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Prepared by: Bolton & Menk, Inc. EXISTING CONDITIONS 2026 PMP Street & Utility Improvements ǀ 25X.137753 Page 4 Beyond the County Road 96 watermain, a review of the City’s watermain break historical records did not identify any further breaks or leaks in the project area other than isolated leaky valves, damaged valves, damaged hydrants, and bent valve boxes. This indicates the majority of the watermain pipes are still in good operating condition. City public works staff identified the need for an additional hydrant along Amble Drive and also identified a number of curb stop boxes that are either buried or sticking out of the ground. The comprehensive water plan does not identify changes in pipe diameter within the project area. Storm Sewer The existing drainage system has limited storm sewer with outlets into Karth Lake and storm ponds located along Lexington Avenue and CSAH 96. City records indicate that the existing storm sewer within the project area is primarily comprised of Reinforced Concrete Pipe (RCP). The existing drainage pattern within the project area is generally from the exterior project limits in towards Karth Lake. Some of the existing storm outlet aprons are partially or fully submerged within Karth Lake. The City’s Public Works staff completed inspections of the existing storm sewer and found these pipes to be in good condition, with minor manhole repairs and replacement of existing castings as necessary. Storm sewer televising identified approximately eight locations with joint separation, cracking, and/or offset joints, that will need to be addressed. Stormwater Management Existing grit chambers are located in all storm systems prior to the storm outlets, except the Karth Lake Circle outlet, in an effort to collect sediment and debris before discharging into Karth Lake. A significant amount of overland drainage from the industrial/commercial properties to the south enters Karth Lake along the southeast bank. A previous project was completed in this area to reduce erosion by stabilizing the slope and providing for a culvert crossing under the trails south of Karth Lake. There are a total of five storm water outlet locations included in this project scope within Karth Lake which have accumulated sediment over time (there are six total outlet locations into the lake). These delta locations have collected sediment over time that entered the lake from the storm sewer system. Karth Lake Karth Lake is a natural occurring lake and is a Public Water as identified by the Minnesota Department of Natural Resources (MnDNR) on their Public Waters Inventory (PWI). There is no emergency overflow for the lake where water can escape to during high water levels without causing flooding conditions. The 100-year floodplain elevation is 938.19 (NAVD 88). As a result, the City installed and operates a manually deployed pump and forcemain system to manage the lake level. The pumped outlet consists of a pump system with a sump pump mounted on a floating raft that pumps through a 6-inch forcemain to the southwest where it outlets in the city storm sewer system at the north side of the Cummings Park Drive cul- de-sac. This system was installed in the early 2000’s and is permitted through the MnDNR to maintain lake levels between an elevation of 934.0 and 936.0. Trails Existing trails exist within Cummings Park and along the south side of Cummings Park Drive. City staff identified trail segments within Cummings Park, extending west from Lexington Avenue, and along the south side of Cummings Park Drive on the east end, which are in particularly poor condition. These trails are constructed of bituminous pavement and are DRAFT