Water Quality Monitoring

Monitoring Group
Monitoring Group

Among the goals and objectives of the Niantic River Watershed Protection Plan (NRWPP), is to improve water quality and biological monitoring for the Niantic River and its tributaries.  This includes the establishment of a comprehensive long-term water quality monitoring program for the Niantic River Watershed.

The Niantic River Watershed Committee Monitoring Subcommittee has an ongoing commitment to compiling current and historical water quality data and biological surveys pertaining to the Niantic River.   Evaluation  of this data may reveal long-term water quality changes and trends in the Niantic River.  To view a summary of data collection and water quality studies that have been conducted in the Niantic River and watershed, please click here.

 NRWC Stream Water Quality Monitoring

In spring of 2012, the Monitoring Subcommittee began a water quality monitoring program in Latimer Brook and Cranberry Meadow Brook in Montville and East Lyme. Once a month, volunteers collect water quality data including stream temperature, dissolved oxygen, pH, conductivity and nitrogen (as nitrate-nitrogen).  In 2014, the water quality monitoring program was expanded to include sampling sites on Oil Mill Brook and Stony Brook in Waterford. This data provides information on baseline water quality conditions in the streams. It allows us to identify and evaluate seasonal and annual variations in water chemistry characteristics. The Niantic River Watershed Committee and watershed municipalities use this data to identify areas where water quality is less than optimal and water quality improvements can be made. 

Water quality monitoring volunteers collect a water sample for analysis.
Water quality monitoring volunteers collect a water sample for analysis.

In March of 2017, NRWC completed five years of sampling in watershed streams. After evaluating the water quality data, the Monitoring Subcommittee decided to begin event-based sampling to document how rain events affect nitrogen levels in stream water.  A summary of  the water quality data collected from April 2012 to March 2017 can be viewed here.  

Please note that this data is provisional.

 

For a summary of 2013-2014 water quality data, click here.

For a summary of 2014-2015 water quality data, click here.

For a summary of 2015-2016 water quality data, click here (coming soon!).

For a summary of 2016-2017 water quality data, click here (coming soon!).

2017-2018 event-based water quality data will be posted in spring 2019.

River Bio-assessment by Volunteers (RBV)

RBV sample from Stony Brook in Waterford.
RBV sample from Stony Brook in Waterford.

RBV is an aquatic macro-invertebrate assessment developed by CT DEEP to assess aquatic habitat. This assessment uses the presence or absence of pollutant-sensitive riffle-dwelling aquatic insects to estimate the relative health of a stream. The presence of pollution sensitive insects such as stone flies, mayflies and caddis flies generally indicates that water quality in a stream is very good.

Riffles in Latimer Brook in East Lyme.
Riffles in Latimer Brook in East Lyme.

RBV is conducted  in the fall, in riffle sections of fast-flowing headwater streams.  Riffles are areas within a stream where the streambed rises to intercept the water surface, creating highly oxygenated environments where many aquatic insects can be found. RBV volunteers are required to complete an annual training (or refresher for return volunteers). Once trained, volunteers are assigned a stream to sample. NRWC has sampled a number of sites for several successive years to create a baseline and observe any changes in insect presence that might indicate changes in water quality.

For more information regarding macroinvertebrate monitoring  and to see the results of the RBV surveys, visit the CT DEEP River Bio-assessment by Volunteers (RBV) web page.

Visit this RBV Story Board created by  CT DEEP  to see the results of RBV sampling in the Niantic River Watershed (click on the Southeast Coast tab) and throughout Connecticut.

Stream Temperature Monitoring

NRWC has conducted stream temperature monitoring in Latimer Brook, Cranberry Meadow Brook and an unnamed tributary to Cranberry Meadow Brook to document changes in water temperature due to stormwater runoff. Cranberry Meadow Brook and Latimer Brook are both considered cold water streams (average summer temperature less than 72° F) and have been documented to support native brook trout. Stream temperature monitoring by NRWC has indicated that although Cranberry Meadow Brook maintains cooler water temperatures during the hot summer months suitable to support cold water fish species, Latimer Brook, which was formerly known as a good trout fishing stream, has warmed up and no longer supports  cold water fish species.

