Urban Stormwater Runoff Contamination Associated with Gutter and Pipe Material Degradation

Abstract

The purpose of this research was to investigate how different pipe, gutter, and storage tank materials, time of contact, and pH affect water quality. The tests were conducted using a series of controlled laboratory experiments for a period of three months by immersing sections of the test materials in large quantities of pH buffer solutions made using locally collected roof runoff and storm drain inlet water. The tests were conducted at pH 5 and pH 8. Water samples were periodically collected and then analyzed for a broad range of metallic and nutrient constituents and toxicity utilizing Microtox procedure. Copper release from copper gutters increased with decreased pH. The highest concentrations of zinc were observed from galvanized materials. Decreasing the pH increased zinc concentration from galvanized steel materials during the first 27 hours of exposure. Galvanized steel materials were the only source of lead concentrations.

The Effects of Water Quality Characteristics on Pollutant Releases from Drainage Materials

“…The copper releases increased with the exposure time; greater concentrations were observed for the samples in the bay water possibly due to the higher content of the chloride ion which causes corrosion (Corvo, 2005;Gabriel and Moran, 1998). .16 Group box plot for copper release in mg/m 2 for copper materials immersed in bay and river waters (Ogburn, 2013). Figure 13.17 shows zinc releases from various gutter and pipe materials under controlled pH conditions.…”

“…Figure 13.9 and Figure 13.10 show zinc releases resulted from various gutter and pipe materials during the unbuffered experiments. Figure 13.9 Total zinc losses in containers with bay water (Ogburn, 2013). Figure 13.10 Total zinc losses in containers with river water (Ogburn, 2013).…”

“…Figure 13.9 Total zinc losses in containers with bay water (Ogburn, 2013). Figure 13.10 Total zinc losses in containers with river water (Ogburn, 2013).…”

“…Lead releases resulting from different materials during the buffered tests are shown in Figure 13.11 and Figure 13.12. Figure 13.11 Total lead loss in containers with pH 5 water (Ogburn, 2013). Figure 13.12 Total lead losses in containers with pH 8 water (Ogburn, 2013).…”

“…For galvanized steel materials, lead releases were greater in samples under controlled pH conditions compared to samples under natural pH conditions. .14 Total lead losses in containers with river water (Ogburn, 2013). Table 13.1 shows zinc, lead and copper releases from the most significant sources after 3 month exposure.…”