Smart CSO Control Plans

Many of New Jersey’s oldest cities still rely on combined sewer systems in which stormwater runoff from city streets feeds into sewer lines along with sewage from homes. In dry weather it’s pumped to a sewer treatment plant where it is then treated. Some of these systems are more than 100 years old.

During heavy rainfalls, the volume of stormwater in the combined systems can overwhelm the capacity of the treatment plant. When that happens, combined sewage and stormwater overflows into local waterways and can back up into streets, public spaces such as parks, and even residential basements. 

Jersey Water Works’ initial efforts involved working with communities and utilities that have combined sewer systems to help them identify and implement an appropriate and optimal combination of strategies to reduce sewer overflows. In 2015, the first round of five-year CSO permits were issued by the NJDEP, which required the operators of combined sewer systems to develop a Long Term Control Plan (LTCP) that describes how they intend to reduce overflows. Since then—until the submission of draft LTCPs in 2020—the Jersey Water Works CSO Committee continued the collaborative’s initial efforts by participating in the public input process, assisting communities in submitting comments on the drafts, and submitting its own comments. As the operators begin implementation of the finalized plans and the NJDEP crafts the next five-year permits, the CSO Committee will continue to make recommendations that support cost-effective approaches, affordable options, community benefits, and a balance of green and gray projects.