State works to mitigate flood damage, restore fish habitats in Chehalis River basin
Inslee receives update from Chehalis Basin Work Group
In the decade following the devastating Chehalis River flood, state and local leaders have put strategies in place to prevent damage from floods in the state’s second-largest river drainage basin. And they are planning more.
The 2007 flood closed Interstate 5 at Chehalis for four days. The rising waters snarled traffic locally and regionally, killed livestock, destroyed buildings and displaced families and businesses. As the community repaired the damage and cleaned up the mess, officials began preparing for future floods.
They did not have to wait long, with floods hitting again in 2009, closing I-5 for two days and causing more damage.
In 2011, the Washington Legislature commissioned a report on projects that could help the state’s flood-prone areas. The next year, then-Gov. Chris Gregoire formed the Chehalis Basin Work Group, composed of local elected officials, citizens and tribal leaders, to recommend actions to mitigate flood damage and explore options for restoring fish habitat.
During the past several years, millions of dollars have been invested in the effort. In the state’s 2013–15 and the 2015–17 budgets, lawmakers dedicated a combined $78 million to gathering information, studying options and acting immediately on flood mitigation and fishery projects. As legislators work on a compromise 2017–19 budget, they are considering a new state investment of up to $50 million.
This year will bring even more changes. Starting in July, the work group will become an official state board — the Chehalis Board — overseen by the state Department of Ecology. Gov. Jay Inslee is responsible for two appointments to the board, while the local Chehalis River Basin Flood Authority appoints three members and two tribal governments — the Confederated Tribes of the Chehalis and the Quinalt Indian Nation — each appoint one.
Inslee has appointed Steve Malloch and J. Vander Stoep, two work group members. Malloch said the flooding problems in the Chehalis River basin are not easy to solve. They involve competing interests, including the safety and property of local residents and tribal fishing rights.
Fish harvest in the Chehalis River basin has been limited by poor runs over the last 30 years and aquatic species habitat productivity has been degraded by up to 87 percent. In recent years, summers have become drier with lower stream flows and warmer water temperatures — and these conditions are predicted to get worse.
“Local communities suffered from devastating floods over the course of the last 10 years and they want to have their risk of flooding reduced,” he said. At the same time, two tribes that fish from the basin, the Confederated Tribes of the Chehalis Reservation and Quinault Indian Nation, have seen “their ability to engage in their fishing activities reduced. We’re really wresting with: How do you address these two prime needs for the basin of dealing with flood risk management as well as improving the fisheries?”
Projects in the works
Despite challenges, several changes have been made to reduce harm from flooding and improve aquatic-species habitat, with the goal of restoring more than 100 miles of river habitat.
On Thursday, Inslee toured parts of the Chehalis River Basin and met with some of the people working on the problem. He took a similar tour two years ago.
So far, regional improvements have included floodwalls, fish habitat restoration and flood plain reconnections in several communities. More projects are under consideration, including:
- Building a dam, reservoir and fish passage system on the river.
- Rebuilding the capacity of the basin to naturally store floodwaters by restoring the connection between river channels and floodplains while raising parts of the riverbed.
- Raising the levee at the Chehalis-Centralia Municipal Airport.
- Building flood walls along a 5-mile stretch of I-5 through Centralia and Chehalis.
- Buying flood-prone property from willing owners.
- Repairing fish culverts and eliminating fish passage barriers.
- Protecting habitat through conservation easements and land acquisition.
- Sealing building walls, doors and other openings to keep floodwaters out.
- Using inflatable, temporary barriers around buildings during a flood.
- Installing flood vents in buildings that allow water to flow through parts of the structure.
- Adding native plants to the Chehalis River and key tributaries.
- Reconnecting floodplains and off-channel habitat in strategic areas.
Striking a balance
When it comes to the question of whether to build a dam or pursue an alternative, such as improving the capacity of the river basin to naturally store floodwaters, the state is nearing completion of an environmental impact statement that will allow the Chehalis Board to weigh the options.
“One of the options on the table is a dam in the upper reaches of the Chehalis River,” Malloch said. “Dams are not the kind of approach that most environmentalists are interested in and can have significant fishery impacts. If a dam is on the table, we have to look at it really hard and make sure that all of the questions that might be raised about it get answered.”
One of those questions is how to ensure the health of salmon and other aquatic species.
Efforts to restore habitat for aquatic species go beyond simply mitigating the effects of a dam. A major goal for the work group is to significantly restore fish populations, including taking a proactive approach to protecting salmon.
“The goal is to have a robust fishery in the basin,” Malloch said. “We’ve got to figure out how to make sure all of the interests get addressed.”
Malloch said Washington will find itself grappling more often with water supply and flood issues as its population grows and climate change impacts increase.
Floods have become more destructive through the years due in part to climate change. Winter storms that are expected to get worse will magnify problems. Drier and hotter summers, lower summer stream flows and higher water temperatures threaten salmon. The risk of what used to be called a “100-year flood” — floods that previously had a 1 percent chance of occurring in any given year — has increased 33 percent in the past three decades, according to information from the Chehalis Basin Work Group.
Solving these problems will require conflicting interest groups to come together as they are in the Chehalis River basin, Malloch said.
Chehalis Board appointee Vander Stoep called the progress that’s been made in the basin over the past five years “historic.”
“For 100 years, there was failure on the flood issue and the fish issue,” Vander Stoep said, adding that despite numerous studies, no major action was taken and it was hard for everyone to come together.
But following the 2007 and 2009 flood, he said, “what has emerged is an understanding that you’re not just going to make progress on the flood issue. You’re not just going to make progress on the fish issue. You’re going to address them both together.”