Agenda - Council - 02/26/2019 - Laserfiche WebLink

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The combined projected average daily flow for the Rum River District is 3.154 MGD with peak flows reaching 7.723 MGD. Therefore, there appears to be sufficient capacity in the MUSA regional interceptor which is designed for a peak flow of 8 MGD. Again, it is recommended that the City reevaluates their MCES allocation of the interceptor capacity prior to performing an update of their Comprehensive Sewer Plan. Combined City of Ramsey Flows. Table 18.7 below shows the total future average daily wastewater flow for the entire City to be 7.3 MGD with a peak hourly flow of 16.5 MGD. It should be noted that these flows assume the maximum possible density at final build - out and, therefore, represent the most conservative scenario. As a result, it appears that the existing interceptors are large enough to carry the projected future average daily flows, as well as the projected future peak hourly flows. In addition, it appears that the future average daily wastewater flow is above the MCES allocated flow of 2.8 MGD, as well as the higher allocation of 3.8 MGD. Table 18.7: Projected Maximum Wastewater Flows for 2020 Sub -district Future Average Daily Flow (MGD) Future Peak Hourly Flow (MGD) Average Annual Flow (MG) Mississippi River District 4.1 8.75 1,497 Rum River District 3.2 7.72 1,168 TOTAL 7.3 16.5 2,665 Summary of Environmental Impact. The provision of sanitary sewage collection and transport to a treatment facility is a normal urban service provided by a community as its urban area develops. There is no adverse environmental impact expected as long as the plan for provision of this service is followed according to the City's 2001 Comprehensive Plan, as amended in 2002 and coordinated with MCES. Mitigation element - Combined future flows for land within the Urban Growth Boundary for both Districts appears to be about 4.3 MGD (about 3.0 MGD from the Mississippi River District and 1.3 MGD from the Rum River District). The 1991 Comprehensive Sewer Plan estimated these flows to be about 3.8 MGD. Therefore, increased flows due to the RTC development appear to be about 0.5 MGD greater than planned in 1991. Both the wastewater flows and the projected loadings from the RTC development can be effectively transported and treated by the MCES system. However, future development and resulting flows need to stay within the current 3.8 MGD allotment allowed by MCES until such time as more allocation is available. In general, however, total projected flows for the City are within the ranges of those estimated in the City's 2001 Comprehensive Plan, as amended in 2002. Therefore, it does not appear that there is any cause for specific remediation actions. 18-10