Environmental activists warn that construction of a 21-mile natural gas pipeline through northern Baltimore and Harford counties could affect the region's drinking-water system, as the $180 million project cuts across more than three dozen streams feeding into Loch Raven Reservoir.

Theaux Le Gardeur, executive director of the Gunpowder Riverkeeper, has petitioned the Federal Energy Regulatory Commission to reconsider its approval of the pipeline last month and order a more detailed review of the project's environmental effects.


Columbia Gas Transmission plans to extend a 26-inch-diameter pipeline from Owings Mills to Fallston, to be built largely alongside another line. The Charleston, W.Va.-based company hopes to begin construction early this year but still needs approvals from state and federal regulators for the project's impacts on streams, wetlands and other sensitive environmental areas.

"We have designed the … project to minimize environmental impact, while ensuring that we accomplish the critical goals of improving the safety and reliability of natural gas delivery for tens of thousands of Maryland residents," said Brendan Neal, the company's community relations manager.

Some residents along the proposed route, many of them worried about possible leaks or explosions near their homes, oppose the project. Advocates of Oregon Ridge also object to the pipeline's cutting through Baltimore County's largest park, clearing forestland, disturbing wildlife and possibly affecting a swimming lake.

Le Gardeur's group and 17 other environmental and community organizations believe potential effects on the region's drinking water system have not gotten the attention they deserve. Of 70 waterways the pipeline would cross, 39 are sources of the region's drinking water.

"They're not looking at the cumulative impacts," said Le Gardeur, who is also a fishing guide and tackle shop owner in Baltimore County.

Loch Raven, a 2,400-acre man-made lake north of the Beltway, is the largest of three area reservoirs that furnish drinking water to nearly 1.8 million residents of Baltimore City and the surrounding counties. Its main tributary is the Gunpowder Falls, and all the creeks draining into it spread across 218 square miles, reaching into Harford County and Pennsylvania.

Though the region's drinking water is treated by the city to meet health standards, the raw water in the reservoir contains elevated levels of some pollutants. Six years ago, the Environmental Protection Agency approved a state plan for reducing two of those pollutants: phosphorus and sediment. Excessive phosphorus can trigger algae blooms, affecting water quality, and sediment buildup can fill in the lake, reducing its capacity to supply drinking water.

Le Gardeur said more phosphorus and sediment could be flushed into the reservoir by construction across the streams and by disturbance of 305 acres of land as the pipeline is laid. Even if the project must go forward, he said, Columbia ought to be required to minimize disturbance of streams and banks by drilling the pipeline under the beds.

Such "horizontal directional drilling" is often used to reduce harm to sensitive areas but is more expensive. The U.S. Fish and Wildlife Service and Maryland Department of Natural Resources, citing similar concerns about stream disruption, also called for drilling under at least some of them.

The company has proposed instead to do "dry-ditch" crossings, temporarily damming and piping the water around a stretch of streambed while construction equipment excavates a trench for the pipe. Neal, the Columbia spokesman, said "preventative measures" would be taken to safeguard water quality and fish populations, and the work would be monitored by federal, state and local authorities.

"Once construction is completed, streambeds will be restored to their original condition," Neal said.

The company is weighing drilling beneath some streams, Neal added, but he said the technique typically takes longer, generates more noise and requires clearing more land.

The Federal Energy Regulatory Commission concluded that effects on surface stream crossings would be minimal, localized and temporary. The Army Corps of Engineers and the Maryland Department of the Environment, though, have the final say on Columbia's plans for crossing streams and wetlands. The agencies estimate construction would affect nearly 5.4 acres; less than an acre would be permanently lost, with mitigation proposed elsewhere.

Christopher Augsberger, spokesman for the corps' Baltimore District, said federal regulators still are evaluating the project and hope to reach a decision by spring.


"The concerns we've heard about drinking water, [and] concerns about the environment, are all on the table," he said.

But regulators must balance environmental and community concerns against economic needs, he said, including the cost to Columbia of requiring more expensive drilling techniques.

Kurt Kocher, spokesman for the Baltimore Department of Public Works, said city officials have reviewed the project plans and see no cause for concern that it would affect the water system.

"Keep in mind it's not on our property," said Kocher, noting it is county land upstream of the reservoir. However, he added, "We are going to make sure that we let every party involved know our intention to monitor and enforce any environmental impact to our reservoirs."