Construction on the Canadian portion of an international power line that will allow more electricity to flow between Maine and New Brunswick was officially announced Tuesday.

The 145-mile, 345-kilovolt transmission line, known as the Northeast Reliability Interconnect, is the result of a collaboration between Bangor Hydro-Electric Co. and New Brunswick Power. The line was proposed to increase the reliability, stability and efficiency of electric delivery systems on both sides of the border.

“The international power line project will improve system efficiency by reducing losses for delivery of energy for our customers,” said David Hay, president and CEO of NB Power.

Presently, the Maine Electric Power Co. line is the only connection between Maine and the Maritime provinces.

Construction on the 85-mile-long Maine portion of the line began in July. The Maine portion of the Northeast Reliability Interconnect route begins in Orrington and follows, for the most part, existing transmission lines and natural gas pipelines until it reaches the St. Croix River near Baileyville where it will connect with the Canadian line when that project is completed. The 60-mile-long Canadian section of the transmission line will connect to a substation near the Point Lepreau nuclear power plant.

“In about a year’s time, our two projects will be joined together as one international transmission line,” said Rob Bennett, president of Bangor Hydro.

The line is scheduled to be in service by December 2007.

The Maine section of the line will be owned and operated by Bangor Hydro. The New Brunswick section will be owned and operated by NB Power.

The New Brunswick government also is investing about $1.4 billion in overhauling the 23-year-old Point Lepreau nuclear power plant to extend its life by another 20 to 25 years. That project has a September 2009 completion date.