The Selectmen on Tuesday set the cost to extend the sewer project to the Oakdale and Cromsett neighborhoods at $18,000 per property, in accordance with a Town Meeting vote that capped the cost, though how the town will pay the difference between what residents will pay and what the project actually costs remains unknown.

The "betterment fee" -- the amount that each property-owner must pay when the sewer system is expanded to a neighborhood -- is traditionally set by dividing the total cost of a sewer project by the total number of properties in the neighborhoods in the contract.

But the rate for the Oakdale and Cromesett neighborhoods' project was capped at $18,000 at Town Meeting this fall, after residents argued that the process for assessing the betterment was flawed.

If voters hadn't OK'd the cap, the total cost per resident would actually be $21,339. The Selectmen are still grappling with how to cover the $915,000 shortfall created by the cap.

“It is incumbent upon this board to find a way to cover this deficit,” said Selectman Cara Winslow. Winslow pointed out that a funding source would need to be determined soon, in order to put the fee on the 2014 tax bills. “I would respectfully ask that we keep this on the agenda until the matter is resolved."

The Selectmen voted 4-1 to set the fee at $18,000, with Selectman Ellen Begley in opposition.

“Just leaving this on here doesn’t move the football,” Selectman Chair Steve Holmes replied. “We’re going to set the betterment rate, and then the town needs to bond that money.”

Whether or not the town will be able to borrow enough money to cover the full deficit is not known.

“I think it really hinges on what we can borrow, and what our bond rating is,” said Selectman Peter Teitelbaum.

In other sewer news, the betterment interest rate for residents Oakdale and Cromsett was bumped up to 2.5% from 2%. This was done based on advice from Treasurer/Collector John Foster, according to Winslow. The vote was 3-1-1, with Begley voting no, and Selectman Alan Slavin abstaining.

The Selectmen also discussed placing an article on the spring Town Meeting warrant that would create a board of Sewer Commissioners, separate from the Board of Selectmen.

The proposal was actually passed at Town Meeting in October of 2010, but effectively died in the state Legislature after it sat in limbo due to issues with legal wording. A new article was submitted to Town Meeting in the fall, but was sent to further study by voters.

Winslow expressed concern on Tuesday that “drastic changes” were made to the article between the 2010 Town Meeting, when it was originally approved, and 2012. “I think we should discuss the article, and whether we should put forth a new one,” said Winslow.