2026 Haverhill Sewer Main Break
On Friday, June 26, a sewer main break occurred in Haverhill.
As of Monday (June 29), the break was expected to take a minimum of 4 days to repair and possibly longer. Until the break is repaired, the overwhelming majority of Haverhill’s sewage is being discharged directly into the Merrimack River at an estimated rate of 7-10 million gallons a day. The pipe involved was a 50-year old 42” concrete main. As initial evaluation work was done on the site, a second break in the line was discovered several hundred feet up from the first break.
MRWC recommends that people do not engage with the Merrimack River downstream of Haverhill, including Newburyport Harbor, until testing can validate that it is safe to do so. Unsafe conditions will likely extend through the July 4th Weekend.
MRWC is currently testing for bacteria downstream of the break from Haverhill to Plum Island every day beginning Monday June 29 and posting the results below. We are also curating updates from the impacted municipalities at the bottom of this page as they become available to us.
Putting This Event Into Context:
Haverhill has an average of 35 combined sewer overflow (CSO) events in a year. A median Haverhill CSO discharges roughly 60,000 gallons. However, a large Haverhill CSO (top 2%, or roughly once every 2 years) can discharge approximately 10 million gallons. Typical Haverhill CSOs impact an area immediately downstream for roughly 3 days. These typical CSOs do not significantly impact the bacteria levels beyond the Artichoke River in West Newbury.
Post-event Testing
Our Test Sites
The map above shows each of our test sites downstream of Haverhill. We will be testing each of these sites throughout the week and providing information on our test results in the table below. Please note that there is a 24-hour waiting period for each test to allow the bacteria to incubate to a measurable level. The most recent result in the table below will always be from at least 24 hours ago.
Our Test Results
Results in the table below are for bacteria only. A reading of ‘safe’ indicates a fecal coliform level below the recreational limit of either 235 colony-forming units per 100 milliliters for E. coli or 104 colony-forming units per 100 milliliters for Enterococcus.
Test results take 24 hours to incubate so the results in the table below should not be interperted as current information. Defer to public health officials when making the decision to recreate in the river.
| 6/29/2026 | 6/30/2026 | 7/1/2026, Morning | 7/1/2026, Evening | 7/2/2026 | 7/3/2026 | 7/4/2026 | 7/5/2026 | 7/6/2026 | 7/7/2026 | 7/8/2026 | 7/9/2026 | 7/10/2026 | |
| Route 113 Bridge | Safe | 11 – 12x limit | 15 – 16x limit | Safe | Safe | Safe | Safe | Safe | Safe | Safe | Safe | Safe | Safe |
| Ferry Park | >40x limit | 26 – 27x limit | 5 – 6x limit | 4 – 5x limit | Safe | 3 – 4x limit | 1 – 2x limit | 2 – 3x limit | Safe | 1 – 2x limit | 1 – 2x limit | Safe | 3 – 4x limit |
| Deer Island | Safe | Safe | 1 – 2x limit | 4 – 5x limit | 2 – 3x limit | 1 – 2x limit | 1 – 2x limit | Safe | Safe | Safe | Safe | Safe | Safe |
| Route 1 Bridge | 4 – 5x limit | 4 – 5x limit | 1 – 2x limit | 2 – 3x limit | 6 – 7x limit | 1 – 2x limit | 1 – 2x limit | 1 – 2x limit | Safe | Safe | Safe | Safe | Safe |
| Newburyport Harbor Master | 1 – 2x limit | 5 – 6x limit | Safe | 2 – 3x limit | 7 – 8x limit | 1 – 2x limit | Safe | Safe | Safe | Safe | Safe | Safe | Safe |
| Salisbury Beach River Side | Safe | 3 – 4x limit | 2 – 3x limit | 2 – 3x limit | Safe | 1 – 2x limit | 5 – 6x limit | 2 – 3x limit | 4 – 5x limit | 1 – 2x limit | 1 – 2x limit | Safe | Safe |
| Plum Island Light | Safe | Safe | 1 – 2x limit | 2 – 3x limit | Safe | 1 – 2x limit | 1 – 2x limit | 4 – 5x limit | 6 – 7x limit | 1 – 2x limit | 1 – 2x limit | 1 – 2x limit | Safe |
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Municipal and State Response
What is your town or city saying about the impact of this event?
Keep posted for the most recent updates from each municipality, including official recreation recommendations.
A response from Massachusetts Department of Conservation and Recreation (DCR) is also included.
Haverhill
“As of 10:30 a.m. on July 1, emergency bypass pumping contractors successfully completed installation of the first 24-inch temporary bypass pipeline. The bypass pumping system is now fully operational, and wastewater flow has been restored from the South Mill Street Pump Station to the Haverhill Wastewater Treatment Plant for treatment. As a result, the sanitary sewer overflow to the Merrimack River ceased at approximately 10:30 a.m.
The temporary bypass system currently provides sufficient capacity to convey Haverhill’s dry weather wastewater flow to the treatment plant. The City continues to work around the clock on a permanent repair to the damaged 42-inch force main while simultaneously constructing a second temporary bypass pipeline. Once completed, the second bypass line will provide sufficient capacity to convey wet weather flows of up to 30 million gallons per day, significantly improving system reliability until the permanent force main repairs are complete.
