The Scituate Reservoir system is the largest inland body of water in Rhode Island and the principal drinking-water supply for more than 60 percent of the State’s population. The system includes the Scituate Reservoir and five tributary reservoirs with a maximum storage capacity of 37 billion gallons. The drainage basin that contributes water to the reservoir extends across 93 square miles in northwestern Rhode Island.
Most of the drainage basin (87 percent) is undeveloped forestland, but the basin also contains residential, commercial, and industrial development, and it is crossed by a major highway. Various contaminants associated with these land uses are a concern, including sodium and chloride from the application of deicing compounds on roads. The Providence Water Supply Board (PWSB), the agency tasked with managing the drainage basin for source-water protection, closely monitors water quality in the tributaries that drain into the basin, through a long-term sampling program and cooperative agreements with the U.S. Geological Survey (USGS) to collect streamflow data and analyze constituent loads of water-quality constituents that might lead to the degradation of reservoir water quality. This cooperative monitoring program provides PWSB resource managers with ongoing information about quality and quantity of water conditions in the basin as well as the rate of loading for constituents of interest to the reservoir.
The USGS started collecting streamflow data in the Scituate Reservoir drainage area in the 1990s.These flow data provided essential information needed to estimate the mass loads of constituents carried by the tributaries into the reservoir at the time of sampling; with data on loads, the relative inputs of constituents to the reservoir from the different tributaries can be compared. In 2009, a cooperative agreement between the PWSB and the USGS added continuous streamflow- and water-quality monitoring at 12 additional monitoring stations on tributaries to the reservoir system. Currently, the USGS operates 16 continuous monitoring stations in the Scituate Reservoir drainage area and collects periodic water-quality samples at each site. The continuous streamflow data have greatly increased the accuracy of the load estimates. Continuous water-quality monitoring data have been used to more precisely calculate loads of sodium and chloride—constituents of concern entering the reservoir. The continuous data also have allowed the PWSB to gain a better understanding of temporal changes in the overall quality and quantity of the source water to the reservoir and provide the PWSB with near real-time information about conditions within the drainage basin.
Knowledge of the temporal trends in the physical properties and constituent concentrations routinely measured in water-quality samples can be used to predict future water-quality problems or recognize improvements. Continued analysis of historic and new concentration and load data, and improvements to the precision of such estimates through investments in the current monitoring network are essential to sustaining the high-quality source of water to Scituate Reservoir and understanding how water quality in the tributaries may be changing over time.
Below are data or web applications associated with this project.
Water-quality data from the Providence Water Supply Board for tributary streams to the Scituate Reservoir, water years 2018-19
Water quality data from the Providence Water Supply Board for tributary streams to the Scituate Reservoir, water year 2016
Below are publications associated with this project.
Streamflow, water quality, and constituent loads and yields, Scituate Reservoir Drainage Area, Rhode Island, Water Year 2017
Streamflow, water quality, and constituent loads and yields, Scituate Reservoir Drainage Area, Rhode Island, Water Year 2016
Streamflow, water quality, and constituent loads and yields, Scituate Reservoir Drainage Area, Rhode Island, water year 2015
Loads and yields of deicing compounds and total phosphorus in the Cambridge drinking-water source area, Massachusetts, water years 2009–15
Streamflow, water quality and constituent loads and yields, Scituate Reservoir drainage area, Rhode Island, water year 2014
Water-quality trends in the Scituate reservoir drainage area, Rhode Island, 1983-2012
Streamflow, water quality, and constituent loads and yields, Scituate Reservoir drainage area, Rhode Island, water year 2013
Streamflow, water quality, and constituent loads and yields, Scituate Reservoir drainage area, Rhode Island, water year 2012
Streamflow, water quality, and constituent loads and yields, Scituate Reservoir drainage area, Rhode Island, water year 2011
Streamflow, water quality, and constituent loads and yields, Scituate Reservoir drainage area, Rhode Island, water year 2010
Streamflow, water quality, and constituent loads and yields, Scituate Reservoir drainage area, Rhode Island, water year 2009
Streamflow, Water Quality, and Constituent Loads and Yields, Scituate Reservoir Drainage Area, Rhode Island, Water Year 2006
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- Overview
The Scituate Reservoir system is the largest inland body of water in Rhode Island and the principal drinking-water supply for more than 60 percent of the State’s population. The system includes the Scituate Reservoir and five tributary reservoirs with a maximum storage capacity of 37 billion gallons. The drainage basin that contributes water to the reservoir extends across 93 square miles in northwestern Rhode Island.
