Water Quality Sampling and Monitoring of the Pawcatuck

Estuary and WatershedKaitlin Laabs and Theresa Armijo

A Cooperative Multi-Agency Effort

Pawcatuck Estuary ProjectJuly 2018 - September 2018

Characterize conditions in the estuary by:

• Deployed instrumentation at two sites on the Pawcatuck River Estuary

• Continuously measured dissolved oxygen and chlorophyll-a (among other parameters)

• Collected samples for nutrient analyses at locations where instrumentation were deployed

Donahue Park - 01118502

(Pawcatuck River South of Route 1 at Pawcatuck, CT)

Green Haven Marina – 01118520

(Pawcatuck River near Pawcatuck, CT)

Donahue Park (01118502) September 12, 2018

Near-surface dissolved oxygen timeseries

Donahue Park(top monitor)

Specific Conductance (uS/cm)

Dissolved Oxygen (mg/L)

Green Haven Marina (top monitor)

Dissolved Oxygen (mg/L)

Specific Conductance (uS/cm)

Next Steps:

• Need for more data to develop nutrient loading models

• Help determine target nutrient loads for Pawcatuck River Estuary

• Address water quality impacts of nutrient loading

Water Quality Sampling andMonitoring of the PawcatuckWatershed

Water Quality Sampling and Monitoring of the Pawcatuck Watershed is supported by the Southeast New England Program (SNEP) Watershed Grants. SNEP Watershed Grants are funded by the U.S. Environmental Protection Agency (EPA) through a collaboration with Restore America’s Estuaries (RAE). For more on SNEP Watershed Grants, see www.snepgrants.org

http://www.snepgrants.org/

Project Objectives

• Establish a monitoring network to collect samples from fourteen locations in the Pawcatuck River watershed for analysis of nutrients and related parameters as well as stream discharge.

• Collect continuous water quality data at the end of the non-tidal portion of the Pawcatuck River watershed.

Site Locations

Station number Station Name

01117350 CHIPUXET RIVER AT WEST KINGSTON, RI

01117351White Horn Brk at Ministerial Rd near West Kindgston, RI

01117420USQUEPAUG RIVER NEAR USQUEPAUG, RI

01117455Pawcatuck River at Sherman Ave. at Kenyon, RI

01117471BEAVER River Shannock Hill RD, NEAR SHANNOCK, RI

01118009 WOOD River NEAR Alton, RI

01118030Pawcatuck River at Alton-Bradford Road at Bradford, RI

01118055TOMAQUAG BROOK, AT RT. 216, AT BRADFORD, RI

01118100PAWCATUCK River near South Hopkinton, RI

01118356Ashaway River at Extension 184 near Ashaway, RI

01118360 ASHAWAY RIVER AT ASHAWAY, RI

01118400SHUNOCK River NEAR NORTH STONINGTON, CT

01118500 PAWCATUCK River at WESTERLY, RI

412647071373701 Factory Effluent

Discharge Measurements

Discrete Water Quality Sampling

Discrete Water Quality Data Collected

Laboratory Analyte

Ammonia (mg/L)

Ammonia + Organic Nitrogen (Whole and Dissolved) (mg/L)

Nitrite (mg/L)

Nitrite + Nitrate (mg/L)

Phosphorus (Whole and Dissolved) (mg/L)

Phosphate, Orthophosphate (mg/L)

Total nitrogen (Calculated) (mg/L)

Total Particulate Nitrogen and Phosphorus (mg/L)

Chlorophyll-a, phytoplankton (Westerly Only) (ug/L)

Pheophytin, phytoplankton (Westerly Only) (ug/L)

Total Suspended Solids (mg/L)

Field Parameters

Dissolved Oxygen (mg/L)

Specific Conductance (μS/cm)

pH

Water Temperature (°C)

Air Temperature (°C)

Factory Effluent

Continuous Water Quality Monitoring

Pawcatuck River at Westerly RI (01118500)

• Water Temperature (°C)

• pH

• Dissolved Oxygen (mg/L)

• Specific Conductance (µS/cm)

• Turbidity (FNU)

• Chlorophyll (mg/L and RFU)

Continuous vs Discrete Chlorophyll Data

pH vs Dissolved Oxygen

Dissolved Oxygen % Saturation

Next Phases....

Water Quality Monitoring of the Upper Pawcatuck River Estuary

Objective: Collect continuous data for the following physical-chemical parameters: water temperature, specific conductance, salinity and dissolved oxygen, at 2 sites of interest during the winter and spring of 2020 period (5 months January through May).

Questions?

klaabs@usgs.govtraci.iott@ct.gov