Home » A Major Victory to Reduce One of The Largest Sources of Pollution to Casco Bay

A Major Victory to Reduce One of The Largest Sources of Pollution to Casco Bay

As the Clean Water Act turns 50, Friends of Casco Bay celebrates new permit to reduce stormwater pollution.

Stormwater is one of the largest sources of pollution into Casco Bay. Yet, until this year, Maine has not required clear, specific, and measurable terms in the permit that controls discharges from large urban stormwater systems.

Thanks to the advocacy of Casco Baykeeper Ivy Frignoca and Friends of Casco Bay’s partners around the Bay, the state has issued a revised municipal stormwater permit that contains much-needed protections to reduce stormwater pollution flowing from the most urbanized communities in the state. 

Under the Clean Water Act, reducing and eliminating the pollutants that flow through municipal separate storm sewer systems (or “MS4s” for short) is regulated by a general permit issued by the Maine Department of Environmental Protection (DEP). In a city like Portland, these stormwater systems include the streets, storm drains, gutters, roadside ditches, and sewers that discharge untreated stormwater runoff into local waterways, some of which drain into Casco Bay. 

Maine’s new MS4 permit will implement three major changes that should significantly reduce stormwater pollution into Casco Bay and its tributaries. Municipalities that fall under the permit will be required for the first time to:

  • Test stormwater outfalls to identify and eliminate sources of bacterial contamination
  • Develop and adopt an ordinance to require new construction and redevelopment to use low impact development techniques that allow stormwater to flow more naturally and carry less pollution into stormwater systems
  • Take three actions to restore water quality and reduce pollution from their stormwater systems where it flows into impaired waters.

It took five years of advocacy by Friends of Casco Bay and scores of meetings, comments, and proceedings to ensure these vital protections were included in Maine’s new MS4 permit.

“This is a time to celebrate,” says Casco Baykeeper Ivy Frignoca. “The changes in this permit should have huge and visible results for our watershed. What better year to have this permit take effect than during the 50th Anniversary of the Clean Water Act. Stormwater harms the Bay in so many ways because it carries diverse and varying loads of pollutants. For example, excess nitrogen fertilizes nuisance and sometimes harmful algal blooms. Toxins can poison wildlife and degrade ecosystems. Too much bacteria closes clam flats. As climate change brings more and stronger storms to Maine, the impacts of stormwater pollution will worsen without these changes.”

Conjure an image of Casco Bay. Do you see healthy, blue-green water? Most likely.

Yet anyone who has seen Casco Bay after a large rain might conjure a different image, where that vibrant blue-green is replaced with plumes of murky, brown stormwater.

After a rainstorm, millions of gallons of polluted stormwater pour into Casco Bay.

Stormwater is one of the largest sources of pollution into Casco Bay. Stormwater is a problem because our roads, driveways, parking lots, and buildings do not allow rain to soak into the ground and be filtered through natural processes. When snow melts in the spring or rain falls, water rushes over our cities and towns, collecting a toxic slurry of pesticides and fertilizers from lawns, exhaust and salt from roadways, pathogens from pet waste, and so much more. In urbanized areas, much of this polluted runoff drains into municipal storm sewer systems that discharge into streams, rivers, and, ultimately, Casco Bay.

There are solutions to this modern problem. By using low impact development techniques, green infrastructure, and testing and investigating sources of contamination, we can drastically reduce this pollution.

A map of MS4 program in the Casco Bay Watershed
A map of MS4 communities in the Casco Bay watershed, provided by the Casco Bay Estuary Partnership.

The new MS4 permit will go into effect in July of this year. In the Casco Bay watershed, it applies to twelve municipalities and specifically regulates stormwater pollution in their most densely populated areas. The municipalities include Scarborough, Cape Elizabeth, South Portland, Portland, Falmouth, Cumberland, Yarmouth, and Freeport along the coast, as well as inland communities such as Windham, Westbrook, and Gorham.

Doug Roncarati is a Stormwater Program Coordinator for the City of Portland. “Everything we do on the landscape has the potential to create some kind of pollution,” says Doug. “The environment is very resilient, but throw too much at it over time and it will break down. We protect the environment and the long-term economic wellbeing of our communities by being thoughtful in how we manage our water resources. The MS4 permit is one way we can do that.”

MS4 permits, like all Clean Water Act permits, are renewed every five years. The renewal process provides the opportunity to assess if the permit sufficiently protects water quality or if there are improvements that need to be made. The process also allows for incremental advances that recognize budget constraints, developments in knowledge and technology, and the reality of what can be accomplished in five years. 

MS4 permits that apply to municipalities are required to contain “clear, specific, and measurable” terms to address stormwater pollution, according to a federal court ruling from 2003. In short, this ruling required environmental agencies like the Maine DEP to clearly describe how permitted municipalities should address stormwater pollution. When Maine’s MS4 permit was due to be renewed in 2018, Ivy knew there were important improvements to be made. The last version of the permit issued in 2013 did not include “clear, specific, and measurable” terms to reduce pollution.

“The requirement to set forth ‘clear, specific, and measurable’ terms in MS4 permits may be the best thing to happen for our watershed in a long time,” explains Ivy. “It fundamentally changed how MS4 permits could be written and gave Friends of Casco Bay the foundation to advocate for new permit language that will effectively reduce pollution from past actions and ensure future development does not degrade our waters.”

When the state began the permit renewal process in 2017, Ivy submitted comments on the first draft advocating for these new terms. However, for DEP and many municipalities, implementing a stronger MS4 permit would require valuable time and resources. Over the next four years, Ivy continued to advocate for stricter standards and filed more than eight sets of comments on drafts of the permit.

Ultimately, Friends of Casco Bay filed an appeal to the Maine Board of Environmental Protection asking that the new “clear, specific, and measurable” terms that Ivy had advocated for be included in the permit. In the summer of 2021, the Board of Environmental Protection sided with Friends in the appeal, and Maine’s new MS4 permit was finalized on December 23. In order to provide DEP and affected municipalities additional time to prepare to implement the new terms, it was agreed that the permit would officially go into effect on July 1, 2022.

Will Everitt, Interim Director of Friends of Casco Bay, sees this victory as a great example of how Friends works. “This was a long and challenging process,” says Will. “The way we advocate for the health of the Bay is just as important as what we achieve. We have deep respect for the DEP and affected municipalities. While we sought to address what may be the biggest source of pollution into the Bay, we also worked hard to collaborate with our partners and listen to concerns throughout the process.”

Stenciled storm drain reads, "do not dump, drains to Casco Bay."
A stenciled storm drain at Bug Light in South Portland reminds the public that what goes down the drain ends up in Casco Bay.

Today, there are more people living by and working on Casco Bay than ever before, and as our communities grow, so do our impacts on the health of the Bay. Climate change brings additional challenges to the coast, such as altering ocean chemistry and intensifying rainstorms that will send more stormwater into Casco Bay.

Damon Yakovleff, Environmental Planner at the Cumberland County Soil and Water Conservation District, provides technical support to municipalities on stormwater and sustainability projects. “This permit is a part of the broader effort to make this a truly sustainable region that treads more lightly on the environment,” says Damon. “It matters in a holistic way. It is about preventing water pollution, but it goes far beyond that. It’s about supporting our economy, culture, and quality of life.”

The MS4 permit’s new stormwater protections that go into effect beginning this year will help reduce these threats. A healthy Bay is a resilient Bay. With less pollution flowing to our coastal waters, Casco Bay and our coastal communities will be better prepared to withstand the challenges we know are looming on the horizon.