Photograph of U.S. Geological Survey technician collecting an isokinetic equal-width increment water sample at USGS streamgage 01115265, Hemlock Brook at King Road near Foster, Rhode Island. Most of the drainage basin (87 percent) is undeveloped forestland, but the basin also contains residential, commercial, and industrial development, and it is crossed by a major highway. Various contaminants associated with these land uses are a concern, including sodium and chloride from the application of deicing compounds on roads. The Providence Water Supply Board (PWSB), the agency tasked with managing the drainage basin for source-water protection, closely monitors water quality in the tributaries that drain into the basin, through a long-term sampling program and cooperative agreements with the U.S. Geological Survey (USGS) to collect streamflow data and analyze constituent loads of water-quality constituents that might lead to the degradation of reservoir water quality. This cooperative monitoring program provides PWSB resource managers with ongoing information about quality and quantity of water conditions in the basin as well as the rate of loading for constituents of interest to the reservoir.
The USGS started collecting streamflow data in the Scituate Reservoir drainage area in the 1990s.These flow data provided essential information needed to estimate the mass loads of constituents carried by the tributaries into the reservoir at the time of sampling; with data on loads, the relative inputs of constituents to the reservoir from the different tributaries can be compared. In 2009, a cooperative agreement between the PWSB and the USGS added continuous streamflow- and water-quality monitoring at 12 additional monitoring stations on tributaries to the reservoir system. Currently, the USGS operates 16 continuous monitoring stations in the Scituate Reservoir drainage area and collects periodic water-quality samples at each site. The continuous streamflow data have greatly increased the accuracy of the load estimates. Continuous water-quality monitoring data have been used to more precisely calculate loads of sodium and chloride—constituents of concern entering the reservoir. The continuous data also have allowed the PWSB to gain a better understanding of temporal changes in the overall quality and quantity of the source water to the reservoir and provide the PWSB with near real-time information about conditions within the drainage basin.
Knowledge of the temporal trends in the physical properties and constituent concentrations routinely measured in water-quality samples can be used to predict future water-quality problems or recognize improvements. Continued analysis of historic and new concentration and load data, and improvements to the precision of such estimates through investments in the current monitoring network are essential to sustaining the high-quality source of water to Scituate Reservoir and understanding how water quality in the tributaries may be changing over time.
Photograph of U.S. Geological Survey technician measuring water quality properties at USGS streamgage 01115265, Hemlock Brook at King Road near Foster, Rhode Island. Photograph of the sampling system used to collect flow-proportional filtered and nonfiltered composite samples of stormflow at the 01115110, Huntinghouse Brook at Elmdale Road near North Scituate, Rhode Island, streamgage. - Data
Below are data or web applications associated with this project.
Water-quality data from the Providence Water Supply Board for tributary streams to the Scituate Reservoir, water years 2018-19
Water-quality data were collected by the Providence Water Supply Board (PWSB) from tributaries in the Scituate Reservoir drainage area, October 2017 through September 2019 (water years 2018 and 2019). Water-quality samples were collected by the PWSB either monthly or quarterly at fixed stations on 37 tributaries in the Scituate Reservoir drainage area. These data were used to calculate instantaneoWater quality data from the Providence Water Supply Board for tributary streams to the Scituate Reservoir, water year 2016
Water-quality data were collected by the Providence Water Supply Board (PWSB) from tributaries in the Scituate Reservoir drainage area, October 2015 through September 2016 (water year 2016). These data were used to calculate instantaneous loads and yields of constituents in a report by the U.S. Geological Survey. Water-quality samples were collected by the PWSB either monthly or quarterly at fixed - Multimedia
- Publications
Below are publications associated with this project.
