YORK COUNTY — A typical Unitil natural gas customer in Maine could see their cost rise more than 9 percent next year if a proposed rate increase is approved.

Unitil Corporation provides electricity and natural gas in Maine, New Hampshire and Massachusetts and has 105,600 electric customers and 82,700 gas customers.

The utility provider has filed a request with the Public Utilities Commission to increase its natural gas distribution rates in Maine.

Unitil has asked the Maine Public Utilities Commission for an increase of $7 million in base revenue, which would be an increase of about 7 percent of the 2018 operating revenue, according to a press release from the utility company. The utility has asked that a rate increase begin in August of this year, but expects if approved, it will not go into effect until April 1, 2020.

Unitil officials say that if the requested rate change is approved, the typical gas heat customer using 68 therms a month would see a monthly increase of slightly more than 9 percent, or $9.90.

The company is making the request to cover costs for improvements to the system to increase safety and reliably serve a growing number of customers, according to the press release.

The filing also includes a proposal by the company for an alternative rate mechanism called the Capital Investment Recovery Adjustment for a period of three years which will allow for the recovery of costs associated with non-growth capital projects due to the need to relocate, upgrade, replace and abandon existing distribution facilities, according to the press release.

“All Until natural gas customers in Maine would be part of the proposed rate increase,” said Until spokeswoman Carol Valianti in an email.

Valianti said Unitil has more than 1,900 natural gas customers in York County, serving Biddeford, Eliot, Kennebunk, the U.S. Navy Shipyard in Kittery, North Berwick, Old Orchard Beach, Saco, Sanford, South Berwick and Wells.

According to information from the Maine PUC, Unitil’s rates are determined through a three-step process.. The first step is the revenue requirement, or what the total cost is to serve the customer, including operation and maintenance costs and a return on investment. After this is determined, sales by customer class are estimated for the same period and lastly, revenue requirements are then allocated to each customer class based upon the cost to serve each class.

— Staff Writer Liz Gotthelf can be reached at 780-9015 or by email at egotthelf@journaltribune.com.