Cascades to Olympics

Working to connect habitat in the Cascade Mountains to the Olympic Peninsula

Our Cascades to Olympics program works to restore habitat and improve wildlife connectivity between Washington’s Cascade Range and the Olympic Peninsula.

A map of our Cascades to Olympics program.           Click for a larger version!

The Olympic Peninsula contains the second largest mountain range in Washington and supports vast temperate rainforests and world-class biological diversity. As a peninsula, options for wildlife movements are limited by geography.

Existing connectivity pathways are threatened by growing development pressures, especially along Interstate 5. Increasing suburban sprawl, major flooding, and changing forestry, agricultural, recreational and economic dynamics add to this need for innovative conservation work.

As an initial step to maintain habitat connections, we are dovetailing off Chehalis Basin restoration strategies and engaging with local communities, tribes and regional stakeholders to provide means for wolves, elk, fishers, and other wildlife to safely pass I-5 and Highway 12. We are also continuing efforts to restore spotted owl and marbled murrelet habitat throughout southwest Washington and on the west side of the Olympic Peninsula.

July 2022: Southwest Connectivity Summit Resource Guide

News on Cascades to Olympics


Feasibility Study on Highway 12 with the Puyallup Tribe of Indians

Additional Resources and Links

The goals of the Cascades to Olympics connectivity program over the life of our current 2017-2022 Strategic Plan are to:

  1. Maximize conservation outcomes for habitat, wildlife, and fish through the Chehalis Basin Strategy,
  2. Identify potential locations to implement wildlife crossing infrastructure on I-5 and Highway 12,
  3. Invest early in the southern linkage to build relationships for later efforts, including habitat restoration and increased wildlife connectivity at a landscape scale.

This program involves a region of Washington where we have a long history of protecting old-growth forests, pioneering forest restoration collaboratives, and reintroducing fishers, as well as a recent focus on conserving forest habitat for spotted owls, marbled murrelets, and other species on state trust lands and private forest lands.

Our Cascades to Olympics program will improve habitat connectivity for populations of reintroduced fishers in the South Cascades and Olympic Peninsula. Photo: Paul Bannick

The Cascades to Olympics program also builds off a successful model for maintaining connectivity in the Central Cascades by protecting habitat linkages through The Cascades Conservation Partnership, establishing wildlife crossings across I-90 through our I-90 Wildlife Corridor Campaign, and forest and aquatic restoration actions through our Central Cascades Watersheds Restoration program.

The Cascades to Olympics program will similarly build the social and physical infrastructure for wildlife crossings in south-central and southwest Washington. In addition, we’ll work off of our years of experience reconnecting and restoring fragmented habitats to strengthen wildlife corridors and breeding habitats for long-term genetic and demographic connectivity essential to ensure healthy wildlife populations over the long term. We’ll support permanent watershed and wildlands protections in the program area, including the Wild Olympics proposal.

By scientifically identifying pinch points and current safe passages for wildlife, we have prioritized a focus on the Chehalis Basin. Engaging in the Chehalis Basin Strategy provides us with the opportunity to integrate infrastructure and habitat protection and restoration focused on terrestrial wildlife moving through this corridor in the Chehalis management plan.

A secondary priority has also been identified further south in Lewis County from west of Mount St. Helens to the Willapa Hills. Working with local communities, tribes, agriculture, forestry and other interests will be critical for success in this landscape, and Conservation Northwest is well-poised for such an approach given our successes working with stakeholders on conservation outcomes in other areas.

Program Context

An existing structure under I-5 at Newaukum River. Our Cascades to Olympics program seeks to enhance structures like these to better serve as wildlife crossings. Photo: Brian Stewart

The program geography stretches from Mount Rainier to the southern end of the Cascades in Washington at the Columbia River Gorge, west across I-5 and the Willapa Hills to Willapa Bay and then north past Grays Harbor to the Olympic National Forest, and east around the south Puget Sound back to the Cascades. This area contains the Chehalis Basin (including key tributaries such as the Satsop, Skookumchuck and Newaukum rivers), the lower Cowlitz and Toutle basins, and many other rivers.

Download our program description or program map as a PDF. A more detailed map showing habitat naturalness connectivity is available below (larger version). Our program map summarizes this data, showing general connectivity corridors. 

Our strategy involves building legislative and community support including working with the Washington State Department of Transportation (WSDOT) to establish crossing structures, protecting wildlife and bird breeding and foraging habitat in key landscapes and linkage areas involving both state and private lands, incentivizing dispersal habitat management where appropriate to ensure safe passage for wildlife.