Filter Total Items: 23Streamflow, water quality, and constituent loads and yields, Scituate Reservoir Drainage Area, Rhode Island, Water Year 2017
As part of a long-term cooperative program to monitor water quality within the Scituate Reservoir drainage area, the U.S. Geological Survey, in cooperation with the Providence Water Supply Board, collected streamflow and water-quality data at the Scituate Reservoir and tributaries. Streamflow and concentrations of chloride and sodium estimated from records of specific conductance were used to calcStreamflow, water quality, and constituent loads and yields, Scituate Reservoir Drainage Area, Rhode Island, Water Year 2016
As part of a long-term cooperative program to monitor water quality within the Scituate Reservoir watershed, the U.S. Geological Survey in cooperation with the Providence Water Supply Board collected streamflow and water-quality data at the Scituate Reservoir and tributaries. Streamflow and concentrations of chloride and sodium estimated from records of specific conductance were used to calculateStreamflow, water quality, and constituent loads and yields, Scituate Reservoir Drainage Area, Rhode Island, water year 2015
Streamflow and concentrations of sodium and chloride estimated from records of specific conductance were used to calculate loads of sodium and chloride during water year (WY) 2015 (October 1, 2014, through September 30, 2015) for tributaries to the Scituate Reservoir, Rhode Island. Streamflow and water-quality data used in the study were collected by the U.S. Geological Survey and the Providence WLoads and yields of deicing compounds and total phosphorus in the Cambridge drinking-water source area, Massachusetts, water years 2009–15
The source water area for the drinking-water supply of the city of Cambridge, Massachusetts, encompasses major transportation corridors, as well as large areas of light industrial, commercial, and residential land use. Because of the large amount of roadway in the drinking-water source area, the Cambridge water supply is affected by the usage of deicing compounds and by other constituents that areStreamflow, water quality and constituent loads and yields, Scituate Reservoir drainage area, Rhode Island, water year 2014
Streamflow and concentrations of sodium and chloride estimated from records of specific conductance were used to calculate loads of sodium and chloride during water year (WY) 2014 (October 1, 2013, through September 30, 2014) for tributaries to the Scituate Reservoir, Rhode Island. Streamflow and water-quality data used in the study were collected by the U.S. Geological Survey and the Providence WWater-quality trends in the Scituate reservoir drainage area, Rhode Island, 1983-2012
The Scituate Reservoir is the primary source of drinking water for more than 60 percent of the population of Rhode Island. Water-quality and streamflow data collected at 37 surface-water monitoring stations in the Scituate Reservoir drainage area, Rhode Island, from October 2001 through September 2012, water years (WYs) 2002-12, were analyzed to determine water-quality conditions and constituent lStreamflow, water quality, and constituent loads and yields, Scituate Reservoir drainage area, Rhode Island, water year 2013
Streamflow and concentrations of sodium and chloride estimated from records of specific conductance were used to calculate loads of sodium and chloride during water year (WY) 2013 (October 1, 2012, through September 30, 2013) for tributaries to the Scituate Reservoir, Rhode Island. Streamflow and water-quality data used in the study were collected by the U.S. Geological Survey (USGS) or the ProvidStreamflow, water quality, and constituent loads and yields, Scituate Reservoir drainage area, Rhode Island, water year 2012
Streamflow and concentrations of sodium and chloride estimated from records of specific conductance were used to calculate loads of sodium and chloride during water year (WY) 2012 (October 1, 2011, through September 30, 2012), for tributaries to the Scituate Reservoir, Rhode Island. Streamflow and water-quality data used in the study were collected by the U.S. Geological Survey (USGS) or the ProviStreamflow, water quality, and constituent loads and yields, Scituate Reservoir drainage area, Rhode Island, water year 2011
Streamflow and concentrations of sodium and chloride estimated from records of specific conductance were used to calculate loads of sodium and chloride during water year (WY) 2011 (October 1, 2010, to September 30, 2011), for tributaries to the Scituate Reservoir, Rhode Island. Streamflow and water-quality data used in the study were collected by the U.S. Geological Survey (USGS) or the ProvidenceStreamflow, water quality, and constituent loads and yields, Scituate Reservoir drainage area, Rhode Island, water year 2010
Streamflow and water-quality data were collected by the U.S. Geological Survey (USGS) or the Providence Water Supply Board (PWSB), Rhode Island's largest drinking-water supplier. Streamflow was measured or estimated by the USGS following standard methods at 23 streamgages; 14 of these stations were also equipped with instrumentation capable of continuously monitoring specific conductance and waterStreamflow, water quality, and constituent loads and yields, Scituate Reservoir drainage area, Rhode Island, water year 2009
Streamflow and water-quality data were collected by the U.S. Geological Survey (USGS) or the Providence Water Supply Board (PWSB), Rhode Island's largest drinking-water supplier. Streamflow was measured or estimated by the USGS following standard methods at 23 streamgage stations; 13 of these stations were also equipped with instrumentation capable of continuously monitoring specific conductance aStreamflow, Water Quality, and Constituent Loads and Yields, Scituate Reservoir Drainage Area, Rhode Island, Water Year 2006
Streamflow and water-quality data were collected by the U.S. Geological Survey (USGS) or the Providence Water Supply Board, Rhode Island's largest drinking-water supplier. Streamflow was measured or estimated by the USGS following standard methods at 23 streamgage stations; 10 of these stations were also equipped with instrumentation capable of continuously monitoring specific conductance. Streamf - Partners
Below are partners associated with this project.