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Guptil Site, 04-RS-001 Apri128,2004 Page 5 The results of the modeling are summarized in Table 3. APPENDIX D Storm Event E�sting Conditions Praposed Conditions cfs f 2 1.57 1.74 5 3.09 1.79 10 437 1.83 100 8.44 1.98 As illustrated in Table 3, it appears that the proposed peak discharge rates for all storm events except the 2-yr will be less than e�stingrates. It should be noted that the high water level obtained from the storage volume modeled v� approximately 892 feet. The newly configured pond can be expected to ha�e a high water level somewhere between 892 feet and the existing high water level of 894 feet. Nevertheless, the exact size and configuration of the pond outlet will need to be field verified to better determine proposed discharge rates. The outlet may have to be modified due to the changes in the storage volume. It is possible that the new pond can meet the CRWD's requirementthatthe existingpeak dischargerates forthe 2-, 5-,10-, and 100- yr storm events. WATER QUALITY Water quality for the site was evaluated using P$, a water quality modeling tool model for predicting the generation and transport of stormwater runoff pollutants. The portion of the pond indicated as LL�d Storage in Table 2 was incorporated into the model to predict the annual total phosphorus reduction from the site. `T'he results of the P8 model indicatethat approximately 63.5% in annual total phosphorus reduction will be achieved through a pond configured as shown in Table 2. Therefore, this pond is sized appropriately in order to meet the CR WD's requirements for phosphorus reduction for the proposed development SANITARY AND WATER The G�S information provided by the City of Roseville indicates that water main is located along both Elmer Street and McCarrons Boulevard for use for the development. Additionally, sanitary manholes are located within IIt�r Street and within McCarrons Boulevard in front of the parcels that are being considered for redevelopment. Therefore, sanitary and water main will be readily a�ailable for the development. Both these utilities will need to be a�oided when installing a storm sewer across IIt�r Street. CONCLUSION From our analysis, based on the developable area, drainage, and a�ailable utilities, a 40-un.it multi-family developmentwould be well suited forthe Guptil and Elmer Streetparcels. Based on actual wetland and waterbody boundaries and buffers, as well as actual building and parking