewer system provides water quality benefits by reducing nutrients and increasing the normal water volume and storage capacity. Lakes and ponds are excavated to similar size and shape as originally constructed or adopted as storm water retention/detention ponds. Permits are required from the MnDNR, MPCA, watershed districts and other water authorities. The 2011-905 Pond Maintenance Project proposes to excavate accumulated sediment from Wrights Lake (E. 86th St & Old Cedar Ave.) and Countryside West (W. 104th St & Zinran Ave. S.). Construction will take place in January and February 2012, with restoration later in the spring. Please use caution around the ponds during excavation, thin ice, heavy equipment and trucking operations can be dangerous. Spring rains should restore the water levels by early summer. The excavated sediment will be composted, recycled or landfilled as determined by chemical analysis of sediment samples. Sediment contaminated with polycyclic aromatic hydrocarbons (PAHs) must be disposed according to Minnesota Pollution Control Agency guidelines. Use keywords "Driveway Sealcoat" on the City of Bloomington website for more information.
For additional information or questions regarding this project, please contact: Lower Penn Lake Management PlanThe City of Bloomington Engineering Division has been working with the Department of Natural Resources (DNR), Nine Mile Creek Watershed District, and Public to gather information to ultimately develop a management plan for Lower Penn Lake. The goal of the plan is to outline detailed actions to preserve, maintain, or achieve desired attainable uses for the lake. Follow the link below to visit the project web page. Wetland Inventory Update 2010The 2010 Wetland Inventory Update involves updating the City’s wetland resources using current wetland assessment methodology, MnRAM 3.2 (pronounced "minn ram". The assessment results will be used to update the functions and values of the 240 wetlands that are on public lands, public easements and/or part of the City storm sewer system. The existing wetland inventory was done as part of the 1997 Wetland Protection and Management Plan and supplemented in 2000 with the wetlands below the Minnesota River bluff line. The benefits of this inventory for the City and its residents include:
WSB & Associates is the engineering consultant doing the assessment and will be doing the field work in early July thru mid-August, 2010. Field crews will carry identification, wear high-visibility clothing and will use easements and public property to access the ponds and wetlands to the extent practicable. While it is true that most wetlands in Bloomington have been affected by development and changing land uses through the years, the wetlands still perform numerous functions, and have varying degrees of value for each of the functions they provide. The wetland data will be incorporated into the City's GIS database for uses such as reviewing potential development, natural resource management, restoration projects and managing the City's storm sewer system.   Parking lots can be designed with the environment in mind. Harrison Park regional infiltration projectThe City of Bloomington recently constructed an Infiltration Demonstration Project at Harrison Park. The Project consists of a permeable asphalt parking lot and two rainwater gardens. This location was selected for several reasons, including; the deteriorated parking surfacing, proximity to Nine Mile Creek, central location, good infiltration capacity of the existing soils and high public profile. Project Design Objectives:
Construction of the permeable asphalt parking lot and rainwater gardens was completed in early October 2008. The asphalt differs from standard asphalt in that it contains very little fine aggregate that would lead to dense impervious pavement. The pavement looks very coarse, since it has high void content, and is slightly more difficult for construction workers to get a "polished smooth" surface. A preliminary test with a flush truck confirmed that water flowed right thru the pavement. The porous asphalt and crushed granite rock base layers are designed to infiltrate storm water and minimize runoff to nearby Nine Mile Creek, reducing annual runoff by 90%. A monitoring plan is planned to confirm this anticipated performance. How to keep the water flowing thru the pavement? Twice a year the parking lot will be swept by a special vacuum type street sweeper. Keeping sand, grit and other particles from clogging the pours is key to maintaining the infiltration capabilities of the pavement. And when the snow flies, sand and salt are not required for winter maintenance, just plow the snow off as usual, and solar energy will melt the remaining snow right into the porous pavement. Two rainwater water gardens were also constructed to demonstrate alternative methods of treating storm water. One rainwater garden will be in the center parking median, containing native trees and plants that can tolerate drier conditions, as this area will not get much runoff. The other rainwater garden will be located west of the access to Nine Mile Creek. This rainwater garden is designed to capture runoff from the adjacent trail, apartment parking lot and the park area, and is designed with native flowers, grasses and shrubs that can tolerate more frequent wet conditions. These garden areas will require little maintenance after the establishment period, and offer natural beauty and infiltration of storm water runoff. The project was designed by the Engineering and Park Maintenance Divisions of Public Works. Public Works staff has been monitoring and maintaining the parking lot for one year. We are seeing continued infiltration and good performance. Several areas of concern: snow plows have scraped some surface rocks, flow from the standard asphalt may be carrying extra fines and overloading the pervious pavement causing some plugging, and the rainwater garden shared with the Woodland Apartments is undersized (but that was all the space available). Engineering staff will continue to monitor the parking lot performance for the coming years. The following resources are available for download. We respectfully request that any use other than personal should include credit to the City of Bloomington.
Invasive species buffer managementIn July, 2006, the City hired a consulting company to manage invasive species in the native buffers around Lower Penn Lake and Smith Pond. While native plantings generally require little management, it is common for non-natives and other aggressive plants to try to establish themselves within the plantings. This can become a problem if not timely addressed, as these invasives try to out-compete the natives. Although the planted buffers at both Lower Penn and Smith Pond are flourishing with a wide variety of healthy, hardy plants, some invasives are present. The City hopes that aggressively tackling this problem now will help to promote an even healthier buffer in the future. Management efforts will include a combination of hand-pulling, cutting and chemical spot-spraying. The project will start in September 2006 and take about a year to complete. Bush Lake aquatic vegetation researchEurasian watermilfoil and Curly-leaf pondweed, both aquatic invasive species, are present in Bush Lake. Recently Eurasian watermilfoil and Curly-leaf pondweed were reported to have proliferated. Bush Lake is a unique and special resource to the community and the City has been monitoring the current conditions and the growth potential of Eurasian watermilfoil and Curly-leaf pondweed in Bush Lake. Data indicate the potential for light to moderate curly-leaf growth over most of the littoral zone. However, milfoil has the potential to produce heavy growth in several areas, mainly in the southern and southeastern parts of the lake. Current conditions were assessed using the point intercept method. Milfoil growth was observed at 41% of the sample sites with heavy milfoil growth observed at only 3% of the sample sites. Curly-leaf pondweed growth was light and sporadic throughout the lake. Comparing current data with previous data from a 2006 U.S. Army Corps of Engineers report it appears the Bush Lake aquatic plant community is fairly stable with typical annual variations.
For more information, contact:
Scott Anderson, Engineering Resources HOME | Management plans | Map | Ways to protect | Links
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