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The Nature Conservancy in Oregon Home Contact Places We Protect Field Trips & Events Press Releases Volunteer Ways of Giving |
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Mark Stern is the director of the Conservancy's Klamath Basin Conservation Area. He leads the organization's efforts in southwest Oregon and oversees the restoration and management at the Williamson River Delta Preserve and the 30,000-acre Sycan Marsh Preserve. Stern also represents the Conservancy on the Upper Klamath Basin Working Group, where he has served as co-chair since 2002. In 2002, Stern received the "Oregon Wildlife Society Career Achievement Award" for his work to protect snowy plovers. Get Involved |
By Lauren Miura
The Williamson River in southwestern Oregon was dredged, drained and generally disturbed back in the 1940s and 1950s. Farming prospered along the river, but wildlife — especially two species of native fish — suffered due to the loss of wetland habitat.
So now — more than 50 years later — can conservationists bring back the wetlands that once dominated the Williamson River Delta?
Nature.org caught up with Mark Stern, director of The Nature Conservancy’s Klamath Basin program, to talk about the Conservancy’s restoration plan for the river delta and explain how explosives may bring back two species of fish from the brink.
Nature.org: Conservationists aren’t exactly known for their use of explosives. Why is the Conservancy blowing up a bunch of levees?
Mark Stern: The recipe for restoring wetlands has one main step: Add water.
The restoration project at the Williamson River Delta Preserve — one of the largest projects of its kind ever in Oregon — involves moving more than 2 million cubic yards of soil that is packed into large levees.
But the problem is that the levees act as an unnatural barrier between the wetlands and Upper Klamath and Agency Lakes, creating unhealthy conditions for fish like the endangered shortnose sucker and Lost River sucker.
We’ve determined that the best way to remove the levees quickly and safely is to use about 200,000 pounds of explosives to destroy two miles of levees in a matter of minutes. Once the levees are breached, waters from the Upper Klamath and Agency Lakes will immediately inundate the site, covering about 2,500 to 3,000 acres with water — as much as six feet in some places.
As you might imagine, there are a lot of safety and security procedures that are mandatory for this technique. We're working with a team of engineers — including professionals who are members of the International Society of Explosive Engineers — to insure that all protocols are followed.
Nature.org: Is this a common practice in conservation?
Mark Stern: Restoring wetlands is occurring throughout all regions of the world, and I’m sure that many innovative techniques are used. While I imagine explosives are used in some situations, I think it’s safe to say there haven’t been many projects where explosives have been used at this scale.
Nature.org: Why were the levees created in the first place?
Mark Stern: Agriculture. The entire 7,000-acre Williamson River Delta was once vast marsh wetlands along the edge of the Upper Klamath Lake, with the river meandering through the delta.
Starting in the 1940s, two brothers converted the wetlands into farm fields. They dredged up sediment on the bottom of the lake to build a 22-mile-long levee around the entire perimeter of the marsh and along the river. The river was straightened and became more of a canal than a free-flowing river.
The conversion of these wetlands to farm land was a pretty amazing engineering feat, and this land became one of the most productive farm areas in the Klamath Basin for half a century. But over the last 10 years, the Conservancy has been working with partners to begin the gradual process of restoring the wetlands.
Nature.org: What will the preserve look like after the levees are breached?
Mark Stern: Over the next few years, marsh wetlands will re-emerge in the flooded acres. Along the Williamson River, there will be a strip of lush riparian habitat up to where it joins Upper Klamath Lake. The remaining portions of the levees adjacent to the lake will be reshaped, and wetland vegetation and willows will start to grow there.
Nature.org: You mentioned that the two endangered species — the shortnose sucker and the Lost River sucker — will benefit from the wetlands restoration project. How so?
Mark Stern: Adult suckers live primarily in Upper Klamath Lake for most of the year — but they migrate upstream in early spring to spawn. Before the area was turned into farmland, larval fish would flow downstream and hang out in the marshlands at the mouth of the river until they were large enough to enter the lake.
When this protected rearing habitat disappeared, the larval fish began emptying directly into the lake. Without time to gain size and strength in a safe environment, the young fish had a hard time surviving. So this project will provide much-needed marsh habitat for young fish.
It’s important to recognize that these are long-lived species. Most don’t begin to spawn until five or six years of age, and adults may live to 40 years. It will take time to fully recover these species, but we are encouraged by the results we’ve seen so far.
And the restored wetlands will also be great habitat for birds and other wildlife and will help improve water quality in Upper Klamath Lake.
Nature.org: So what’s next for the restoration project?
Mark Stern: Based on results from this year’s work, we will continue our efforts on the south half of the delta, reconnecting an additional 2,000 acres of historic wetlands to Upper Klamath by 2009.
The next big effort in the Upper Klamath Basin will be the anticipated removal of the Chiloquin Dam, which is 13 miles upstream from the Williamson River Delta. The Modoc Point Irrigation District, which presently receives irrigation water from the dam, is building a pump station that will render the dam unnecessary.
If all goes as planned, the dam itself will be removed in the fall of 2008. Once removed, suckers migrating upstream to spawn will have access to more than 60 additional miles of riparian habitat.
Lauren Miura is a senior writer at The Nature Conservancy.
Nature picture credits: Photo © Kenneth Popper/TNC (Williamson River Delta); © Jen Newlin Bell (Mark Stern); © TNC (Klamath Basin map); © Tuppel Ansel Blake (Lost River sucker)
