Nitrogen hearing discusses septic regulations, data quality

Nov 29, 2023

The Massachusetts State Department of Environmental Protection has proposed new limits on nitrogen release — but the regulations are separate from Title V, and will not mandate any septic system upgrades. 

MassDEP held a public hearing on Tuesday, Nov. 28 to explain and hear comments on the draft nitrogen limits for the Wareham River watershed. 

Excessive nitrogen — a chemical released from septic systems, agricultural fertilizer, wastewater treatment plants and more — has caused damage to the waters in Buzzards Bay and in Wareham. 

A set of limits proposed by the Department call for a 37.7% reduction in the amount of nitrogen released into the waters of the Wareham River Estuary System. 

Department representatives began Tuesday's public hearing by clarifying that this process —  which looks at the Total Daily Maximum Load, or TMDL, which establishes the amount of nitrogen that can safely be released into a water body — is unrelated to changes to Massachusetts' Title V regulations. 

The TMDL process is a federal requirement under the Clean Waters Act, which requires state governments to identify damaged water bodies and put limits in place to protect them. 

New Massachusetts state Title V changes, put into place earlier in the year, established strict nitrogen regulations on Cape Cod, including requirements for upgraded septic systems. 

There is currently no timeline in place for expanding Title V regulations to other towns on the South Coast, and doing so would require an extensive public process and regulatory changes, said Department representatives. They added that the TMDL process will not mandate any kind of septic system upgrades. 

During the public comment section of the meeting, several residents took issue with the data used for the TMDL, either with its age or with what it excluded. 

The technical report, which provides the scientific basis for the TMDL, uses information collected from 2005 to 2011, and was written in 2014. 

Michael Bower, who lived at the lower end of the Agwan River, said the 2014 data wouldn't take into account work done since that time. An organization he is a part of, Clean Agawam Mill Pond, has restored approximately one third of the river to a more balanced ecosystem, Bower said.

"You just don't have the data to spend a lot of money in one direction or another with any kind of confidence," Bower said. 

Department representatives said the technical report used a "snapshot" of data to create a model against which present and future changes can be measured. The Department does have more up-to-date data, which was used to determine the water body's impairment and can be included in the town's efforts to address the TMDL, they said. 

Meg Shehan, representing the Community Land and Water Coalition, referenced a report the Coalition created investigating the impacts of sand mining on the environment of Southeastern Massachusetts, and asked that the information from the report be considered in the Department's work. 

Department representatives said they could take the report into the official record. 

Select Board member Alan Slavin said the numbers for Wareham's nitrogen emissions are "distorted" because the nitrogen emissions of towns further north wash into Wareham's waters. 

It's "financially impossible" for Wareham to take care of other towns' problems, Slavin said. "This is one of these things where everybody needs to be involved, everybody needs to contribute financially."

While Slavin did not receive a direct response, representatives talked elsewhere in the meeting about options for regional approaches, including a watershed permit approach with nitrogen loads assigned to each town, rather than just the downstream town. 

The meeting began a 30-day public comment period, to run until Dec. 28. 

Written comments can be submitted via mail to: Massachusetts Department of Environmental Protection, Watershed Planning Program, 8 New Bond Street, Worcester, MA 01606. They can also be submitted by email to, with 'Wareham River TMDL (CN 549.0) comments' included in the subject line.