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Know the West

Peak and Ecological Flows in Oregon


As western states face proposals to divert and allocate the last available surface water – winter and wet season water – a debate is raging over how much of that water must be left instream to keep our rivers and their tributaries ecologically dynamic and alive.

The recognition that rivers need “peak flows” is a relatively new concept.  But experiments like the 1996 restoration water release on the Colorado River and the long fought for Trinity River Restoration Plan indicate that high or peak flows are necessary and can deliver benefits like renewed sandy beaches on the Colorado and restored salmon fisheries on the Trinity.

Trinity River restoration flows this spring. Once diverted to the Central Valley, 50 percent of Trinity River water is now released to the River from the dams above to mimic the pre-dam hydrograph

Scientists tell us that the best way to both use and preserve a stream is to mimic the natural hydrograph – including protecting minimum base flows and maximum peak flows. No matter which of several flow assessment methodologies is used, in the American West it typically takes 40 to 60 percent of total flow distributed in accordance with the natural hydrograph to keep a stream ecosystem functioning properly.

In most western river basins, however, agriculture consumes 80 to 90 percent of the dry season, or base flow. The discrepancy between what rivers need to remain dynamic and alive and what agriculture removes from those western rivers has fueled the West’s modern water wars. In each of the four great western river systems - the Columbia, the Klamath-Trinity, the Sacramento-San Joaquin and the Colorado – a major element of water conflict has been the need to reallocate dry season water from agriculture to in-stream use in order to increase minimum in-stream (ecological) flows.

Now the ground is shifting. The conflicts of tomorrow will focus on wet season (winter) water and peak flows. Some western water managers say more water can be removed from our rivers in winter and stored off stream for dry season use – usually by agriculture. But river scientists, fishermen, environmental activists and most tribes believe that would compromise peak flows needed to keep rivers alive and aquatic ecosystems healthy.

Fueled by new proposals to appropriate winter flows on the Columbia, the State or Oregon is an early battleground in the emerging struggle. During the Summer of 2009 the Oregon legislature passed HB 3369.  And while the legislation received scant media coverage it was immediately recognized by water lawyers as a game changer. The law requires that prior to approving state grants and loans for water infrastructure development,  officials must identify and reserve the “ecological” and “peak” flows needed to sustain the stream’s aquatic ecosystems. It gives a role in the review process to the Oregon Department of Environmental Quality and Department of Fish and Wildlife; previously reviewing and approving water projects was solely the province of the state’s  Water Resources Department – an agency which has traditionally favored water development.  Water projects in Oregon will now be judged on their “net environmental public benefit” including, for example, improvement or degradation of water quality.

The state’s anti-environmental right immediately denounced the legislation, declaring that Oregon would soon be experiencing California like water shortages as over-reaching state bureaucrats take farmers' water. SE Oregon state senator Doug Whitsett was one of the loudest critics.

Water Watch of Oregon – an state-wide group active in promoting the legislation -  vigorously defends it in appearances around the state and on the group’s web site.

The State of Oregon recently issued a white paper providing guidance on implementing HB 3369. The guidance is every bit as controversial as the original legislation. Oregon is also working on a State Water Strategy mandated by the legislation to address – among other things – climate change impacts to the state’s water supply.

I’ll bet you can guess how much Big Ag and the gaggle of Ag water lawyers like that one!

Essays in the Range blog are not written by the High Country News. The authors are solely responsible for the content.

Felice Pace has lived in the Klamath River Basin since 1975. For 15 years, he worked for and led the Klamath Forest Alliance as Program Coordinator, Executive Director and Program Director. He remains part of the Alliance’s Core Group, and now consults with environmental and indigenous organizations on fund raising and program development. He currently resides at Klamath Glen, near the mouth of the Klamath River.