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<br /> <br />Feasibility Report <br />2021 Street and Utility Improvement Project <br />City of St. Anthony Village <br />WSB Project No. 015900-000 PAGE 5 <br />3. EXISTING CONDITIONS <br /> <br />3.1 STREET AND UTILITY IMPROVEMENTS <br /> <br />3.1.1 Sanitary Sewer <br /> <br />The existing sanitary sewer system along Skycroft Drive and Croft Drive consists of 9-inch-diameter <br />vitrified clay pipe (VCP) installed in the 1950’s. The joint sealing material in use at that time was <br />typically an oakum and bituminous material. <br /> <br />An internal inspection, with a specially designed television camera, was completed to determine the <br />structural condition of the existing pipe and individual services. The mainline sewer was found to be <br />in fair condition with deificencies such as protruding services, mineral deposits, roots, and offset <br />joints. <br /> <br />In addition, the existing sanitary sewer system flow rates have been monitored in various areas <br />throughout the City as a measure to identify inflow and infiltration (I&I) issues within the City. The <br />monitoring results have revealed there is an increase in sewer flow within the area immediately <br />following rainfall events. This increase in flow is a result of clear water (groundwater or stormwater) <br />entering the sanitary sewer. The source of this clear water is likely due to the connection of <br />foundation drains or sump pumps to the sanitary sewer, aging sanitary sewer main and/or deficient <br />sanitary sewer service pipes from the street to individual homes. <br /> <br />3.1.2 Water Main <br /> <br />The existing water distribution mains along Skycroft Drive and Croft Drive were also installed in the <br />1950’s and consist of 6-inch cast iron pipe (CIP). This system has had numerous breaks over the <br />past few years and breaks will become more likely as the pipes have exceeded 60 years of service. <br />In addition, the cast iron pipes are likely heavily corroded and possibly leaking. <br /> <br />3.1.3 Storm Sewer <br /> <br />Limited storm sewer exists within the proposed project area. Stormwater along Skycroft Drive and <br />Croft Drive is directed with concrete curb and gutter from 33rd Avenue to the storm sewer system on <br />32nd Avenue. <br /> <br />Storm sewer facilities were installed along 32nd Avenue and Croft Drive with the 2020 Street and <br />Utility Improvement Project. The system consists of 21-inch reinforced concrete pipe (RCP) along <br />32nd Avenue from Rankin Road to the Croft Drive cul-de-sac and 24-inch RCP along Croft Drive from <br />32nd Avenue to 31st Avenue and along 31st Avenue from Croft Drive to Old Highway 8. The <br />stormwater eventually outlets to Mirror Lake. <br /> <br />Catch basins were installed on Skycroft Drive and Croft Drive north of the intersections with 32nd <br />Avenue with the 2020 improvements in preparation for the extension of storm sewer to the north. <br /> <br />3.1.4 Streets <br /> <br />Streets within the proposed improvement area are urban, 30-foot-wide roadways with concrete curb <br />and gutter. Skycroft Drive consists of bituminous pavement and Croft Drive consists of concrete <br />pavement for approximately 200 feet near 32nd Avenue and changes to bituminous pavement for the <br />remainder of the road. <br /> <br />Soil borings taken within Skycroft Drive and Croft Drive indicate the underlying soils consists of a <br />sandy clay fill. <br />42