Continuous water quality monitor that is deployed off a bridge in Westerly RI, just upstream of the 01118500 gage.
Water Quality Sampling and Monitoring of the Pawcatuck River Watershed
Completed
By New England Water Science Center
July 9, 2019
The Pawcatuck River and the Pawcatuck River Estuary and Little Narragansett Bay form part of the boundary between the States of Connecticut and Rhode Island. Both states have identified water quality impairments within these waters related to nutrients (insufficient oxygen) and bacteria. Studies of the eutrophication potential of Long Island Sound embayments have identified that the Pawcatuck River Estuary has the highest total load of nitrogen per embayment area of all embayments studied throughout Long Island Sound.
Sources/Usage: Public Domain. View Media Details
From May 2019 to May 2020, USGS will collect water quality samples for the Connecticut Department of Energy and Environmental Protection (CTDEEP) and the Rhode Island Department of Environmental Management (RIDEM) in the freshwater Pawcatuck River. The data collected through this project is intended to be used by the states of CT and RI to support a HSPF watershed loading model for the Pawcatuck River watershed to quantify loads to the Pawcatuck River Estuary. It is planned that future steps by CTDEEP and RIDEM will use this loading information in an estuarine water quality model to determine target nitrogen loads. The data will be used to inform development of management activities to address nutrient-related water quality impacts.
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.
| Analyte | Lab | Analysis method | Parameter Codes | NWQL Minimum Reporting Limit |
| Ammonia | NWQL | Method ID: I-2522-90 (Fishman, 1993) | 608 | 0.01 mg/L |
| Ammonia + Organic Nitrogen (Whole) | NWQL | Method ID: I-4515-91 (Patton and Truitt, 2000) | 625 | 0.07 mg/L |
| Ammonia + Organic Nitrogen (Dissolved) | NWQL | Method ID: I-2515-91 (Patton and Truitt, 2000) | 623 | 0.07 mg/L |
| Nitrite | NWQL | Method ID: I-2540-90, I-2542-89 (Fishman, 1993) | 613 | 0.001 mg/L |
| Nitrite + Nitrate | NWQL | Method ID: I-2547-11 (Patton and Kryskalla, 2011) | 631 | 0.04 mg/L |
| Phosphorus ( Dissolved ) | NWQL | Method ID: 365.1 (EPA 365.1, 1993) | 666 | 0.003 mg/L |
| Orthophosphate | NWQL | Method ID: I-2601-90, I-2606-89 (Fishman, 1993) | 671 | 0.004 mg/L |
| Phosphorus (Whole) | NWQL | Method ID: 365.1 (EPA 365.1, 1993) | 665 | 0.004 mg/L |
| Total nitrogen (NH3+NO2+NO3+Organic) | NWQL | Method ID: I-2650-03 (Patton and Kryskalla, 2003) | 62854 | 0.05 mg/L |
| Total Particulate Nitrogen (TPN) | NWQL | Method ID: 365.1 (Zimmerman and others, 1997) | 49570 | 0.03 mg/L |
| Chlorophyll-a, phytoplankton | NWQL | Method ID: 445.0 (Arar and Collins, 1997) | 70953 | 0.1 ug/L |
| Pheophytin, phytoplankton | NWQL | Method ID: 445.0 (Arar and Collins, 1997) | 62360 | 0.1 ug/L |
| Total Suspended Solids, Residue on Evaporation (ROE) | NWQL | Method ID: I-3765-85 (Fishman and Friedman, 1989). Page 443 | 530 | 15 mg/L |
| Chlorophyll | Field | Bennett and others (2014), YSI EXO user Manual (appendix 10) | N/A | N/A |
| Dissolved Oxygen | Field | Wagner and others (2006) | 300 | N/A |
| Specific conductance | Field | Wagner and others (2006) | 95 | N/A |
| pH | Field | Wagner and others (2006) | 400 | N/A |
| Water Temperature ℃ | Field | Wagner and others (2006) | 10 | N/A |
| Turbidity | Field | Wagner and others (2006) | 63680 | N/A |
Continuous water quality monitor
Continuous water quality monitor that is deployed off a bridge in Westerly RI, just upstream of the 01118500 gage.
