Once upon a time most of our seafood came from our own watery backyard. But as our population has grown, especially along the coast, more and more local clam, mussel and oyster beds have become off-limits because of pollution. Today, 181,780 acres of Maine’s nearshore shellfish habitat are classified as having impaired water quality.

This reality was highlighted during an independent review of Maine’s shellfish growing area program completed in January. At that time, members of the joint standing committee on marine resources asked questions about why so many clam flats are closed, and thus require intensive sampling by the Maine Department of Marine Resources (DMR). The answer: bacterial pollution from human (and other animal) waste. While events like red tide and flooding can shut down great swaths of coastline (and generate much media attention), sewage pollution is the cause for most local and long-term closures.

Shellfish live in nearshore areas, placing them in close proximity to sources of bacterial pollution including malfunctioning septic systems. Clams, mussels and oysters are the equivalent to the canary in the coal mine, acting as sentinels for water quality problems. People who eat shellfish from polluted areas risk food poisoning and diseases like typhoid, hepatitis, norovirus, dysentery and gastroenteritis, although illness trends are hard to track because people don’t always report symptoms like nausea and diarrhea. To protect public health, Maine has strict standards for shellfish safety. Everything harvested and sold must be safe to be eaten raw.

The Maine coast is over 5,000 miles long and is home to half the state’s population (over half a million people). The recent review of DMR’s shellfish management confirmed that the agency does not have enough resources to efficiently and effectively survey the coastline for pollution sources.

In response, Reps. David Webster (D-Freeport) and Leila Percy (D-Phippsburg) have sponsored L.D. 2160, which would require that septic systems in shoreland areas are inspected and certified as working properly within three years prior to, or one year after, a property is sold. According to Webster, it only takes one failed system to close an entire shellfish area. The bill also contains language calling for the departments of marine resources, environmental protection, and health to work together. “The agencies stand behind this bill,” said Andrew Fisk, Director of the Bureau of Land and Water Quality at the Department of Environmental Protection, at a public hearing on the bill on Feb. 7. “It is a good idea. It improves on the existing program that requires us to identify and fix problems. This is very reasonable.”

As an example, Fisk offered the St. George River, where upgrades to Thomaston’s wastewater treatment plant opened up 1,800 acres to shellfish harvesting. When bacteria levels remained high in some of the smaller coves downstream, agency and municipal staff went door-to-door and identified 16 failing septic systems and 42 illegal discharges like sinks, washing machines, and “jerry-built” septics. Funding was provided to property owners for remediation, and another 500 acres of shellfish area opened. “But that is still not the end of the story,” continued Fisk, “Eternal vigilance is the price of shellfish. The 500 acres gradually ticked back down to 340 because we did not catch all the sources. Opening flats is not a one-time effort. It takes a lot of work beyond just inspecting septic systems.”

It is illegal to have a malfunctioning waste disposal system, but many people do not know if their system is functioning properly. A broken septic doesn’t always smell or bubble to the surface. Yet according to multiple testimonies presented at the hearing, most people will fix a system once they know it is failing.

The minimal cost of a septic investigation is $250. The 10,000 new subsurface disposal systems permitted annually by the Maine Department of Health and Human Services can cost anywhere between $7,000 and $25,000. Municipal wastewater treatment is costly, too. The 275,500 people in the Great Bay watershed of New Hampshire have spent four years and a million dollars analyzing their sewage disposal options, one of which is to pipe sewage out into the ocean.

This all seems like a lot of money. But what are the costs of not cleaning up our rivers and bays?

“When an area is closed to shellfish harvesting, the flow of income into a community is interrupted,” said Kevin Athearn, an economist from the University of Maine at Machias who recently completed an evaluation of the shellfish industry’s economic impact. At the Feb. 7 hearing, Maine shellfish growers expressed their support for L.D. 2160. “Development is an issue everywhere, and hopefully this will address some of the problems we are experiencing,” said Chad Coffin, president of the Maine Clammers Association, who delivered words in favor of the bill from harvesters in the Machiasport area.

Eric Horne, an oyster grower from Freeport, estimates that in clams alone, $29 million in revenue has been lost from Maine’s economy due to closures. Factoring in mussels and oysters would make the loss much worse. “Coastal pollution is contaminating clam flats, polluting our beaches, and putting people out of work, he said.