Brook Trout (Salvelinus fontinalis)
Brook Trout (Salvelinus fontinalis)

Stream Corridor Assessments

The Niantic River Watershed Committee has conducted stream corridor assessments along select sections of Latimer Brook in East Lyme. These assessments identify and evaluate landscape conditions and infrastructure such as stormwater outfalls that might impact stream habitat and water quality. NRWC uses a protocol developed by the USDA Natural Resource Conservation Service (NRCS) called Stream Walk. This assessment documents conditions such as nearby land-use, the presence or absence and relative abundance of riparian vegetation, the presence of stream conditions such as excessive plant growth or algae, cloudy or murky water, odors, stream bank erosion, and trash or debris, that could indicate or contribute to poor water quality conditions. The watershed committee uses this information to identify areas where stormwater management projects or community outreach can be conducted to improve water quality conditions.

Stream Walk volunteers assess a stormwater outfall to Latimer Brook.
Stream Walk volunteers assess a stormwater outfall to Latimer Brook.

 

If you would like to become a water quality monitoring volunteer, contact Watershed Coordinator Judy Rondeau at judy.rondeau@comcast.net or 860-774-9600, ext. 13, for information on volunteer monitoring opportunities and training dates.


Water Quality Monitoring by Other Organizations/Agencies

US Geological Survey

In 2011, the US Geological Service (USGS)  completed a three year water quality monitoring project on several tributaries to the Niantic River, including Latimer Brook and Oil Mill Brook. The results of the study can be found in the project report, Nutrient Concentrations and Loads and Escherichia coli Densities in Tributaries of the Niantic River Estuary, Southeastern Connecticut, 2005 and 2008-2011

USGS  also conducted a study on the effects of the sewering of Pine Grove on nitrogen load reductions to the Niantic River from 2005 to 2011. Click here for more information on this study. Click here for the final report on this study, USGS Scientific Investigations Report 2015-5011, Evaluation of the Effects of Sewering on Nitrogen Loads to the Niantic River, Southeastern Connecticut, 2005–11. The Town of East Lyme is moving forward with a study of the feasibility of installing sewers in Saunders Point, a decision based in part on the results of the Pine Grove groundwater study .

Click  here to link to Real-Time Data for Latimer Brook.

Millstone Environmental Lab

 The Millstone Environmental Lab collects water quality data from the Niantic River and Niantic Bay throughout the year.  Collected data includes water quality parameters such as temperature, dissolved oxygen, salinity, dissolved organic and inorganic nitrogen, and macro-algae and eelgrass sampling. MEL also collects water quality data at NRWC’s lowermost Latimer Brook site, allowing us to provide a check on our sampling results.

 University of Connecticut

untitledResearchers at the University of Connecticut have conducted rigorous investigations in the Niantic River and Bay. Chief among these are several embayment studies conducted by Dr. Jamie Vaudrey, an Assistant Research Professor with the Department of Marine Sciences. Dr. Vaudrey’s research can be  viewed at http://vaudrey.lab.uconn.edu/.

CFE/Save the Sound Unified Water Study

Save the River-Save the Hills has been participating in the Unified Water Study and collects water quality data  from the Niantic Rive. The Unified Water Study was launched in 2017. The goal was to assist  groups conducting water quality monitoring throughout Long Island Sound to have a consistent protocol so collected data would be comparable. Local monitoring groups receive support from Save the Sound, the study’s Science Advisors, and its funders. They are provided with monitoring equipment, training, Standard Operating Procedures, a custom study design for their monitoring locations, a template Quality Assurance Project Plan (QAPP), and other resources they need to successfully collect high quality monitoring data.

Click here to visit the Unified Water Study website and see data collected by Save the River-Save the Hills from the Niantic River (and around Long Island Sound!).