The Pawcatuck River and the Pawcatuck River Estuary and Little Narragansett Bay form part of the boundary between the States of Connecticut and Rhode Island. Both states have identified water quality impairments within these waters related to nutrients (insufficient oxygen) and bacteria. Studies of the eutrophication potential of Long Island Sound embayments have identified that the Pawcatuck River Estuary has the highest total load of nitrogen per embayment area of all embayments studied throughout Long Island Sound.
Sources/Usage: Public Domain. View Media Details
From May 2019 to May 2020, USGS will collect water quality samples for the Connecticut Department of Energy and Environmental Protection (CTDEEP) and the Rhode Island Department of Environmental Management (RIDEM) in the freshwater Pawcatuck River. The data collected through this project is intended to be used by the states of CT and RI to support a HSPF watershed loading model for the Pawcatuck River watershed to quantify loads to the Pawcatuck River Estuary. It is planned that future steps by CTDEEP and RIDEM will use this loading information in an estuarine water quality model to determine target nitrogen loads. The data will be used to inform development of management activities to address nutrient-related water quality impacts.
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.
| Analyte | Lab | Analysis method | Parameter Codes | NWQL Minimum Reporting Limit |
| Ammonia | NWQL | Method ID: I-2522-90 (Fishman, 1993) | 608 | 0.01 mg/L |
| Ammonia + Organic Nitrogen (Whole) | NWQL | Method ID: I-4515-91 (Patton and Truitt, 2000) | 625 | 0.07 mg/L |
| Ammonia + Organic Nitrogen (Dissolved) | NWQL | Method ID: I-2515-91 (Patton and Truitt, 2000) | 623 | 0.07 mg/L |
| Nitrite | NWQL | Method ID: I-2540-90, I-2542-89 (Fishman, 1993) | 613 | 0.001 mg/L |
| Nitrite + Nitrate | NWQL | Method ID: I-2547-11 (Patton and Kryskalla, 2011) | 631 | 0.04 mg/L |
| Phosphorus ( Dissolved ) | NWQL | Method ID: 365.1 (EPA 365.1, 1993) | 666 | 0.003 mg/L |
| Orthophosphate | NWQL | Method ID: I-2601-90, I-2606-89 (Fishman, 1993) | 671 | 0.004 mg/L |
| Phosphorus (Whole) | NWQL | Method ID: 365.1 (EPA 365.1, 1993) | 665 | 0.004 mg/L |
| Total nitrogen (NH3+NO2+NO3+Organic) | NWQL | Method ID: I-2650-03 (Patton and Kryskalla, 2003) | 62854 | 0.05 mg/L |
| Total Particulate Nitrogen (TPN) | NWQL | Method ID: 365.1 (Zimmerman and others, 1997) | 49570 | 0.03 mg/L |
| Chlorophyll-a, phytoplankton | NWQL | Method ID: 445.0 (Arar and Collins, 1997) | 70953 | 0.1 ug/L |
| Pheophytin, phytoplankton | NWQL | Method ID: 445.0 (Arar and Collins, 1997) | 62360 | 0.1 ug/L |
| Total Suspended Solids, Residue on Evaporation (ROE) | NWQL | Method ID: I-3765-85 (Fishman and Friedman, 1989). Page 443 | 530 | 15 mg/L |
| Chlorophyll | Field | Bennett and others (2014), YSI EXO user Manual (appendix 10) | N/A | N/A |
| Dissolved Oxygen | Field | Wagner and others (2006) | 300 | N/A |
| Specific conductance | Field | Wagner and others (2006) | 95 | N/A |
| pH | Field | Wagner and others (2006) | 400 | N/A |
| Water Temperature ℃ | Field | Wagner and others (2006) | 10 | N/A |
| Turbidity | Field | Wagner and others (2006) | 63680 | N/A |