State Water Resources Research Institute Program
Project ID: 2009DE159B
Title: Investigation of Source and Dynamics of Bacterial Contamination in a Coastal Lagoon
Project Type: Research
Start Date: 3/01/2009
End Date: 2/28/2010
Congressional District: At large
Focus Categories: Water Quality, Non Point Pollution, Toxic Substances
Keywords: Bacterial contamination, salt-water ponds, E. coli, source tracking
Principal Investigators: Chan, Clara; Olson, Emily
Federal Funds: $ 1,500
Non-Federal Matching Funds: $ 3,000
Abstract: The purpose of this internship to study the multi-tiered relationships between various factors contributing to E. coli trends in Lake Louise, a salt-water tidal lagoon in Point Pleasant Beach, New Jersey. Lake Louise is a subsidiary of the Manasquan River and Barnegat Bay estuary systems along the New Jersey coast (Figure 1). Water quality in Lake Louise is measured by the amounts of coliform, specifically E. coli, the standard indicator for bacterial contamination, present in water samples. Water quality tests that were contracted out to a certified lab showed wide swings in E. coli counts in the lake from double digits to up to 2000 parts per million during the summer months (local beaches generally close at around 200ppm). Why do test results come back so high, and how does this impact the overall water quality of the lake?
There are several factors believed to contribute to the high levels of E. coli found in the lake at times. There are 80 homes located on lakefront property, and Lake Louise is surrounded by a local community of 5000 in winter that swells to over 50,000 in summer. It is suspected that there is sewage leaching into the lake due to broken sewer pipes, and that this increase in population and therefore sewerage usage detracts from the lake's water quality. Lake Louise is also connected to neighboring Silver Lake and Lake of the Lilies via two 36" conduits (Figure 1). Both neighboring lakes have a large water fowl population and the two lakes' only water turnover (other than groundwater sources) is provided through this pipe. The outgoing tide draws water from the two lakes into Lake Louise, which is suspected to negatively impact the water quality of Lake Louise. All three lakes also receive runoff from streets and yards after heavy rains, which, because of the sandy soil, also seep into the ground and may cause contaminated groundwater to permeate into the lake. All of these factors will be investigated as possible sources of contamination, as measured by E. coli population counts. Since Lake Louise is used for recreational water sports by residents, it is important to have a thorough study of the lake's water quality in order to provide accurate indications of the safety of the water for human usage. The town of Point Pleasant Beach is also interested in the results of the study not only as a record for the town's files, but also as an opportunity to educate all residents about water quality and the health of the town's lakes.
This project will utilize microbial sampling and analyses, as well as basic hydrogeologic and geochemical observations to identify sources of contamination and understand how the hydrology relates to contamination levels. The main data collection will involve measuring the amount of E. coli found at specific sites on a weekly basis, or after opportunistic events such as rainfall. It seeks to determine the effects of the relationship between the lakes and tides on water quality, and also to track the effects of specific environmental conditions and changes in standard conditions. Several variables, as outlined above, will be pinpointed and specifically tested as potential sources of contamination. The project will be dynamic: testing procedures, locations, and variables may be changed or added as prior results indicate they should be. Possible solutions to these problems will be investigated while residents, both permanent and seasonal, are educated about the water quality of the Lake and their impact on it. Finally, the lake is in the permit process to be dredged. This study may support the need for dredging on the premise that, if dredged, there would be a greater volume of water flushed out during tide changes resulting in cleaner water in the lake. Ultimately, this project is intended to help pinpoint, fix, and educate about some of the serious issues pertaining to E. coli and its relationship to the health of Lake Louise.
Progress/Completion Report, 2009, PDF