Enclosed pipes are replacing most of the open canals
By Ann McCreary
Just a little over a year after the project broke ground, the Methow Valley Irrigation District’s restructured delivery system is nearing completion and will be operating by the next irrigation season.
“We will be able to deliver water through the all-new system by May 1, 2016,” said Greg Knott, project manager. “We’re still on schedule and within budget.”
The $10 million “Instream Flow Improvement Project” is installing enclosed pipes to replace most of MVID’s two open canals that ran along the west and east sides of the Methow River.
Additionally, about 80 MVID members who are not connected to the piped system have dug wells or upgraded existing wells to irrigate their property. Only a handful of the well conversions are left to complete, said Roger Rowatt, construction manager for the project.
Underground pipes were installed last summer to connect MVID customers within Twisp town limits to the east side piped system, providing irrigation for the first time to some MVID members in town.
The objective of the improvement project is to reduce the amount of water withdrawn by MVID to serve its approximately 270 customers, leaving more water in the Twisp and Methow rivers for fish habitat.
Work on the project in recent months has focused on the district’s west side canal, which has been fed by water diverted from the Twisp River about 3 miles upstream from Lookout Mountain.
That diversion has been the principal cause of years of regulatory and legal battles between MVID and state and federal environmental agencies, which said taking water from the Twisp River damaged habitat for endangered fish.
A separate project to restore the river and riparian areas around now defunct irrigation diversion is being conducted by Methow Salmon Recovery Foundation.
When the west side ditch was shut down for the season earlier this month, crews with Bianchi Construction of Mount Vernon began installing pipe along a 1.8-mile stretch of the canal route. When complete, the pressurized pipe will deliver water pumped from four wells dug in an orchard behind Hank’s Harvest Foods.
The piped section will deliver water to about 76 customers, extending south from Lookout Mountain Road to just north of the beaver ponds on the Twisp-Carlton Road.
With the canal enclosed, trees deprived of water will need to be cut down and removed so they don’t die and pose a risk to people and property, Knott said. The same process occurred earlier this year after 4.5 miles of the east side canal, which withdraws water from the Methow River, were enclosed.
Most conifers along the ditch will be allowed to stay in place, but deciduous trees like cottonwoods that are more likely to die will need to be removed, unless landowners sign a waiver accepting liability for possible damage, Knott said.
Property owners along the canal route have been notified about the tree removal. Trees will be cleared along a 25-foot-wide swath on either side of the ditch from Twisp to near the Golden Doe Ranch in Carlton.
Most of the logging will take place in winter after the ground is frozen to minimize damage to the soil, Knott said. Branches and other debris left from the logging will be removed next spring, he said.
Work on installing the four wells behind the grocery store is nearly complete and crews are preparing to connect them to the pressurized pipe.
“We’ll charge the lines for the first time next spring,” Knott said.
Converting to wells
As a result of the changes to the west canal system, 82 customers — the majority of them at the end of the former west canal route along the Twisp-Carlton Road — have converted to wells for irrigation.
Rowatt said about 20 property owners required pump upgrades for existing wells. Only about seven properties hit dry holes and required digging more than one hole to find water. The wells and pump upgrades were funded through the project.
“What they’re getting for the first time, especially the on the west side, is really reliable water,” because often water flowing down the ditch didn’t reach the users at the end, Knott said.
Each well system was designed to produce enough water to serve the acres included in the MVID assessment, Rowatt said.
The state Department of Ecology, in permitting MVID to drill the individual wells, required that each well be metered, read weekly, and reported to Ecology annually, Knott said.
The metering not only tracks the exact water use to make sure it is within the amount authorized by Ecology, but also is likely to improve water conservation, Knott and Rowatt said.
“Maybe you decide the grass grows just as well with a little less watering,” Rowatt said.
“Or you look at your electrical bills [or the well pumps] and say, ‘Maybe I’ll water at night,’ or ‘Maybe I won’t water when it’s raining,’” Knott said. “There should be a significant reduction in water use.”
The $10 million instream flow improvement project has resulted in an irrigation delivery system that is “about the size of a small town water system,” Knott said.
MVID “wont need a ditch walker, they’ll need a technician,” he said. “It’s a complicated system. There are upwards of 200 valves in the new system.”
The project is funded through about $6 million from the Ecology’s Office of Columbia River, and approximately $4 million from habitat mitigation funding from the Chelan-Douglas County and Grant County Public Utility Districts.