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b. Storm Sewer Improvements: Several governmental units hold jurisdictional authority over surface and ground water for the site. The project site lies within the Rice Creek Watershed District (RCWD), and roadway improvements take place within the City of Lino Lakes' and Mn /DOT's right of way. The Minnesota Pollution Control Agency (MPCA) regulates both storm water and erosion through the National Pollution Discharge Elimination System (NPDES) Phase II rules and the Stormwater Program for Municipal Separate Storm Sewer Systems (MS4). Each has regulations concerning floodplains, storm water discharge rates, and storm water treatment. In general, the rules of the RCWD govern most of the water resource - related design and are the most stringent. While both the RCWD and MPCA require the use of storm water treatment BMPs to improve the quality of storm water prior to discharge to receiving waters, the RCWD rules are most restrictive and, thus, have been used for design. In addition, the City of Lino Lakes' and Mn /DOT's Stormwater Pollution Prevention Plan (SWPPP) require demonstration that no degradation to surface waters occurs. The RCWD and MPCA require that storm water treatment BMPs be utilized to treat runoff from the site. Storm water treatment ponds have typically been the BMP of choice where possible. This project presents opportunity for their use. Adequate dead pool storage must meet RCWD requirements by utilizing the 2.5 inch storm event for the proposed hydrologic conditions. Infiltration or filtration BMPs are also widely accepted as excellent water quality BMPs; however, the presence of high ground water throughout the site precludes the use of this type of treatment method. To meet RCWD and MPCA requirements, treatment ponds were designed to settle and treat pollutants from adjacent roadways. By implementing these stormwater treatment pond measures, it is expected that the water quality of the discharge from the site will meet non - degradation requirements when compared to the existing condition. c. Sanitary Improvements: The project includes an extension of a 21 inch PVC sanitary line north of CSAH 14 at 21st Street and minor adjustments to manholes. d. Watermain Improvements: The project includes an extension of a 16 inch DIP watermain north of CSAH 14 at 21st Street and minor adjustments to valves. CSAH 14 & I -35E Interchange Project Feasibility Study July 2009 Page 9