UPDATE 1-Maine voters reject Quebec hydropower transmission line

(Adds lawsuit from transmission line owner, quote)

Nov 3 (Reuters) - Maine voters on Tuesday rejected a $1 billion project to bring hydropower from Quebec into New England, after a years-long battle that pitted clean energy advocates against local residents seeking to preserve the state’s pristine woodlands.

The fight over the so-called New England Clean Energy Connect (NECEC) project reflects the difficulty that developers face nationwide in siting new transmission lines. Many more must be built in the coming decades to modernize the nation’s creaking grid systems and connect far-flung renewable energy sources to population centers.

The owner of the transmission line, power company Avangrid Inc, swiftly filed a lawsuit in Maine Superior Court in response to the vote. The lawsuit argues that under state law, rules cannot be changed to stop a project.

Some 59% of Maine voters rejected the project, with nearly 90% of ballot stations reporting by Wednesday morning, according to local media outlets.

NECEC was meant to bring some 1,200 megawatts of Quebec hydropower to New England along a new 145-mile (233-km)transmission line through Maine’s northern forests. More than three-quarters of the corridor has already been cleared, with about 100 poles installed, Avangrid said last week.

Supporters of the project, including Avangrid utility Central Maine Power and HydroQuebec, billed it as a way to help New England states and the country fight climate change, since hydropower production emits no greenhouse gas emissions.

But opponents, supported by U.S. power company NextEra Energy Inc, which has competing generating projects in New England, argued that the line would cause permanent damage to Maine’s north woods and hurt the region’s tourism industry.

The fight for votes cost both sides almost a combined $100 million, making it the most expensive referendum question in Maine’s history.

The project was proposed in Maine in 2017 after a previous proposal to run a transmission line through New Hampshire was blocked by local opposition. It received a series of state and federal permits from 2019 to 2021 and began construction early this year.

“This referendum effectively tears up valid contracts, ignores the judicial and executive branches and goes back in time to retroactively change the rules to stop a project just because it threatens the financial interests of fossil fuel generators,” Thorn Dickinson, chief executive of NECEC Transmission LLC, a unit of Avangrid, said in a statement. (Reporting by Richard Valdmanis; Editing by Chizu Nomiyama and Peter Cooney)