Municipal System Overview and Description


Sewer System Expansion Program
The WSA continues its aggressive sewer expansion program intended to mitigate on-lot sewage disposal systems as a source of pathogens to Greenwich Bay and Narragansett Bay.

Sewer expansion projects that are presently under construction are:

  • Old Buttonwoods
  • Warwick Cove IIB
  • Capron Farm

By the year 2013, the WSA plans to initiate construct the following sewer extensions. Sewering of these areas is contingent upon the availability of local and state funds.

  • Strawberry Road Phase II
  • Bayside Phases I, II, III and IV
  • Governor Francis Farm Phases II and III

The WSA also plans to initiate the design phase of several other projects that include:

  • Northwest Gorton Pond
  • Greenwood East
  • Sherwood Park
  • Sandy Lane/Cedar Swamp

The areas identified above have all been included in the City’s approved Facilities Plan. Information regarding their specific location and the number of residential properties to be served can be obtained from the WSA.

Total Maximum Daily Load Analysis for Greenwich Bay Waters
The RIDEM Office of Water Resources, in December 2005, completed a Total Maximum Daily Load (TMDL) plan for Greenwich Bay. The TMDL plan addresses fecal coliform impairments to Greenwich Bay, Brush Neck Cove, Buttonwoods Cove, Warwick Cove, Hardig Brook, Tuscatucket Brook, two additional Coves, and seven tributaries within the Greenwich Bay watershed, located in the City of Warwick and the Towns of East Greenwich and West Warwick, Rhode Island. These waters are listed on Rhode Island’s 2002 303(d) List of Impaired Waters as Group 1 waters. Two of the Greenwich Bay coves and the seven other tributaries included in this TMDL were found to violate standards during the course of the project and are addressed in the TMDL plan. These waters do not support their designated uses. Designated uses for these waters include primary and secondary contact recreation, fish and wildlife habitat, and for those waters classified as SA, shellfish harvesting.

The TMDL plan aims to restore Greenwich Bay waters by identifying necessary pollutant reductions, locating pollution sources, and outlining an implementation strategy to abate fecal coliform sources such that water quality standards can ultimately be attained during all weather conditions.

With a few exceptions, bacteria impairments in the Greenwich Bay watershed arise directly following wet weather events. In dry weather, all stations in Greenwich Bay and the coves meet the geometric mean criterion, while five of the stations exceed the 90th percentile criterion for the shellfish use. Following rain events, only one station in Greenwich Bay meets both parts of the Class SA water quality standard. The Greenwich Bay coves exhibit the highest bacteria concentrations, with Apponaug Cove and Brush Neck Cove requiring the largest percent reductions for the entire bay.

The Greenwich Bay tributaries reflect the same water quality trends as Greenwich Bay. Water quality is generally good in dry weather and exceeds standards in wet weather. Required percent reductions in the tributaries range from no reductions at some stations along the Maskerchugg River to a 100 percent reduction required from Southern Creek in Brush Neck Cove. The largest bacteria sources to Greenwich Bay are found in Apponaug Cove (Hardig Brook) and Brush Neck Cove.

Recommended implementation activities focus on storm water and wastewater management. Ongoing efforts to ensure adequate treatment of wastewater through the planned sewer extensions, and the proper operation and maintenance of septic systems should continue. Achieving water quality standards will also require that both the amount of storm water and the bacteria concentrations in that storm water reaching Greenwich Bay are reduced. To reduce runoff volumes and treat storm water, use of infiltration basins or similar structures is recommended. A targeted approach to construction of storm water retrofit best management practices (BMPs) at state and locally owned storm water outfalls is recommended. Priority areas for BMP construction within the City of Warwick are Apponaug Cove and Brush Neck Cove, for the Town of East Greenwich, Greenwich Cove, and for the Town of West Warwick, the Hardig Brook headwaters. This TMDL also recommends pollution prevention efforts to discourage residents from feeding birds, encourage residents to pick up after their pets, and ensure that boats comply with the No Discharge requirements of Rhode Island marine waters.

Rate Structure
There are two classes of users that contribute to City sewer system: Residential and Commercial/Industrial. Residential users are billed a Service Charge of $56.78 per unit and a Consumption Fee based on 85 percent of water usage at $23.89 per 1,000 cubic feet. Commercial/Industrial users are billed a Service Charge of $56.78 per unit and a Consumption Fee based on 100 percent of water usage at $31.69 per 1,000 cubic feet.

Where sewers are available, residences are charged an assessment of $82.00 per foot of frontage. For large lots (1 or more acres) the assessment is based on a complicated formula to account for development potential. The assessment is payable over 20 years and the assessment charge is applied whether or not the property is connected. As discussed above, in response to growing concerns about the environmental impact of on-site septic systems leaching pollutants into Greenwich Bay, the Warwick Sewer Authority has implemented a mandatory connection program.

The WWTF also accepts septage from licensed haulers. The fee for disposing of septage has been set at $47.00 per 1000 gallons. Septage is accepted only from Warwick residents, and each load is monitored for compliance with WSA standards to prevent any toxicity to the biological processes employed at the treatment facility. The WSA limits the volume of septage received on a given day to 25,000 gallons. Over 2.7 million gallons of septage was accepted and treated in 2005. With the implementation of mandatory sewer connection program, we would expect to see a gradual decline in the volume of septage being treated on a daily basis in Warwick.