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Department Approval: REQUEST FOR COUNCIL ACTION Manager Reviewed: �� DATE: 10111/04 ITEM: 3.e Agenda Section: Consent Item Description: Approving professional services contract for design and construction of Ladyslipper Park Water Quality Improvements Background: The City of Roseville is anticipatingreconstructionof South Owasso Boulevard as a part of our 2005 Pavement Reconstructionprogram. Ladyslipper Park is directly adjacent to this project. The vast majority of this park is wetland area containing emergent cattail and deciduous scrub shrub vegetation, the north end of the park contains the southeasternmostbay of Lake Owasso. The wetland is protected under the Minnesota Department of Natural Resources Protected waters and wetlands programs and designated as 62-137W. This wetland area was the subject of two in depth reports conducted by the City of Roseville and Grass Lake Watershed Management Organization (GLWMO) in the early 1990s. Both of these reports were the result of concerns brought to the City by adj acent property owners. Approximately 160 acres of single family residential property drain to this wetland through a drainage ditch that cuts through the park in a north south direction conveying storm water runoff northerly to Lake Owasso. This ditch was constructed in 1971, as a canoe access to Lake Owasso. In the 1991 Lake Survey report, it was determined that the removal efficiencyof this system is very limited. Only 30 to 50% of suspended solids and 9% of the total phosphorus were removed before being discharged into Lake Owasso. Phosphorusremoval is importantbecause ofthe role it plays as a nutrient for algal growth in the receivingwater bodies. This subwatershed is the largest remaining untreated direct discharge of stormwater into Lake Owasso. GLWMO as well as the City of Roseville, have included the reduction of sediment and phosphorus loading in Lake Owasso as a primary goal in their comprehensive storm water management plans. In 1993, the City of Roseville received a petition from the residents in the Woodlynn Park area to consider public improvements to enhance the south bay of Lake Owasso. A feasibility study was completed in late 1993 with a recommendation to constructwater qualityponds within Ladyslipper Park just to the north of S. Owasso Boulevard. The City did not move forward with the improvementsin 1993 becausethere was another project that was consideredto be a higherpriority. That improvement was to the American Legion Park wetland. This wetland complex was responsible for 30% of the phosphorous loading in Lake Owasso. Those water quality improvements were completed, with the intention to revisit LadyslipperPark wetland improvementswhen the City reconstructedS. Owasso Blvd. The design discussed in the 1993 feasibilityreport proposes the excavation of two sedimentation basins within the Ladyslipper Park wetland. These excavated areas are approximately 1.6 acres in size. The Minnesota Environmental Quality Board requires that an Environmental Assessment Worksheet (EAW) be prepared whenever impacts of over an acre are proposed within a DNR