DETROIT, Maine — Central Maine Power’s Maine Power Reliability Program is on schedule and on budget, said CMP spokesman John Carroll.

The $1.4 billion project that started in September 2010 stretches from Eliot on the New Hampshire border up to Orrington.

“What we are doing is doubling up the number of lines in our 345 [kilovolt] system,” said Carroll.

The 345kV lines are the highest tier of lines run, he said. The voltage drops from each tier until it brings 240 volts to someone’s home. Carroll likened it to a highway system.

“Major interstate lines are at 345kV. Primary routes like, Route 1 or 2, would be 115kV,” said Carroll. “Those carry power between major substations through major metropolitan areas. It steps down to 34.5kV. That would be similar to a state-owned road, not a numbered highway.”

The lines step down to 12,470 volts and then to 240 volts, he said. The hierarchy allows CMP to move larger amounts of power along longer distances.

In addition to lines and poles, 14 substations also are being constructed. Some of the help is coming from Bangor Hydro and Public Service New Hampshire.

The system was in need of an upgrade because the current setup was designed in the 1960s, he said.

“The equipment still works just fine. The system will become obsolete in some respect,” said Carroll.

Carroll said the geographic energy load has shifted to the south and coastal regions. Loads also have doubled since 1971, when the system was first energized.

The construction project directly affects more than 70 cities and towns in the state. Carroll said CMP is generally using existing corridors, but some places needed to be widened. In some cases, the company has had to buy additional land.

“It’s the largest construction project undertaken in Maine,” he said. “Geographically, it’s the largest transmission ever done in New England, at least in recent history. It’s very timely for Maine. It’s generating a lot of employment.”

Carroll said CMP estimated that between 2,500 and 2,700 people work on the project on a daily basis. The project is so big that CMP had an economic impact study done by the University of Southern Maine.

“For every three jobs directly involved in the project, roughly one additional job would be indirectly created,” said Carroll, mentioning those jobs range from those who supply materials to waitresses near construction sites. “Between 700 to 900 people have jobs because of the project. It’s very satisfying for us.”

He added that of the 350 contractors working on the project, about 270 of them are based in Maine.

Mainers won’t have to bear the brunt of the cost either, said Carroll. About 50 percent of the project is financed through equity from Iberdrola, the Spanish parent company of CMP. The rest is borrowed. CMP will make the money back through ratepayers. Maine ratepayers will be responsible for 8 percent of the project, while other New England customers will pick up the rest. On the flip side, Maine ratepayers are responsible for 8 percent of any ISO New England project, even if it doesn’t directly benefit Maine.

“It’s an exciting project for a company of our size. It’s exciting to know that we can make an investment like this and have the employment it’s created,” said Carroll. “We’d like to think we’ll be in position to provide reliable service for the next several decades.”

Carroll said the project should be completed in the second quarter of 2015.