We have two initial focus areas:

  1. Landscape-scale habitat restoration and wildlife connectivity efforts through the Chehalis Basin Strategy’s Aquatic Species Restoration Plan (ASRP), and
  2. Efforts to restore forest habitat for spotted owls, marbled murrelets, and other species through partnerships with DNR, WDFW, and private landowners.
The Upper Chehalis River. We’re dovetailing off Chehalis Basin restoration strategies to provide means for wolves, elk, fishers and other wildlife to safely pass I-5 and Highway 12. Photo: Steelhead and Salmon Conservation Society

The ASRP is a response to severe flooding of the Chehalis River, causing closures on I-5 and devastation to nearby communities. In addition, human development has degraded the habitat for salmon and other fish and wildlife. With climate change expected to exacerbate the current situation, the ASRP is designed to make communities and habitats in the Chehalis Basin more resilient. This plan parallels a proposal to reduce flood damage by building a dam on the upper Chehalis River.

While our principle contribution will be terrestrial wildlife connectivity and habitat restoration, we’ll also collaborate around ongoing fish and aquatic species recovery. We will engage with the Office of Chehalis Basin, administered by the Washington Department of Ecology in coordination with the Confederated Tribes of the Chehalis Reservation, the Quinault Indian Nation and the Washington Department of Fish and Wildlife, the Chehalis River Alliance, and other partners.

In addition to working in the Chehalis Basin, the Cascades to Olympics program is also building on planning efforts for spotted owl and marbled murrelet habitat conservation and connectivity undertaken by the Washington Department of Natural Resources. DNR’s Northern Spotted Owl Implementation Team commissioned a group of modeling experts to identify key forest locations in southwest Washington that would allow for improved residence and long-term movements of owls between the Cascade mountains and the Olympic Peninsula. Many of these locations are on private and State DNR lands. We have been working with stakeholders to create funding mechanisms to acquire future habitat areas identified by the modeling team. In addition, we have been working with DNR, Washington Department of Fish and Wildlife and forest landowners on creating regulatory certainty through a statewide federal Safe Harbor agreement for spotted owls. These efforts also benefit other species, from Roosevelt elk and fishers to cougars and salmon.

Through our Cascades to Olympics program, we’re working to secure more current and future murrelet habitat. Photo: Rick Bowers

For marbled murrelets, we are working to secure more current and future murrelet habitat in southwest Washington and on the Olympic Peninsula to secure long-term nesting sites for the species. This work includes creating funding mechanisms as above for spotted owls, solving revenue issues for county and school trust beneficiaries, and going to court to get a more accurate interpretation of the State’s Trust mandate to allow DNR more flexibility to protect endangered species.

Securing and restoring habitat for old forest-dependent species in southwest Washington and on the Olympic Peninsula will contribute to the health of forest ecosystems in the region and allow for hundreds of other species to maintain a foothold and adapt to climate change over time.

Program Priorities

  1. Serve as a lead voice for terrestrial species conservation in the Chehalis Basin Strategy and Aquatic Species Restoration Plan, advocating for the consideration of future effects of climate change and its impact on wildlife populations.
  2. Identify current migration pathways and existing infrastructure on Highway 12 through modeling and wildlife monitoring to locate pinch points for enhancing wildlife movement or implementing new crossings.
  3. Advocate for enhancements such as wildlife fencing and habitat restoration to existing wildlife pathways underneath I-5, including north of the Toutle River and the Toutle River crossing, south of Prairie Creek and north of Skookumchuck, and the Newaukum River.
  4. Encourage flood damage reduction strategies to prioritize habitat restoration, growth management planning and improvements to existing land-use patterns as an alternative to a dam on the Chehalis River.
  5. Engage with a diverse set of local stakeholders including landowners, tribes and state agencies to implement strategies for habitat restoration and wildlife corridor protection.
  6. Secure funding for forest habitat acquisition and restoration in the Cascades to Olympics program landscape.
  7. Complete negotiations on the spotted owl Safe Harbor Agreement and additional marbled murrelet habitat protections on DNR lands beyond their Habitat Conservation Plan amendment.
Learn more in this blog on our Cascades to Olympics Connectivity report!
A rainforest scene in Olympic National Park. We’re working to improve connectivity and restore habitat between the Cascade Mountains and the Olympic Peninsula. Photo: Chase Gunnell