Technical Results
Post-construction Impacts on Water Quality
Construction | Post-construction
In general, concentrations of pollutants in the traditional subdivision
either decreased or did not change after construction (Figure 1).
However, in the LID subdivision, concentrations of some pollutants
decreased, but others such as TSS, NO3-N,
and TP,
increased (Figure 1). For pollutant mass export, the large flow increases
in the traditional subdivision caused large increases in all pollutants
measured (Figure 2). TSS and TP mass export increased from the LID
subdivision, but increases were much less than from the traditional
subdivision.
 |
 |
| Figure 1. Significant changes in pollutant
concentration, after construction was completed. Units are
mg/L for NO3-N, NH3-N, TKN, TP, BOD and μg/L
for Cu, Pb, and Zn. |
Figure 2. Significant changes in mass
export (kg/ha/year) after construction was completed. |
|
