Evaluation of the Effects of Urbanization on Stormwater Runoff and Quality.

摘要

Results of an analysis of stormwater runoff and quality from four small urban watersheds in Knoxville,Tennessee,are presented in two parts:Part 1is on Stormwater Hydrographs and Part 2is on Stormwater Quality. A third part presents the mathematical models developed in the course of the study for simulating storm hydrographs,suspended sediment pollutographs and loads,and sediment delivery ratios. There is apparently a wide range of effects of dustfall and urban stormwater quality on a contaminant-by-contaminant basis. Certain constituents such as COD,Hg,Cl,Pb, SiO2, PO4,and As,significantly influence stormwater quality. Likewise COD,Hg,Cl,As,and PO4levels found in the stormwater were caused primarily by dustfall. There are two distinct but overlapping groups of contaminants found in the urban watershed. One group is the minerals and solids which have relatively constant concentrations from storm to storm and the other group is heavy metals,nutrients,and COD which have decreasing concentration with increasing runoff.