WINDHAM – A plan to bring sewer to North Windham and Windham Center has been scaled back considerably, to $37.9 million, though town officials are still unsure of who would bear the cost of the project.

The Windham Town Council on Tuesday heard from Woodard & Curran engineering consultant Barry Scheff, who last August estimated the cost of constructing the entire system at once at $67.8 million. That price could have gone up as much as 50 percent or down by 30 percent, depending on what was encountered once the project began. The potential $100 million price tag, not including debt service, was a little steep for councilors and residents who weighed in at public hearings last year.

Scheff’s refined $37.9 million figure – which has a minus-25 percent to plus-30 percent estimation – only includes a sewer along the Route 302 corridor from the Raymond line to Westbrook, including offshoots running along Route 115 to its intersection with Falmouth Road and another pipe linking the school complex in Windham Center to the rotary.

The pared-down design, known as the system’s “spine,” would also include six above-ground pump stations pushing the effluent toward the Portland Water District’s wastewater treatment facility on East Bridge Street in Westbrook. The pump stations would be located on land the town already owns or would acquire.

Scheff spent about four months honing the scope of the project, mainly because councilors want to be able to know what the project would cost before asking taxpayers or users to foot the bill. With help from Councilor Peter Busque and his ties with local excavators, Scheff interviewed numerous local contractors who have experience with soils in the Route 302 corridor.

Scheff also met with Portland Water District officials, especially for the portion that would run through Westbrook on Route 302. Scheff eventually drafted a planned sewer route, which he predicted, based on the local input, would have about 50 to 60 percent surface bedrock. Knowing how much ledge is in the route is important since project costs go up with more ledge.

Water works

At Tuesday night’s meeting, Town Manager Tony Plante once again explained the need for the sewer. He said the town has been studying the effects of commercial development in North Windham since the mid-1990s and has hydrogeology graphs showing a rising number of nitrates concentrated in areas under large septic systems for big-box stores. (Nitrates reduce the body’s ability to take in oxygen, and are a health risk especially for infants and children, according to National Institutes of Health.) None of the graphs, however, show dangerous levels of nitrates, although recent years show the trend moving closer to the federal drinking water safety limit of 10 milligrams of nitrates per liter.

Plante also reminded councilors that most of North Windham is supplied with drinking water from the Portland Water District so few people get their drinking water from private wells. The purpose of the sewer would be to remove the estimated 700,000 gallons of wastewater that is filtering each day through hundreds of septic systems into the North Windham Aquifer, the largest sand and gravel aquifer in Maine, Plante said. By removing the wastewater, Plante said, the extensive aquifer – which may be needed in the future if something happens with Windham and the Portland Water District’s water source, Sebago Lake – could be spared excessive environmental damage.

“Most of North Windham, and in fact most of Windham, is on public water, so the public health risk is relatively small. There are still people who are on private drinking water wells and the way to deal with those, frankly, is not with a $68 million or $38 million sewer project. The way to deal with that is to find an alternate source of drinking water,” Plante said. “But long term, if we continue to add contaminants to the groundwater, at some point that groundwater resource may be needed as a source of drinking water for this area. … We’re looking at the … economic development potential of the community that will at some point be compromised if we don’t find another way to collect and treat the wastewater.”

Plante said the pipes that would be installed along Route 302 as part of the $37.9 million project would be able to handle future sewer expansion should the town decide to expand the sewer to areas of town outside the Phase 1 areas of Route 302, Windham Center and Mill Pond. Scheff added that the pipes have at least a 50-year lifespan and could last up to 100 years as some of the Portland Water District’s network in Portland has.

Payment programs

More so than in previous discussions, councilors and town staff touched briefly on who would pay for the sewer. Councilors have stayed away from the discussion, mainly because it wants to first get an accurate figure on what areas should be serviced, exactly how much it would cost and whether outside sources can be found through state, federal or institutional grants.

Much of those extra-local financial resources have dried up in recent years as the economy has taken a toll on federal and state budgets. And, as Plante put it, “the Clean Water (Act) funds are tapped out, have been for a long time. The time when Windham could have gotten 75 percent of the money from the [federal Environmental Protection Agency] for a project like this are history, long gone.”

Scheff provided an estimate of $933 per user per year to pay for the $37.9 million system and ongoing maintenance. That cost would increase depending on actual usage, with commercial users having to pay a higher share.

But with Plante saying that “a well-functioning residential septic system isn’t the problem, it’s the large-scale commercial septic systems that are the bulk of the problem,” it is unclear at this point how the project would impact local businesses or taxpayers. That discussion, as councilors agreed on Tuesday night, has been put off until September, when Scheff will come back with different payment scenarios.