Water Quality Monitoring
There are water quality factors that are commonly tested for recreational use of the Norwalk River.
Physical factors, including dissolved oxygen, conductivity (to determine salinity), pH, and temperature, are tested to help assess aquatic habitat for fish. Visual observations such as turbidity, cloudiness, algae, silt and the accumulation of leaf litter are also noted as these factors can degrade fish habitat.
Fecal coliform and Indicator Bacteria (in the form of E. coli) are tested regularly on the Norwalk River and its tributaries during spring and summer months. This is to assess the human health risk and compliance with State WQS during the recreational season.
Some measures are taken at the test site and others require water samples to be processed in the lab using standardized procedures and equipment. Strict protocols for sampling and processing are followed to ensure consistent high quality data. This requires that testing facilities acquire an EPA approved Quality Assurance Project Plan, or QAPP. Data needed for federal, state or municipal purpose to determine use or for specific decision making must be obtained under the quality control of a QAPP. The CTDEEP will use Harbor Watch water quality data together with data obtained from state test sites to determine whether water segments meet State standards.
HarborWatch Water Quality Monitoring Program
HarborWatch (HW) is a local volunteer water quality monitoring program at EarthPlace in Westport, CT. Under the Direction of Dick Harris, the program maintains and operates two CT State certified bacteria laboratories with an EPA approved Quality Assurance Project Plan. They offer water quality testing and monitoring services for local rivers, harbors and Long Island Sound.
Harbor Watch has a long history of working together with watershed municipalities and communities to increase awareness, encourage stewardship and resolve water quality issues. They are supported with grants, town allocations, donations and volunteers.
Over the past 16 years, Harbor Watch has been engaged in an active monitoring program on the Norwalk River and its tributaries. There are 20 established sampling sites, along the main stem from the Norwalk Harbor to the headwaters in Ridgefield, which are tested regularly throughout the year. Regular sampling sites are also established on the Silvermine River and Comstock Brook. If warranted, other sampling sites are temporarily added to help isolate suspected pollution sources.
Water Quality Reporting
Harbor Watch issues detailed reports each spring and fall on the data collected from river samples. These Water Quality Data Reports include maps, data tables, graphs and detailed discussion on E. coli bacteria levels (indicator bacteria), conductivity and dissolved oxygen.
Thanks to the dedication of the Harbor Watch Program and the consistency of their high quality work, the Norwalk River Watershed Initiative has been able to track local water quality trends by river segment.
By analyzing these trends, we are able to: