Bend water project critics release dire watershed study

Flows in the headwaters of Tumalo Creek will be severely reduced in the coming decades, according to a new study released Tuesday by Central Oregon LandWatch, which has been fighting the city of Bend for several years to stop its water withdrawals from Bridge Creek.

The study, “Climate Change Impacts on Stream Flows, Upper Deschutes Basin,” indicates that a warming climate will impact groundwater discharge to streams, decreasing the flows that currently contribute to Bend’s water supply, according to the group.

The study was commissioned by Central Oregon LandWatch and conducted by the hydrogeologic consulting firm Mark Yinger and Associates.

They used modeling tools to simulate climate change, aquifer recharge, and groundwater flux to and from streams in the basin.

The models indicate that by mid-century, there will be a significant reduction in the volume of water in Tumalo Creek above Tumalo Falls during summer and fall months, and that in the future there may be little or no water for the city of Bend to divert in warmer months.

The study concludes that, “because of the significant impacts of climate change on the upper portion of Tumalo Creek, from which the City of Bend gets its surface water, the City’s planned water withdrawals from Tumalo Creek may not be sustainable if flows over Tumalo Falls are to be protected.”

The group has claimed the project to replace aging city water pipelines to Bridge Creek, a tributary of Tumalo Creek, is wasteful and harmful to the waterways’ habitat. They have argued the city can give up its rights to surface water and rely solely on pumping from ample groundwater supplies in the future.

“Fish, wildlife, municipal water providers, irrigators, and recreationists all rely on these streamflows,” said Paul Dewey, a land-use attorney and executive director of COLW.

“The findings from this study confirm that the upper reaches of the Tumalo basin will be profoundly affected by climate change and reinforce the importance of working to conserve water now,” he said.

The model shows that reductions in stream flow will occur primarily in the higher elevation reaches of tributaries to the Deschutes River.

They indicate that by the year 2039, the average June base flow for Tumalo Creek will decline by 61 percent, compared to a 2008 baseline. The flows will decline further by the year 2060, to 86 percent less than current flows.

The study also modeled future impacts to Whychus Creek, whose headwaters are at a lower elevation than Tumalo Creek. Results show a consistent 5-10 percent reduction of flow throughout the year, not just in the warmer months.

While the results of the study show the long-term impacts of climate change on Central Oregon’s water resources, the group said, its effects are being felt now.

Many scientists say this year’s warmer weather and reduced snowpack are a precursor of what’s to come, including water shortage problems, drought and more frequent wildfires, Dewey said.

“While we can’t make it snow, we can take steps that will mitigate the risk to our critical water resources,” said Dewey. “It is imperative that we make the right decisions today to make sure there is an adequate water supply in the future.”

City Councilor Sally Russell said she was glad LandWatch did the study, which points to broader issues of climate change the city and all communities will face, if the water aquifer drops and a drought cycle hitting California and the Northwest lingers.

But in some aspects, she said, “The consensus is, there is no consensus. There are certainly a lot of different scenarios that can play out, with different end results. It’s very likely in the Northwest, we will remain a lot wetter than other areas in the world.”

“The council has, without a doubt, stated in recent council goals that restoring Tumalo Creek is a priority.” she said. “Central Oregon LandWatch and the (U.S.) Ninth Circuit (Court of Appeals) have expressed interest in engaging all the parties in mediation.

“The community deserves to try to find some middle ground. I would love to be spending money on restoring Tumalo Creek, and not legal fees. Sooner or later, that’s my wish.”

Learn more, with a link to the full study, at http://www.centraloregonlandwatch.org/ .

The city’s page on its pipeline replacement project is at: http://bendoregon.gov/index.aspx?page=155