Digging rodents threaten canal safety in Central Oregon

Ground squirrels, rock chucks keep irrigation managers busy

Published Apr 11, 2017 at 03:01AM

Drive along the Pilot Butte Canal in Redmond in the spring and you’ll see ground squirrels scurry frantically back and forth across the road. Chubby rock chucks sprint from rock to rock.

Both types of rodents pop up, run around and then disappear into burrows. The underground dens and tunnels provide protection from predators and the elements, but they also risk causing millions of dollars in damage to urban developments.

Rodents living along canals pose a huge threat, irrigation district officials say. Their tunnels can cause a breach of the canal, sending surging water through neighborhoods and other urban developments. As a result, keeping tabs on the furry critters and the integrity of the canal is a full-time job for eight “ditch riders” employed by the Central Oregon Irrigation District.

Larry Roofner, operations manager for COID, drove along a portion of the canal sitting just above the soon-to-be Triple Ridge housing development Monday. This is one of the higher-risk areas and is monitored daily.

“We have concern there,” Roofner said. “It carries about 300 cubic feet of water (per second). If that were to breach, there could be damage to what was previously irrigated land but is now a new subdivision and Ridgeview (High) School.”

To try and prevent a breach, ditch riders keep high-powered pellet guns in their vehicles and will shoot rodents when possible. In addition, Roofner said the district contracts with exterminators to kill burrowers, usually through trapping, though he said they can use whatever means they deem necessary.

The district is tasked with maintaining roughly 450 miles of canals throughout the region, and rodent abatement is a part of that. However, not all see it that way.

Oakley Taylor, 61, lives just outside city limits to the southeast of Bend. Last week, she was told by a neighbor that the district was shooting river otters in the canal near her house with a rifle. It turned out to be muskrats being shot with a pellet gun, but nonetheless Taylor was upset. She called the district, as well as the Deschutes County Sheriff’s Office.

“They just wanted to come out to the neighborhood and shoot these muskrats or otters or whatever,” Taylor said.

Roofner said he talked with Taylor, explaining that his employees were not killing the animals for sport — as well as the devastation a breach could cause.

Taylor said she appreciated the conversation but thinks the district should make more of an effort to inform people living near the canals of the abatement and doesn’t see why the rodents need to be killed.

“It’s sad, and I guess that is going to be more of the clash between animals and humans, and that isn’t going to go away,” she said.

Taylor is right. When the district’s two canals were first built, the areas surrounding them were far more rural. But now in many places, such as Triple Ridge, they sit above residential areas, and a breach can cause serious damage to hundreds of homes. And the rodents can be ruthless; Roofner recalled digging up a area to find ground squirrels had “honey-combed” the earth on the edge of the canal.

But a more wildlife-friendly solution appears to be on its way. ShanRae Hawkins, spokesperson for the district, said it is working toward piping irrigation water rather than sending it down in open ditches. Hawkins said so far the district is in the engineering planning phase, and there is no timeline for piping. It would be a more efficient way to transport water and would also stop rodents from burrowing into the water supply, which becomes more important as urban density around the canals increases, as it has around Reed Market Road in Bend. A breach in that area, where the water flows at 500 cfs, would be devastating, Roofner said.

“We would have water running down Third Street,” he said.

— Reporter: 541-383-0376, awieber@bendbulletin.com