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Prepared by: Bolton & Menk, Inc. EXISTING CONDITIONS 2026 PMP Street & Utility Improvements ǀ 25X.137753 Page 3 Alligator cracking in pavement is an indicator of potential subgrade problems. The street pavements are in generally poor condition and have seen an increased need for maintenance operations which are all indications that the street pavements are in need of varying levels of rehabilitation. Cores with soil borings and a geotechnical evaluation were completed throughout the project area by Braun Intertec and the report is included in Appendix F. The existing bituminous pavement thickness generally ranges from 3.5 to 5.5 inches with a few select areas of thicker pavement, up to 11 inches. The existing aggregate base thickness generally ranges from 5 to 8 inches, with a few areas of thicker aggregate base and a couple of locations of thinner aggregate base. The areas with thinner aggregate base may require additional stabilization and will need to be identified during construction. Existing subgrade soils found beneath the aggregate base are predominantly a mixture of clayey and sandy soils, with low organic content indicating the material is suitable for reuse onsite during utility work. Sanitary Sewer City records show the sanitary sewer system was installed during the various phases of development. The project area is served primarily by polyvinyl chloride (PVC) pipe sanitary sewer mains. The gravity sanitary sewer is part of sewer district M059, with the sewer along Cummings Park Drive being part of sewer district M051, and is predominately 8-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 2025. The televising revealed that the pipes were in generally good condition, with approximately four locations that were identified as needing rehabilitation or repairs. A project questionnaire to property owners indicated that some properties are experiencing sewer service issues but they primarily appear to be issues related to the private service line itself and not the connection to the main. Some of the defects found in the sanitary sewer were pipe deflections, root intrusions, gasket issues, 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. The project area also includes sanitary Lift Station 13, located at the northwest corner of Pleasant Drive and Karth Lake Drive. The lift station pumps to a 6-inch DIP forcemain which runs west and outlets to the gravity sanitary sewer system on the west side of Hamline Avenue, just south of Karth Lake Circle. Lift Station 13 was last rehabilitated in 2023 and is in excellent condition and the forcemain has no history of breaks. Watermain City records indicate that existing watermain within the project area is primarily Ductile Iron Pipe (DIP), varying in size between 6-inches and 8-inches, with 12-inch diameter pipe located on Cummings Park Drive. The watermain system runs throughout the project area and connects to a looped system at most roadway connections. Additionally, there is a watermain loop within utility easements that serves a few properties north of Karth Lake Drive, along County Road 96. This looped watermain runs approximately under the south curb line of County Road 96 and has had a history of some breaks. These breaks cause impacts to the county road which adds additional coordination and expense to the repairs. DRAFT