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Ms. Katie Larsen December 26 , 2013 Page 3 3 11. Sanitary sewer manhole No. 6 includes an interior drop of 6.45 feet. The maximum drop allowed is 18 -inches. The grade on the sanitary pipe from manhole No. 13 to manhole No. 6 needs to be adjusted accordingly. 12. The minimum storm sewer pipe size is 15 -inches in diameter. 13. All storm sewer must be RCP. 14. Storm sewer design calculations must be provided for review and approval prior to final plat approval. Profile drawings of public utilities will also be needed with this submittal. 15. City detail plates must be incorporated into the plan set. STORMWATER MANAGEMENT 1. The applicant must present required and proposed pond volumes in the Stormwater Management narrative. Based on HydroCAD Report, i t appears that all ponds are able to meet the criteria. 2. Provide calculations for 10 -day snowmelt and demonstrate compliance with rate control for this design event. 3. Permits for wetland impacts and replacement plan must be approved by RCWD. 4. Note elevatio n of floodplain on plans or in narrative. If the site’s elevations are not within regulated floodplain elevations, this should be noted in narrative. If fill is proposed within floodplain areas, provide cut / fill volumes within the floodplain to demonst rate that no net fill will occur within the floodplain. 5. Note that ATLAS 14 precipitation was used for analysis in Stormwater Management Report narrative for future reference. 6. Curve Numbers used in the HydroCAD model should match standards outlined in RCW D Rules. 7. Address how runoff from proposed Old Birch Street (Subcatchment 1) to the intersection of existing Old Birch Street will be addressed. 8. Address wetland impacts and provide drainage design (e.g. culvert and EOF) for the proposed trail that crosse s Wetland F -3.