Effects of Stormwater Pipe Size and Rainfall on Sediment and Nutrients Delivered to a Coastal Bayou

Water Environ Res. 2015 Sep;87(9):796-804. doi: 10.2175/106143015X14362865226275.

Abstract

Pollutants discharged from stormwater pipes can cause water quality and ecosystem problems in coastal bayous. A study was conducted to characterize sediment and nutrients discharged by small and large (< 20 cm and >20 cm in internal diameters, respectively) pipes under different rainfall intensities (< 2.54 cm and > 2.54 cm, respectively). Results showed that large pipes had greater discharge than small pipes. Pollutants concentrations did not vary by pipe size. Large pipes had greater loads of TSS (138.2 vs. 24.0 mg/s), NO3(-) (5.54 vs. 2.74 mg/s), and NH4(+) (0.39 vs. 0.19 mg/s) than small pipes. Neither discharge nor constituents varied by rainfall events. Pipe size may be a useful metric for estimating loads to a system. Nutrient reduction efforts should be directed to reducing the dissolved nutrient pools, while stormwater management efforts should be directed to reducing pipe freshwater discharge volumes that drive constituent loads.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Environmental Monitoring
  • Mississippi
  • Rain / chemistry*
  • Water Movements*
  • Water Pollutants, Chemical / analysis*
  • Water Quality*

Substances

  • Water Pollutants, Chemical