WATER QUALITY AT THE FLCA
Roughly a year ago, we resumed periodic monitoring of the water quality in the FLCA. At three-month intervals, we have taken samples from the Broad Brook at North Farms Road, from Fitzgerald Lake at the canoe launch and the dam, and from two locations in the marsh adjoining Cooke's Pasture to the east of the dam. We then analyzed the samples for pH, dissolved oxygen, alkalinity, and for concentrations of phosphate and nitrate, using relatively simple chemical test kits. The results will be posted on the Broad Brook Coalition web site (www.broadbrookcoalition.org) on a continuing basis.
While most parameters have been within normal limits over the past year, we have consistently observed an abnormally high level of nitrate--between 1.3 and 3.6 parts per million (ppm)--in the Broad Brook at North Farms Road, just before it flows into Fitzgerald Lake. Elevated nitrate levels--0.6 to 1.0 ppm--were also noted in a small stream that enters Fitzgerald Lake near the canoe launch. To be sure our nitrate measurements were accurate, we calibrated them against a sample that was analyzed with high precision by the Environmental Analysis Laboratory at the University of Massachusetts and found that our figures were in satisfactory agreement. Why are high nitrate levels of concern? If too high, they encourage the growth of algae and other plant materials that eventually settle, decompose and, in so doing, reduce the oxygen available to fish and other aquatic organisms that live in the lake.
The presence of nitrate in the Broad Brook likely stems from a storm drain system that serves a large portion of Florence, extending well into the neighborhoods along Bridge Street and North Maple Street. Although not at all apparent to the passerby, the drains empty into the Broad Brook beneath North Farms Road, and any pollutants that are present run directly into Fitzgerald Lake. According to Doug McDonald, environmental planner and stormwater coordinator at the Northampton DPW, the most likely sources of high nitrate levels are runoff from lawn fertilizer and leaky septic systems. To raise awareness that pollutants entering the storm water system ultimately flow into Fitzgerald Lake, McDonald has proposed a collaborative project with the BBC encompassing the installation of storm drain labels and other kinds of educational outreach to residents in the watershed. If you would like to participate in these activities, please contact Bob Zimmermann at 585-0405.
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