The Providence and Seekonk Rivers
a map tour

The Providence and Seekonk Rivers are located in Upper Narragansett Bay in Rhode Island.  While called "rivers", they are actually estuaries.  Most of the flow is tidal and they are principally seawater rather than freshwater. (Kester, 133)

 
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The two rivers are affected by two watersheds, the Narragansett Watershed and the Blackstone Watershed.  Each watershed is located in both Massachusetts and Rhode Island.
 
The Narragansett Watershed
For more information on the Narragansett watershed, visit. EPA Surf your Watershed (exit this site)

 
 
The Blackstone Watershed
for more information on the Blackstone  watershed, visit EPA Surf your Watershed (exit this site)

 
Discharges from wastewater treatment facilities into the waters that flow to the Providence and Seekonk come from the north, east and west.  From the north, discharges come from Massachusetts and Rhode Island down the Blackstone River.  These include discharges to the Mumford River, the Mill River, the West River and the Clear River, which flow into the Blackstone.  From the north and west come discharges from the Moshassuck, Woonasquatucket, and the Pawtuxet Rivers.  From the east, facilities in Massachusetts discharge to the Ten Mile River.  There are also facilities that discharge directly into the Providence and Seekonk Rivers. 
The criteria for Dissolved Oxygen in SB and SB1 waters is not less than 5 mg/l at any place or time, except as naturally occurs.   The designation {a} for these waters denotes partial use of classification due to impacts from combined sewer overflows (303d, 25)

 

The 2000 303(d) list identifies impaired waterbodies within the State of Rhode Island, the priority ranking, and scheduled time frame for development of TMDLs. (303d, 4)  Each waterbody is put into one or more of five groups.  The Seekonk River is included in groups 1 and 5.  The Providence River is included in groups 1, 3 and 5.  The relevant group designations are as follows:

Group 1 - (TMDL Underway) - These waters are not meeting Rhode Island Water Quality Standards and TMDL development is currently underway.

Group 3 - (Dissolved Metals Data Needed) - Monitoring data for metals for these waters show violations of criteria however, all data is expressed as total metals. Based on 1997 amendments to Rhode Island’s WQS, metals criteria are now expressed as dissolved. Therefore, it is not known whether these waters have metal violations based on dissolved criteria. Additional sampling is required to make this assessment.

Group 5 - (TMDL or Equivalent Control Action Developed) - A TMDL, or a control action functionally equivalent to a TMDL, has been developed for these waterbodies.  Implementation is underway which will result in attainment of the standards. However, the standards will not be met within the next two years. (303d, 4)

The Seekonk River is included under group 1 for hypoxia, nutrients, and excess algal growth and under group 5 for pathogens.  The Providence River is included under group 1 for hypoxia and nutrients, under group 3 for metals and under group 5 for pathogens.

 

from: Cleaning up PollutedWaters:A Summary of Rhode Island'sTotal Maximum Daily Load Program

RIDEM, Office of Water Resources

The following charts from Kester et al show the salinity of different zones in Narragansett Bay.  The Providence and Seekonk Rivers are zones 1 and 9, respectively. (Kester, 133)

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