It’s getting a little noisier at night along West Sixth and Seventh avenues.

Lane Transit District work crews are joining Eugene Water & Electric Board workers in conducting nighttime preconstruction activities along those avenues, plus Charnelton Street, in preparation for the long-planned and long-debated west Eugene EmX project.

The LTD workers are excavating and surveying tree roots while EWEB teams work to move water and electricity infrastructure away from the project’s path.

The work is being conducted Sunday through Thursday nights, 7 p.m. to 7 a.m., and should last about a month.

At some points, lanes could be closed temporarily, but most likely during night hours only, said Lisa VanWinkle, a spokeswoman for LTD.

“It’s our belief that we will minimize (the construction) impact if we do the work at night,” VanWinkle said.

Members of the west Eugene EmX project — which include the project contractor Wildish, Sperry Tree Care and city of Eugene urban forestry employees — are excavating around the roots of about 25 trees that are not within the project boundaries but whose roots could be damaged by construction.

“If any of the trees have sent a significant number of roots under the roadway, (construction) could affect them,” VanWinkle said. “If the tree would then be less stable over time, then the decision would be made to remove that tree and put in a new tree.”

VanWinkle estimated that — aside from any trees that may need to be removed lest their roots be damaged by the work — 200 to 230 trees already come within the boundaries of the west Eugene EmX construction project area and will be removed.

“We’re trying to maintain as many trees as possible,” VanWinkle said. “We’ll be replacing (felled trees) at least one for one, if not more.”

LTD and EWEB crews will first complete the current section of preconstruction work, which goes from the downtown LTD station north onto Charnelton and west on Sixth and Seventh avenues to the Washington-Jefferson Bridge.

As soon as that portion is complete, crews will continue from where Sixth and Seventh avenues meet the bridge and work west to Garfield Street and south to West Broadway.

The work is just one aspect of preconstruction activity that will take place in coming months. Gas and fiber telecom utilities, including CenturyLink and Comcast, also will be working periodically to move communication utility infrastructure away from the construction site.

The road and sidewalk construction of the actual 4.5-mile-route is slated to begin in late summer or early fall.

“The plan is to begin on Seventh Avenue at Garfield and work our way eastward,” VanWinkle said of the full construction phase.

Work on Sixth Avenue, and Charnelton and Garfield streets, is to be completed before construction begins on the West 11th Avenue segment of the route.

“The idea is that we’re trying to minimize the amount of time that we’re in front of any individual business,” she said.

The $95 million bus line will run from the downtown Eugene station to near Randy Papé Beltline in west Eugene, following West Sixth, Seventh and then 11th avenues.

Portions of the route will be in dedicated bus-only lanes and other portions will be in lanes shared with other traffic.

Work is being conducted as a federal judge in Seattle prepares to weigh arguments in a lawsuit aimed at stopping the project.

The Eugene group Our Money Our Transit has sued the Federal Transit Administration, alleging that the agency allowed the project to move forward based on flawed environmental studies and without carefully considering alternatives.

The federal agency and LTD, which has intervened in the case, are asking U.S. District Court Judge Thomas Zilly to dismiss the lawsuit. The parties have filed their written arguments.