Clock to start ticking for Cape towns to reduce nitrogen pollution. Which town is exempt?

On Friday, the state Department of Environmental Protection will turn the proverbial hourglass and begin to measure out the time that most of the Cape has to respond to new regulations calling for enhanced nitrogen removal in watersheds now designated as Nitrogen Sensitive Areas.

One exception is Provincetown, which is exempt from the Cape-focused regulations under the state's Title 5 environmental laws — meaning residents there don't have to worry about meeting a state deadline to upgrade or replace septic systems.

Additionally, the hourglass will flow much more slowly from the get-go for the four towns that are part of the Pleasant Bay watershed — Brewster, Chatham, Harwich and Orleans. That's because there is already a pilot Pleasant Bay Watershed Permit in place, according to the Cape Cod Commission, giving the towns at least 20 years to reduce nitrogen loading in their estuaries and embayments.

So, what's the problem?

At the center of the issue is the nitrogen pollution that's built up over decades as development on the peninsula has advanced, resulting in poor and murky water quality and algae growth that negatively affects the ecosystem, including shellfish that form the basis of an important Cape Cod fishery. Extensive scientific research has shown this is primarily owing to nitrogen outflow from septic systems.

According to the Cape Cod Area Wide Water Quality Management Plan update, persistent water quality problems will have far-reaching impacts, since the Cape's water resources "drive the regional economy."

"The economic impact of doing nothing to restore coastal water quality will be significant, affecting every homeowner in the region," the plan states.

What do the new rules require?

Under the new regulations, towns with impacted watersheds have two years either to give the state a notice of intent to file a watershed permit or to apply for a watershed permit that outlines plans for reducing nitrogen pollution, which could include any combination of sewering, alternative wastewater management systems and septic system upgrades. Once a permit is granted, the towns then have at least 20 years to implement their plans.

Absent a notice of intent or a watershed permit, property owners within watersheds considered Nitrogen Sensitive Areas — which comprise areas of 14 out of 15 of the Cape's towns with watersheds flowing toward Nantucket Sound — will have five years to replace or upgrade septic systems to filter out nitrogen.

MassDEP Deputy Commissioner Gary Moran said the five-year clock would start after the two-year deadline for towns to indicate if they will seek a watershed permit.

Why is Provincetown exempt?

Provincetown is exempt from the new rules because "they are not facing the same problems in terms of nitrogen pollution," Moran said.

He added that the flow of water around the tip of the Cape naturally flushes things out. But on top of that, Provincetown Town Manager Alex Morse pointed out the town has been "a progressive pioneer in addressing nitrogen pollution from wastewater" as the first town on Cape to begin operating a municipal sewer system in 2003.

"Because of this, the town’s waters have significantly lower levels of nitrogen pollution than its neighbors, and DEP has determined that we do not currently have any Nitrogen Sensitive Areas," he said.

DEP’s new rules call for property owners in other towns who do need to go with septic system upgrades or replacements to install the “best available technology” to reduce nitrogen leaching into groundwater. Municipal wastewater treatment facilities like Provincetown’s, Morse said, are already the "best available technology" to reduce nitrogen levels in wastewater effluent, and 50% of the town is currently on the sewer system.

Provincetown is reducing nitrogen discharge on its own.

"Continuing its status as a pioneer in this area, at the Nov. 9, 2022, special town meeting, Provincetown voters overwhelmingly approved the Phase 6 Final Sewer Expansion Plan to serve all remaining properties in town by the end of the decade," he said.

Until all properties are connected to the sewer, the Provincetown Board of Health has taken steps further to reduce nitrogen discharges from cesspools and other substandard Title 5 septic systems in town through the following new regulations adopted in February:

• Cesspools and other substandard systems are deemed “failed” and will be required to connect to the sewer when it becomes available.

• If sewer is available to a property but the owner wishes to install a septic system, it must be fully compliant with Title 5 (no variances).

• The board further protects “Environmentally Sensitive Areas” (wetlands buffer zones, high groundwater levels, and flood zones) by requiring new, on-site septic systems in these areas to be fully compliant with Title 5 (no variances) and install I/A technology. Upgrades of septic systems in these areas must also employ I/A technology.

"Although Provincetown may be currently exempt from the enhanced Title 5 rules because we do not have any identified NSAs, this does not mean we are 'out of the water,'" Morse said. "The town continues to remain vigilant in protecting surface water and groundwater from pollution from other sources."