Excavation and bypass installation crews remain on site and continue to coordinate construction activities, including installation of the second bypass line, preparation for the permanent force main repair, and restoration of the affected area.
The City continues to coordinate closely with the Massachusetts Department of Environmental Protection (MassDEP) and other regulatory partners throughout the response. Although the discharge to the Merrimack River has ceased, residents and recreational users are advised to avoid contact with the river in the vicinity of Haverhill and downstream for at least 48 hours, or until otherwise recommended by public health officials, due to the potential presence of elevated bacteria and other pollutants resulting from the recent sanitary sewer overflow.
The City appreciates the patience and cooperation of residents and downstream communities during this emergency response and will continue to provide updates as necessary.”
Read more from the City of Haverhill here. (7/2/26)
The Merrimack River Watershed Council will post test results from the Route 113 Bridge above as they become available.
Groveland
“The Groveland Board of Health has been notified that the sewer line break that has resulted in a sewage discharge into the Merrimack River upstream of Groveland has been fixed with a bypass line.
As a precaution, residents and visitors are advised to avoid contact with the river, including swimming, wading, and other recreational water activities, for at least 48 hours following the discharge.
The Board of Health will continue to monitor the situation as additional updates become available.“
Read more from the Town of Groveland here. (7/4/2026)
West Newbury
“As of 6:47 AM this morning the SSO is still ongoing. The 24” bypass pipe has been fully installed
and the City of Haverhill is anticipating that it will be operational sometime this morning.”
Check here for updates from the West Newbury Board of Health. (7/1/26)
Merrimac
“The Town of Merrimac and Health Agent Debbie Ketchen advise residents not to swim in the Merrimack River due to an incident in Haverhill that led to a discharge of untreated wastewater into the river.
On Friday, June 26 and Saturday, June 27, the City of Haverhill identified two breaks in sewer mains near its main pumping stations and confirmed that there was an ongoing discharge of untreated wastewater going into the Merrimack River.
As a result of the discharge of untreated wastewater, Health Agent Ketchen strongly urges residents not to swim or allow pets in the Merrimack River.
While the Town of Merrimac has no public access points to the Merrimack River, a number of private residents do.
Several surrounding towns that offer public access points, including Newburyport, Ipswich, and Newbury, have closed their beaches to swimming. These closures will remain in place until regular testing indicates the water is safe to swim in.
Swimming in bacteria-contaminated water poses serious health risks. Exposure can cause gastrointestinal, respiratory, dermatological, eye, and ear symptoms, and in some cases, more serious illnesses. Children, older adults, and people with weakened immune systems are particularly vulnerable.
The Town urges residents to obey all posted signage if they travel to any beaches in the surrounding area.
While this untreated sewage discharge impacts the Merrimack River and downstream points, there is no impact to the town’s potable water sources. Merrimac’s potable water is drawn from wells, and town water customers can remain confident in the quality and safety of the drinking water.”
Amesbury
“The Amesbury Board of Health (BOH) would like to make you aware of a sanitary sewer overflow that occurred in the City of Haverhill on June 26, 2026, impacting downstream communities along the Merrimack River, including Amesbury.
The Amesbury Board of Health is in communication with the City of Haverhill and continues to advise people to avoid contact with the water in the Merrimack River due to the elevated bacteria levels and other contaminants associated with untreated wastewater. Please follow any posted signage.
This warning will remain in effect until further notice.”
Newburyport
“As the public is aware, a major sewer force main failure occurred in the City of Haverhill on June 26, resulting in the discharge of untreated wastewater into the Merrimack River, causing Newburyport to have to close Plum Island beaches in the City, as well as to advise against access to the Merrimack River.
On the morning of Wednesday Jul 1st, we received news from the City of Haverhill that a 24″ bypass line has now been installed and connected to the Haverhill treatment plant. This bypass line is intended to prevent further discharge into the Merrimack River of untreated sewage graywater, which has been ongoing after the sewer force main failure in Haverhill.
We are working with other municipalities and state officials to determine whether this bypass line will have the intended effect and allow for the reopening of Newburyport’s beaches. At the moment, all City of Newburyport beaches remain closed for swimming. Residents and visitors are also advised to continue to avoid contact with Merrimack River water and Plum Island beaches for both humans and pets until further notice from the Newburyport Board of Health. Fishing (including clamming and shellfish harvesting) in the river and along the coast is strongly advised against, as testing points along the river indicate dangerous fecal bacteria levels.”
Read the full update from the City of Newburyport here (7/1/26)
Salisbury
“The State Department of Conservation and Recreation has issued the following precautionary posting for Plum Island and Salisbury Beaches: Swimming at these beaches is not advised at the present time due to potential exposure to bacteria associated with a sanitary sewer overflow in Haverhill, which was caused by the rupture of a force sewer drain.”
Check for updates from the Town of Salisbury here (6/29/2026)
Massachusetts
“Swimming at Salisbury Beach State Reservation Main Beach & North Beach DCR has issued a precautionary posting in response to the recent CSO event in Haverhill affecting the Merrimack River which lets out to the Atlantic Ocean adjacent to Salisbury State Reservation. Swimming is not advised due to potential exposure to bacteria associated with the accidental wastewater release. Please check back for updates.”