Want to learn more about the CSO public notification issue?

Combined Sewage Overflow, or CSO for short, is the technical term for an event that should concern you if you use the Merrimack River for recreational purposes.

Wastewater treatment plants along the Merrimack are allowed to dump their untreated sewage into the river whenever they are overwhelmed by the volume of material entering the plant. This often happens when it rains — most sewer plants receive both the waste generated by homes and businesses, and the rain runoff that goes into storm drains. It often results in millions of gallons of untreated wastewater being dumped into the Merrimack in a short period of time.

In the long term, the EPA wants to dramatically decrease the incidences of CSOs. In the short term, these CSO events will continue to occur on a regular basis, and so we must deal with their consequences. One key consequence is public notification. Under current Massachusetts law, sewer plants are not required to notify the public when the dumpings occur, nor are they required to inform the public about how much sewage has been released. And since they aren’t required by law to notify the general public, they don’t.

This is an important issue for people who recreate on the Merrimack River — the lower Merrimack in particular, from Lowell to Newburyport. Every year thousands of people come in direct contact with the river’s water when they go boating, fishing, swimming or wading. And there are hundreds more who live on their boats during the summer, particularly in Newburyport. We think that people have a right to know when these CSO events occur so that they can assess the potential risk of coming into contact with sewage-contaminated water.

State lawmakers are considering two bills that would do the following:

Require sewage treatment plants to install meters that will measure how much sewage overflows into the river.

Report incidences of sewage overflows within an hour of the occurrence.  This information must be publicly disseminated, and the state DEP must create a website where data is posted in real time. The DEP will also be required to collect data and release an annual report on CSOs.

Mark all sewage outflow pipes so boaters and river users know where they are.

Here’s a look at the actual bills:



The Merrimack River Watershed Council has been contacting state senators and representatives from throughout the Merrimack Valley and asking for their support on this issue. We’ve also been in contact with local officials in our Merrimack Valley cities and towns. We are happy to report that our efforts have resulted in several lawmakers pledging to support these bills.

The Joint Committee on Environment, Natural Resources and Agriculture will hold a hearing on Nov. 29 at 11 a.m. in the Statehouse on these bills. The MRWC will be there to fight for them. We hope you can join us! Please consider attending this important meeting so your voice can be heard.