ST. ALBANS — New Environmental Protection Agency (EPA) limits on phosphorous allowed into Lake Champlain would require reductions from all sources, says a watchdog group’s lawyer.

Conservation Law Foundation (CLF) senior attorney Anthony Iarrapino commented on the issue as the EPA considers ramping up restrictions on permitted sources of pollution, such as large-scale business and housing developments and wastewater treatment facilities. To head off those restrictions, the state will have to demonstrate a willingness to make the regulatory changes and provide the funding necessary to reduce pollution from other sources, such as agriculture, roads and streambank erosion.

It was a legal challenge filed by Iarrapino on behalf of CLF that led the EPA to reopen Vermont’s Total Maximum Daily Load (TMDL) rules for phosphorous in Lake Champlain.

The Vermont Agency of Natural Resources (ANR) anticipates that new EPA requirements next year will require substantial reduction to the amount of phosphorous permitted to reach Lake Champlain. Vermont’s citizens and officials must now decide how to achieve those reductions and how to pay for them.

Phosphorous is the nutrient responsible for blue-green algae blooms and rampant weed growth in the lake.

“The historical concern of CLF is the cleanup of Lake Champlain has been a shell game,” said Iarrapino. He explained that whenever concern was expressed about the pollution caused by one group, for example farmers or large developers, the members of that group would call attention to another source of pollution.

“We’re breaking down that shell game and sending the message quite clearly that the problems of the lake are so severe no one gets to sit on the sidelines,” said Iarrapino. “Every pollution source is going to have to be part of the solution.”

The science underlying the TMDL, which preliminary numbers have put at 500 metric tons of phosphorous per year, is sound, said Iarrapino. The recognition that the whole gamut of phosphorous sources will need to be addressed is being driven by the science, in his estimation.

That science indicates the amount of phosphorous going into the lake from Vermont must be reduced by nearly 40 percent.

EPA has constructed a model that allows scientists to input a phosphorous reduction target and then examine the various combinations of changes to land use practices and stormwater management that would achieve the goal, according to Iarrapino.

When the Vermont Legislature resumes in January, policymakers will need to make decisions about what regulatory changes will be made and how many resources Vermont is willing to commit to lake cleanup. That opens up political questions as to who will pay and how much.

Under the old TMDL, written in 2002, Vermont promised to reduce pollution from sources other than wastewater treatment facilities but failed to fulfill those promises, said Iarrapino.

Because wastewater treatment plants are easy sources of phosphorous to identify and control, they are likely to be targeted if Vermont cannot convince EPA it is serious about cleaning up other sources.

“If we can’t get the pollution from these other sources way down then sewage treatment plants and other sources that are easy to control will have to go to zero,” said Iarrapino. Under the federal Clean Water Act, if progress is not being made on cleanup of a water body then permitted sources must be brought to zero, he explained.

“EPA is going to flex its authority in the areas where it’s easiest to do. … If the state thinks it has a better idea it better put that idea on the table and provide the resources to implement it,” said Iarrapino.

Residents of municipalities with wastewater treatment facilities “need to speak up and they need to speak up for fairness.” Improving the technology at use in the state’s wastewater treatment facilities would cost millions.

One of CLF’s concerns is how the costs of the cleanup will be allocated. In particular, CLF wants to see private sector polluters bear the costs for cleaning up the pollution they generate, explained Iarrapino.

“We’re being very clear which expenses are expenses that should be borne by taxpayers and which should be borne by private interests,” said Iarrapino.

ANR is gearing up for a series of public meetings this fall and winter, but thus far Gov. Peter Shumlin has been mostly silent on the question of the TMDL and the resources and regulations that may be necessary to meet it.

“I think the governor is going to see there’s tremendous potential upside in taking on the lake and clean water more generally,” said Iarrapino. Tackling the cleanup of Vermont’s waters could win the governor more supporters, he suggested.

Based on the public statements of ANR officials, “you have to believe this is an administration that is committed to getting the job done,” said Iarrapino. However, he also noted that so far ANR has only offered words, not taken any action to strengthen pollution regulations, some of which can be done by ANR itself without the involvement of the legislature.

Cleaning up Lake Champlain also will have benefits for people living miles from the lake. Reducing the pollution in the lake, means reducing the pollution in the rivers and streams flowing into it. Reduced pollution will lead to improved fish and wildlife populations, suggested Iarrapino. The stream and river management policies needed to reduce pollution are in many cases the same policies needed to reduce flood risk, he and others have noted.

The TMDL situation has created an opportunity for Vermont to do what’s necessary to clean up Lake Champlain, in Iarrapino’s view. “The cost of not stepping up to the plate is going to be much higher in the long run,” he said, pointing out that every year pollution is allowed to flow into the lake increases the amount of time and work needed to clean it.