Sodus Creek East (Glenmark Creek) (2003 Study)
Identifying Pollutant Sources to Glenmark Creek
In Wayne County, at Sodus Bay, we have performed annual monitoring of nutrients and discharge allowed us to prioritize the sub-watersheds and their streams to identify the stream/sub-watershed having the greatest impact on the Bay. In this case, Glenmark Creek accounted for over 80% of the phosphorus entering the Bay.
Systematic sampling of the watershed was undertaken to determine the origin(s) of the
phosphorus loss from this watershed. Several different sources were eventually identified.
Figure 2 shows the sampling pattern that was developed, and how a small but important
source of phosphorus was identified. In a previous sampling, a site identified as MAG1 at the base of a second-order tributary showed relatively high levels of several pollutants including phosphorus (35.6 mgP/L) as compared to the main stem of Glenmark Creek (site MAG1X, 15.8 mgP/L). By sampling systematically at various locations along thestem of this secondorder creek, and above its junction with a primary-order stream,we were able to track the high phosphorus concentrations to a failed septic system from a home above Site MAG1G.
Upon closer investigation, leachate was observed emanating from the ground and moving down the stream bank into the creek. Phosphorus concentrations at this location reached nearly 93 mgP/L. Once this source was targeted, the Wayne County SWCD was able to advise the homeowner on how to remedy the problem.
Determining sources of pollutants and their magnitude is prerequisite to making cost effective land management and remedial action decisions. Stressed stream analysis uses an iterative measurement process to reduce the likelihood of costly miscalculations based on assumptions of nutrient sources and modeling. We have found this process provides hard data that enhances the ability of concerned local groups to obtain external funding for remedial or demonstration projects.
In Wayne County, for example, funds were secured for a constructed wetland to remediate milkhouse wastes identified by stressed stream analysis. At Canandaigua Lake, funds were secured for a segment analysis after the priority ranking phase identified one sub-watershed (Sucker Brook) as providing a major load of phosphorus into the lake. In another county, high losses of sodium from a watershed were attributed through segment analysis to a poorly managed deicing salt pile, which has now been completely enclosed.
By following the stressed stream analysis approach to identify and prioritize pollution problems, managers are able to make cost-effective decisions with increased confidence. Stressed stream analysis recognizes the fundamental importance of defining the problem clearly before determining the solution. It is a proactive tool that recognizes the long-term value of stewardship of natural resources.
Joseph C. Makarewicz /Department of Biological Sciences, Center
for Applied Aquatic Science and Aquaculture, SUNY Brockport, Brockport, New York