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B. Sanitary Sewer City records show the sanitary sewer system was installed during the various phases of the residential development. The project area is served mainly by polyvinyl chloride (PVC) pipe and a few vitrified clay pipe (VCP) and reinforced concrete pipe (RCP) sanitary sewer mains. The sanitary sewer is part of sewer district M059 and is all 8-inch diameter sanitary sewer, with the exception of James Avenue which is 12-inch diameter. The comprehensive sewer plan does not identify changes in pipe diameter within the project area. The existing condition of the sanitary sewer system was documented by videotaping of the sewer main. City Public Works staff completed this televised documentation in the spring of 2023. The televising revealed that the pipes were in generally good condition, with approximately nine locations that were identified as needing rehabilitation or repairs. Some of the defects found in the sanitary sewer were cracked pipes, offset joints, pipe sags, defective service connections and groundwater infiltration at joints. The groundwater infiltration adds to the volume of wastewater being treated and subsequently the wastewater treatment costs. Sags and offset joints can interfere with the flow of sewage, creating a higher maintenance cost. C. Watermain City records indicate that all existing watermain within the project area is Ductile Iron Pipe (DIP), varying in size between 6-inch, 8-inch, or 12-inch diameters. The water main system runs the entire length of the project area and connects to a looped system at most roadway connections. There are a few streets within, or connecting to, the project area that are not part of a looped system, including Arden Vista Court, Colleen Court, Colleen Circle, Briarknoll Circle, Indian Oaks Court, Indian Oaks Trail, Dawn Circle, and Royal Lane. A review of the City's watermain break historical records did not identify any breaks or leaks in the project area other than isolated leaky valves and bent valve boxes. The existing watermain on James Avenue is 6-inches in diameter but connects to 8-inch diameter watermain to the south on Indian Oaks Trail, 8-inch diameter dead end watermain to the west on Indian Oaks Court, and 12-inch diameter watermain to the north on Colleen Avenue. The smaller diameter on James Avenue constricts the flows beyond James Avenue, particularly to Indian Oaks Court because it is not a looped system. D. Storm Sewer City records indicate that the existing storm sewer within the project area is primarily comprised of RCP and ranges in diameter from 12-inch to 54-inch. The existing drainage pattern within the project area is generally from the exterior project limits to the storm water ponds located around the project area. Drainage is conveyed overland or through storm sewers and discharges into these existing stormwater ponds. 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 necessary. Storm sewer televising identified four locations with joint separation, cracking, offset joints, and/or pipe sags that will need to be addressed. E. Stormwater Ponds There are various stormwater ponds throughout the project area that provide outlet storage areas to the storm sewer system and overland drainage, as discussed above. Over time, stormwater ponds will collect sediment which reduces their working capacities. Specifically, two of these ponds have been identified by city staff to have significant accumulated sediment. The first pond is located between McClung Drive and Briarknoll Circle, just north of the bituminous trail. The second pond is located south of Colleen Avenue, just west of Hamline Avenue North, however, only a portion of this pond is within city easement (the rest Prepared by: Bolton & Menk, Inc. 2024 PMP Street & Utility Improvements I OT1.130168 EXISTING CONDITIONS Page 3