Travel along the First Street River Trail in Bend, and you are walking on water.

Actually, you are walking on dirt covering a steel pipe lying in the middle of what used to be part of the Bend Feed Canal, which carries water from the Deschutes River to ranchers and farmers.

The pipe belongs to the Tumalo Irrigation District. The project – putting the open canal underground – is one of many undertaken in a large-scale piping project for the Bend Feed and Tumalo Feed canals.

The district has conserved about 6,263 acre-feet of water with its piping project, said Scott McCaulou of the Deschutes Resources Conservancy, which is partially paying for the piping project. That’s enough water to fill Big Lake near the Hoodoo ski area almost two times.

With a price tag reaching past $5 million, that averages out to about $790 per acre foot. An acre foot of water equals the amount of water necessary to cover an acre of land a foot deep.

Elmer McDaniels, manager of the Tumalo Irrigation District, said the cost may seem high, but it will pay off by saving more water and creating a more efficient irrigation system that requires less maintenance.

”This is pretty much a one-time cost,” he said.

As state officials draft rules to govern future water use in Central Oregon, water conservation has launched to the forefront of debates about growth and environmental preservation. Canal piping is one way to keep more water in rivers and their tributaries.

However, piping keeps irrigated water from seeping through the earth and percolating into an underground aquifer. That aquifer joins the surface water of the Deschutes at the Pelton-Round Butte dam complex.

If the aquifer levels drop, they could also lower river levels at the dams, which would violate the state’s wild and scenic river designation on the lower Deschutes.

However, most conservationists say they support canal piping, as long as the project is not used to offset new groundwater use, a process known as mitigation. State officials are presently deciding if canal piping can count as mitigation.

Canals leak about 50 percent of the water passing through, and before the district began piping, managers at Tumalo Irrigation believed they needed to divert more water from streams to water their fields, said Bob Varco of the district. However, they found additional water by piping.

”Before, we thought we didn’t have enough water, and we were looking to get more water rights,” Varco said. ”We do have enough water; we just need to use it well.”

Piping also improves stream flows in Tumalo Creek because irrigators do not divert as much water as they used to, McDaniels said.

Specifically, Tumalo Irrigation District has guaranteed to leave at least 5.8 cubic feet per second (CFS) in Tumalo Creek. One cfs equals 448 gallons per minute.

Historically, Tumalo Creek in Shevlin Park dried up to a near trickle when Tumalo Irrigation District used to divert water through Upper Columbia Southern Canal, which is no longer used, McDaniels said.

Eventually, officials hope to add more water in Tumalo Creek, for a total of 17.1 cfs of guaranteed instream water, McDaniels said.

Tumalo Irrigation District gets water from Tumalo Creek and from water stored at Crescent Lake and delivered via the Deschutes.

Tumalo Irrigation District board member Jim Schlueter said that as the Central Oregon population grows, officials may one day limit the amount of water that can be diverted from rivers. If that happens, he said Tumalo Irrigation District will be prepared and will have enough water because of its piping projects.

”Eventually, there will be limits on water use,” he said. ”If you have a system that leaks, you’ll be in trouble. We’re not going to be in that position.”

Saving water also adds water to rivers and creeks that traditionally dry up every summer because of irrigation, McDaniels said. By helping ”rewater” certain stretches, irrigators can improve fish and wildlife habitat.

Although Tumalo is leading the way, Swalley, North Unit and other irrigation districts are also piping canals.

For more information about canal piping on Tumalo Irrigation District, visit www.tumalo.org.

Rachel Odell can be reached at 541-617-7811 or rodell@bendbulletin.com