SPRINGFIELD WATER AND SEWER COMMISSION
REMEDIATION PLAN FOR COMBINED SEWER OVERFLOWS 

What are Combined Sewer Overflows (CSOs)? 

Many communities across the country have older wastewater collection systems called “combined sewer systems.”  These systems are designed to collect sanitary sewage from homes and businesses in the same pipes used to collect stormwater from rainfall and snowmelt.

During dry weather, when only sanitary sewage is entering the pipes, the combined sewer system can contain all of the flow and convey it to the Springfield Regional Wastewater Treatment Facility where it is treated before the clean water is discharged to the Connecticut River.

In wet weather, the addition of stormwater combined with sanitary sewage in the pipes fills the sewer system.  To prevent flow from backing up into basements, or surcharging onto streets, the combined sewers were designed with wet weather overflow structures.  These structures divert a portion of the combined, and very diluted, sanitary sewage and stormwater flow into local waterbodies through outfall pipes.  This is called a combined sewer overflow, or “CSO.”

Where do CSOs discharge in Springfield? 

There are potentially active CSO’s that can discharge from locations along three rivers in Springfield. 

 CSO outfalls do not discharge every time it rains – it depends on the size of the drainage area, the amount of rainfall, and the location and intensity of the storm.  Some outfalls may only discharge a few times per year, while others may discharge more frequently.  The locations of CSO outfalls in Springfield are shown by the red dots on the map below.  Other communities along the rivers also have CSO’s.

Why could CSOs be a problem? 

CSO discharges are made up of a mixture of sanitary sewage, business wastewater, stormwater, and potentially many different types and amounts of pollutants.  Typically the pollutants of concern are fecal coliform bacteria and floatable materials.  CSOs can affect water quality for several days after it rains, if the outfalls continue to overflow, as can be the case for very large storms.  If CSOs exceed water quality standards, sensitive activities such as fishing and boating can be impacted.  CSO discharges could potentially create public health impacts, especially if CSO outfalls are located near outdoor recreational areas.   

Individuals should avoid contact with river water for several days after periods of heavy rainfall to prevent potential adverse health effects from CSOs.  For additional information related to CSOs and potential impacts on recreational waters go to www.epa.gov.  

What are we doing about CSO’s? 

The Springfield Water and Sewer Commission continues to work with the U.S. Environmental Protection Agency (EPA) and MA Department of Environmental Protection (DEP) to schedule CSO projects that will reduce pollutants flowing into the Mill, Chicopee, and Connecticut Rivers.  

Mill River 

The Mill River $5.7 million CSO remediation project was completed in December 2003.  The improvements have reduced the CSO pollution entering the Mill River to one or less overflows in a typical rain year.  

Watershops Pond 

As an outreach effort of the CSO remediation project, a committee of Water and Sewer Commission, City of Springfield, and Community representatives was established to develop solutions and establish best management practices throughout the Watershops Pond watershed.  The Commission budgeted $1.2 million for the design and construction of restoration projects for the Pond.  The design phase is underway and the Commission and Springfield Department of Public Works have completed installation of many new storm drain catch basins to prevent street run-off from entering the Pond. 

Chicopee and Connecticut Rivers 

The Springfield Water and Sewer Commission, EPA, DEP, and the cities of Chicopee and Holyoke are currently working together to develop a regional receiving water quality model for the Chicopee and Connecticut Rivers.  The information collected will aid with assessing the water quality benefits associated with implementing CSO controls.  The regional water quality model will help the communities understand the sources of existing pollution flowing into the rivers.  Additionally, the model will help to prioritize CSO control measures from an overall watershed perspective, to be implemented by the Commission, Chicopee, and Holyoke. 

If you have questions or comments related to the CSO remediation plan, please contact: 

Kathy Pedersen – Public Communications Director
Springfield Water and Sewer Commission
(413) 787-6256  ext. 111