Laserfiche WebLink
Basin Information and Lag Time Computation <br />Project Title: Parkdale Granite Quarry <br />Catchment ID: D <br />1. Catchment Hydrologic Data <br />Catchment ID = D <br />Area = 19.02 Acres <br />Area = 0.0297 Square Miles <br />Percent Imperviousness = 5.00 % <br />NRCS Soil Type = D A, B, C, or D <br />II. Analysis of Flow Time (Time of Concentration Tc) for a Catchment <br />Using SCS Lag Equation (1975) <br />Developed for small (<2000 acres) watersheds <br />Equation assumes Tc = 1.67"Basin Lag <br />Tc = 100L08[(1000/CN)-9]0.7 / (1900So.) <br />Avg. slope for longest watercourse S = 13.9 % <br />SCS Curve No. CN = 84 Land use assumed to be Pasture/Range in FAIR condition <br />Length of Water Course L = 1,295 feet <br />Tc = 9 minutes