WILTON — The Board of Selectpersons on Tuesday held off awarding a contract for construction at the Wilton Wastewater Treatment Plant because $4.16 million is still needed.

Bids were opened Aug. 7 and the lowest was $9.55 million from Penta Corp. of Moultonborough, N.H., William Olver of Olver Associates of Winterport, told the board. The bid was lower than the $9.9 million engineers estimated for construction for the second phase of the upgrade.

Superintendent Clayton Putnam said $4,164,149 is still needed.

Olver Associates developed the upgrade plan, which was split into two phases to help the town acquire grants and loans. Upgrade plans were started in 2010 for the then 32-year-old plant and pump stations at an expected $9.5 million cost.

Now, the cost is $10.86 million for just phase two, Putnam said.

Initially, phase one consisted of upgrades to 31 pump stations and the front part of the plant, he said. But the town was advised to reduce the scope of phase one and have only one contractor involved in phase two, he said. The pump stations have been renovated but nothing has been done to the plant, he said.

Reasons for the increase, in addition to rising costs over the past five years, include that renovation work initially cut from the project now needs to be included, Putnam said.  

“In hindsight, we shouldn’t have cut it,” he said of the $1 million in renovation work cut. 

The work has also expanded because one need developed into more needs to address the aging plant that surpassed its 20-year life span. In addition, regulations have become stricter.

“We have not failed one toxicity test,” he said of water quality testing done since 1987.  

The size of Wilson Stream where treated water is released means more regulation, he said.

Some funding is left over from phase one but the board agreed to wait to see how the U.S. Department of Agriculture’s Rural Development program could help with any additional grants and loans.

Once known, the board will need to bring it to a public hearing and a vote at a special town meeting, Town Manager Rhonda Irish, said.

The town has 120 days, or until Dec. 7, to award the contract, Putnam said.

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