HR: 16:30h
AN: H14A-05 [Abstracts]
TI: Fecal-borne bacteria in stormwater and treatment systems in coastal New Hampshire
AU: * Jones, S H
EM: shj@cisunix.unh.edu
AF: University of New Hampshire, Jackson Estuarine Laboratory
85 Adams Point Rd., Durham, NH 03824 United States
AB:
Bacterial contamination is the most common use limitation in New Hampshire's coastal waters. Past studies have shown
consistently elevated levels of fecal-borne bacteria in surface waters occur during and following runoff events. Follow-up
investigations have shown many stormwater conduits in urban areas that discharge directly into tidal rivers to contain high
levels of bacteria, even during dry weather conditions. One of the results of these conditions is the need to close
shellfishing waters throughout coastal New Hampshire, especially in Hampton Harbor, following rainfall events.
Several recent studies have involved investigation of stormwater treatment system impacts on bacterial pollutants. Influent
and effluent water samples from parking lot and storm drain treatment systems, runoff from urban streets, effluent from urban storm drains and receiving water samples were collected during different stages of stormwater runoff and analyzed for fecal
coliforms, Escherichia coli and enterococci. E. coli isolates from one storm drain system were also ribotyped to
identify source species.
The stormwater treatment systems showed different capabilities for removing bacteria. Most were inconsistent at removing
bacteria while others showed evidence of possible re-growth of bacteria between storms, especially during warmer weather.
Re-growth or illicit connections appear to impact effluent bacterial levels in many urban storm drains. The source species
identified for E. coli isolates in one storm drain changed between different stages of a storm event, reflecting runoff dynamics and human behavior patterns. Further work is focused on identifying the most significant sources of bacterial
contaminants in receiving waters to help focus ongoing pollution abatement measures.
DE: 4840 Microbiology
DE: 4857 Pollution
SC: Hydrology [H]
MN: 2005 Joint Assembly