CUMBERLAND, Maine — Installation of natural gas lines throughout Cumberland, Falmouth and Yarmouth will begin in late April or early May next year, Cumberland Town Manager Bill Shane said Monday.

Installation of the main line could be half complete by the end of 2014, representing an approximately $42 million investment in the three towns, with possibly 10 percent of residential lines in Cumberland possibly completed, Shane said.

The entire project is expected to take between three and five years.

The three town managers met with Summit Natural Gas representatives and their design team last week to discuss the construction schedule, as well as training and certifying local contractors. All three town councils in February endorsed Summit’s proposal to extend service into their towns.

Shane has said the Colorado-based company’s project would include laying 1.2 million feet of pipe in the three towns, where leaders see natural gas as a less expensive heating fuel than oil.

A natural gas pipeline already runs through the western part of Cumberland. Summit will tap into that line near the Cumberland County Fairgrounds, and the line will run down Blanchard Road to Tuttle Road, and to Routes 1 and 88, before branching out south to Falmouth and north to Yarmouth.

“As the main line gets put in, [Summit will] be following behind with getting homes signed up,” Shane said. “They hope to have gas flowing by the end of 2014.”

The manager said he hopes town and school buildings will be connected by that time. He also would like the company to extend the line from the intersection of Blanchard and Skillin roads to the town fire station on Blackstrap Road, since its heating system needs to be replaced.

As part of this summer’s Blanchard Road reconstruction project, 6,000 feet of piping was already installed.

“Our biggest concern, and all three towns have the same issue, is not the infrastructure work, but the communicating to the homeowner,” Shane said — educating residents about what they must do to connect, if they wish to switch to natural gas.

An education campaign will run through early next year, he said.

Summit is not going to run gas lines to neighborhoods based on speculation, but on how many customers commit to connect, Shane continued. If most of a neighborhood does not want to connect, natural gas will likely not be extended to it. He said he hopes homeowner connections will occur sooner rather than later, to work in conjunction with the town’s long-term paving program.

Summit has projected 86 percent saturation in the three Cumberland County communities within five years, or nearly 7,700 customers, and 95 percent saturation within eight years, or more than 9,100 customers.

“We’re truly looking forward to it, and we’ll have more information as we get more information from Summit,” Shane said.

The towns expect by January 2014 to have a specific list of where installations will take place in the next few years, he said.