The Mactaquac hydroelectric generating station is nearing the end of its service life and the process of determining what to do with the dam is underway.

The hydro-dam on the St. John River was supposed to operate through 2068, but the rate at which its concrete is deteriorating means it will have to be replaced or removed by 2030.

On Tuesday, NB Power laid out three options it’s considering as it embarks on a technical review of the Mactaquac Dam, with associated costs estimated to be in the range of between $3 billion and $5 billion.

“Status quo is not an option, so we do have to make sure that the choices that we make, going forward, are the most economic, and those factors will all be considered into our recommendations,” said Keith Cronkhite, NB Power’s vice-president of generation and business development.

NB Power is trying to determine whether it should replace the dam and install a new hydro generator, remove the generator but maintain the dam, or to remove everything and restore the river’s natural flow.

Over the next year, NB Power will examine the impact of the options in what it’s calling a comparative environmental review, which would precede a formal environmental impact assessment.

“It would not allow us to bypass that particular process,” Cronkhite said.

“We would use the information gained through the comparative environmental review process as an input to the formal process.”

NB Power also has renewable energy targets to consider, something the Mactaquac Dam is a big part of.

“In the absence of those facilities, we would certainly have to look at other alternatives,” Cronkhite said.

The energy utility will also consider the impact its plans could have on various communities, including six First Nations situated along the river.

“Our intent is not to ask the Nations which option is preferred, but rather to determine what the impacts of each option (are), and how they relate to the Nations themselves,” said Ryan Dunbar, a member of the Kingsclear First Nation.

Of the three options on the table, NB Power says it doesn’t have a preference yet.

The utility says it will use the process it’s just embarked on to determine its preferred option.

With files from CTV Atlantic’s Andy Campbell