The town recently received grant funding to complete the fifth and last phase of installing porous pavement along the entire length of Commercial Street, expected to occur in 2024-2025. Provincetown has also received grants from the U.S. Department of Agriculture’s Natural Resource Conservation Service to improve three town stormwater outfalls.

"These projects will install additional infiltration beds upstream of the outfalls to reduce pollutants in stormwater runoff that drains to Provincetown Harbor," Morse said. "Initiatives like these have resulted in dramatic water quality improvements in Provincetown Harbor in the last two decades, improving the health of shellfish beds and restoring eelgrass beds."

What about the Pleasant Bay Watershed?

Towns in the Pleasant Bay Watershed, which have already been working for years on plans to reduce nitrogen pollution, have some time on their hands because they already have a watershed permit in place.

This watershed permit encompasses 21,600 acres in the four towns — 41% in Orleans, 30% in Chatham, 16% in Brewster and 13% in Harwich — and focuses on regional solutions to reduce nitrogen loading into the Pleasant Bay embayment system.

Like other plans approved or in the works around the Cape, according to the Cape Cod Commission, the plan under the Pleasant Bay permit calls for a combination of traditional wastewater management technologies, such as sewers, and non-traditional approaches, such as shellfish aquaculture to be implemented in coming years.

Brewster Town Manager Peter Lombardi said the new regulations "are actually modeled on the Pleasant Bay watershed permit that Brewster shares with Orleans, Harwich, and Chatham, which was the result of many years of successful collaboration between Brewster and our neighbors."

Brewster, for one, has already been "incredibly proactive in taking steps to protect our water resources," he said.

"Based on our current data and latest analysis, we do not expect that either the changes to the Title 5 regulations or the new watershed regulations will require the town to mandate installation of I/A septic systems or sewers in any part of town," Lombardi said.

Brewster has three other nitrogen-sensitive watersheds besides Pleasant Bay: Herring River, Swan Pond and Bass River. The town will likely need to only manage future development within the Herring River watershed through a new 20-year watershed permit under the new state regulations, and its contributions to Swan Pond and Bass River are considered "de minimis," meaning its obligations to address nitrogen in the southwest corner "will be very limited as well," he said.

What about the other Cape towns?

Cape Cod Commission Executive Director Kristy Senatori said many towns on Cape Cod have completed Comprehensive Wastewater Management Plans or similar plans for affected watersheds that would support applying for a permit for other watersheds. These towns include Barnstable, Sandwich, Falmouth, Mashpee, Yarmouth, Dennis, Harwich, Chatham and Orleans.

Moran corroborated that, saying MassDEP expects "a good number" of the towns, if not all, will seek a watershed permit that will give them and property owners within their Nitrogen Sensitive Areas more time to address the issue.

MassDEP has indicated that towns can apply for a single watershed permit that will cover multiple watersheds, which is helpful for towns, like Falmouth, that have numerous watersheds within their borders.

Meanwhile, Wellfleet has submitted a Targeted Watershed Management Plan for Wellfleet Harbor with the stated goal of also applying for a watershed permit, Senatori said. Truro is expected also to submit one of these plans. The Wellfleet Select Board approved that town's plan on June 23.

Organized into four phases over a 20-year period, the plan is based on a hybrid approach that "integrates both traditional and non-traditional technologies to reduce excessive nitrogen loads," prioritizing low-cost methods with rapid results, including a downtown sewer, installation I/A, septic systems, development of a permeable reactive barrier pilot project, salt marsh restoration, development of a sustainable shellfish habitat program, stormwater retrofits and construction of a neighborhood-scale wastewater treatment plant to facilitate an affordable housing project at 95 Lawrence Road that will connect to neighboring municipal facilities.

Wellfleet's hybrid plan, like those of other towns, also includes contingencies for traditional sewers and a wastewater treatment plant.

Some towns already have extensive sewer projects underway, including Barnstable and Falmouth.

More information about MassDEP's new regulations affecting the Cape can be found on the MassDEP website at www.mass.gov/regulations/310-CMR-15000-septic-systems-title-5

An interactive map of the affected watersheds can be found at: tinyurl.com/nitrogensensitivemap

Heather McCarron writes about climate change, environment, energy, science and the natural world. Reach her at hmccarron@capecodonline.com, or follow her on Twitter @HMcCarron_CCT

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This article originally appeared on Cape Cod Times: Cape towns must reduce nitrogen pollution. Which town is exempt?