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where: Q, AI = Known flow from SWMM downstream from location 2 Drainage area input to SWMM at point downstream oflocation 2 Drainage area at point location 2 (planimetered) Flow at location 2 = A, Q, = = Table 8 shows the flow at each of the sub-routes or City drainage facilities for the 2-year, 5-year, la-year, 50-year, and lOa-year storm events, Table 6 provides the capacity of the major storm sewers in the City of Aspen, which correspond to a drainage reach, For the purposes of this study a major storm sewer was defined as having an 18- inch diameter or greater, The exception to this was the 18- inch storm sewer on Hopkins from Hunter to Spring. Due to its short length and small drainage area, this storm sewer was defmed as a lateral and was not included in the analysis. Table 7 supplies the capacity of the street flow along the drainage reaches, It was assumed, forthe purpose of this preliminary analysis, that the street flow would be limited to a 6-inch depth at the curb, No flow into the adjacent yards would be permitted, It was further assumed that the cross slope of the streets was 2%, The street width was scaled from the Figures 7 and 8, If the street does not have curb and gutters and runoff would flow into garages along the street, there will actually be no street flow capacity, and the total capacity will be the storm sewer cl1pacity . F, RESULTS Based on a comparison of the magnitude of the flow events for a given return period to the capacity of the existing drainage facilities it appears that: The capacity of the drainage system along Original Street is insufficient to convey the 50-year and the laO-year storm events, The storm sewer, alone, should be able to transport the 5-year flow event. The drainage facilities along Spring Street south of Main Street are unknown at this time, The 5 ; :.- ,.-..11 ~--I ' , , ,