Company building up a head of steam for the Fenway

Vicinity Energy is planning a half-mile pipe from the Back Bay to the Fenway Park area to provide steam heat to all the new buildings going up or planned on and near Brookline Avenue.

The company, formerly known as Veolia, goes before the Boston Conservation Commission on Wednesday because part of the plan calls for replacing an abandoned 12-inch water main on a decaying wooden bridge over the Muddy River between Ipswich Street and the Worcester Line train tracks with a new 18-inch steam pipe.

The abandoned pipe, from the air and from the Fenway side of the Muddy River, from the Vicinity filing:

In its filing, Vicinity says:

The Fenway Steam Line Extension Project will expand Vicinity's steam line infrastructure to proposed and existing developments in the Fenway neighborhood. Increasing steam service throughout the city contributes to Vicinity's ability to decarbonize the Boston district energy system. Decarbonizing aligns with the environmental goals set by the Commonwealth of Massachusetts and environmental legislation within the Cities of Boston and Cambridge.

The new pipe would start at an existing Vicinity manhole on Boylston Street at Massachusetts Avenue, continue under Lansdowne Street and terminate at Brookline Avenue - basically where WS Development has approval for its massive Fenway Corners development.

Vicinity's environmental consultant wrote the Muddy River work would have no environmental impact - and that not replacing the defunct water main and its current bridge could cause problems should they collapse into the river.

The filing adds the rest of the pipe would be underground and that:

Proposed steam manholes will be installed every 300 linear feet. All sidewalk and roadway materials affected by the steam line installation will be replaced in-kind.

Conservation Commission hearings begin at 6 p.m. on Wednesday.

Vicinity Energy Fenway notice of intent.