BILLINGS, Mont. - Federal lawmakers are seeking to lift restrictions on hydropower development so more local irrigation districts could use water flowing through government-sponsored agricultural canals and pipelines to generate electricity.

Proponents say hundreds of irrigation systems, the bulk of them in the Great Plains and Rocky Mountains, would be able to pursue small power projects under proposals from Western lawmakers.

The measures seek to change laws that block or restrict hydropower projects on systems built by the government after 1939, as part of efforts to help people hard-hit by drought at the time of the Dust Bowl. They would promote projects of five megawatts or less that could generate money and work for irrigation districts.

As costs mount to repair aging water supply networks and make them more efficient in the face of recurring drought, irrigation district managers said the electricity from small hydropower projects could be sold to provide money to help cover their expenses.

"We have the ability for more power generation but are being held back," said Gary Mancos, superintendent for the Mancos Water Conservancy District in southwestern Colorado.

A hydropower bill from Colorado Republican Rep. Scott Tipton, which would cover 373 Bureau of Reclamation canals and water conduits, passed the House last month with broad support from both parties. A similar measure from Wyoming Republican Sen. John Barrasso has cleared the committee level in the Senate and is awaiting a floor vote.

Another House bill, from Republican Rep. Steve Daines of Montana, targets a dozen waterways not fully covered by the other measures. It had an initial hearing last week and could come up for a committee-level vote over the summer.

Daines' bill includes water supply projects in Montana, Utah, Idaho, South Dakota, Colorado, Nebraska and Texas.

The first-term Republican said allowing hydropower development on those irrigation systems would help promote a renewable energy resource at no cost to taxpayers.

"Besides water, our rancher and farmers in Montana need power. These same irrigation projects have the potential to power homes and businesses," Daines said. "The federal government stands in the way, as current law prohibits non-federal developers from taking full advantage" of hydropower from irrigation systems.

Bruce Farling with Montana Trout Unlimited said he's reviewed the proposals and did not have any immediate concerns that they could hurt fisheries. For projects limited solely to irrigation systems, "fish shouldn't be there in the first place," he said.

But he added that future hydropower initiatives would have to be looked at individually to make sure there were no problems like the possibility of fish getting trapped in a canal.

The measures before Congress also have received qualified support from the Bureau of Reclamation, which in recent years has sought to expand its role as the second largest producer of hydropower in the country behind the U.S. Army Corps of Engineers

The agency said in a report last year that its canals combined have the potential to generate more than 100 megawatts of electricity - enough to power tens of thousands of homes.

Bureau of Reclamation Senior Advisor Robert Quint said during recent testimony before the House Natural Resources Committee that the agency wants to make sure it can review potential environmental impacts if warranted for any hydropower project proposed.

In eastern Montana, Michael Carlson with the Buffalo Rapids Irrigation District in Glendive said he's eager to try out the concept. He's been investigating options to put small electricity-generating turbines directly into the pipelines Buffalo Rapids uses to transport water from canals fed by the Yellowstone River to farmers' fields.

For now, it is too early to say how much power could be generated or if it would even be economically feasible, Carlson said. But he said the proposals before Congress would let him find out.

"It's like the first stages when they started to develop wind farms," he said. "We're just capturing the water pressure and seeing if it will make electricity. It's a pretty simple concept."