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page 12  Examine the merits of relocating project elements to address, varying soil and contamination conditions. A Stormwater Pollution Prevention Plan (SWPPP) will need to be prepared in accordance with NPDES guidelines and the City of Saint Anthony Village’s Stormwater Management criteria, and will be required to be submitted and approved prior to construction. Grading, drainage, and erosion control measures must be consistent with Mississippi Watershed Management Organization’s Management Plan and the City of Saint Anthony Village’s Surface Water Management Plan. There will be no anticipated downstream environmental effects from the proposed project based on the project needing to meet state and local requirements. iii. Water appropriation - Describe if the project proposes to appropriate surface or groundwater (including dewatering). Describe the source, quantity, duration, use and purpose of the water use and if a DNR water appropriation permit is required. Describe any well abandonment. If connecting to an existing municipal water supply, identify the wells to be used as a water source and any effects on, or required expansion of, municipal water infrastructure. Discuss environmental effects from water appropriation, including an assessment of the water resources available for appropriation. Identify any measures to avoid, minimize, or mitigate environmental effects from the water appropriation. Water Supply and Infrastructure The proposed development will increase average and maximum day water demands by approximately 140,000 and 300,000 gallons per day, respectively. The additional water demands were calculated as 180 gallons per unit per day for average flows, with the peak factor of 2.14 determined from historic water usage data. These calculations resulted in an average daily demand of 105 gallons per minute and a peak daily demand of 225 gallons per minute. These flows would be delivered from the City’s existing water treatment plant (WTP), through the 10-inch trunk main that runs along Silver Lake Road to Kenzie Terrace. The City’s existing water storage and supply will be adequate in managing the increased water demand from this proposed development. It is planned that the development’s service connections will be located along Kenzie Terrace to provide the maximum available fire flow rates. Without knowing more information regarding the proposed building’s interior sprinkler system flow rate requirements, a minimum fire flow rate for the development was conservatively assumed to be 3,500 gallons per minute (gpm). This fire flow was approximated based on the Insurance Service Office (ISO) standards and recommendations. The City’s existing water system was modeled to determine if the existing infrastructure would be adequate in providing the required minimum fire flow rate. As the system currently exists, the available flow rate at the proposed location is approximately 2,300 gpm which is below the ISO’s requirement. 47