Restoring Railroad Crossings for Chinook Salmon Recovery

However, such critical nearshore habitat has declined dramatically as development in the region and demand for freight transport has expanded.

Rail construction has divided coastal habitats from the nearshore, limiting the movement of fish, and disrupting natural habitat forming processes like the delivery of water, sediment, and wood. Region-wide development has contributed to a loss of ninety percent of tidal wetlands in Puget Sound. This has impacted sensitive species like juvenile Chinook salmon that utilize the Sounds’ natural estuaries in their migration to the Pacific Ocean.

Pictured: Railroad causeway in Bellingham Bay.

To address these ecological concerns, partners from the Tulalip Tribes, BNSF, Washington Department of Fish and Wildlife (WDFW), the Washington State Department of Ecology (Ecology), Snohomish County, and the South Puget Sound Salmon Enhancement Group advised on the identification and prioritization of coastal stream mouths (aka, pocket estuaries) and embayments (aka, nearshore habitat) restoration opportunities.

Pictured: BNSF railroad in the nearshore zone near Joint Base Lewis-McChord.

During migration, juvenile Chinook salmon often stay near the shoreline of Puget Sound as they leave large river systems before growing larger and eventually moving offshore ( Fresh 2006 ).

While in shallow nearshore habitats, they occupy small estuaries, called pocket estuaries which form at stream mouths or at coastal embayments ( Beamer et al. 2006 ). They have also been found to use the estuary and lower reaches of stream systems other than the ones they originate in ( Beamer et al. 2013 ).

Lower stream habitats and estuaries of coastal streams are important for Chinook salmon originating in other river systems, as well as for the coho and chum salmon who originate in the coastal streams and use them for spawning and rearing.

Photo credit: Rich Henderson, Skagit River Systems Cooperative

Railroad construction along Puget Sound first began in the 1870’s primarily to transport coal and other goods between Tacoma and Seattle, eventually  extending northward .

The railroad was first constructed as trestles which elevated the tracks above the shoreline. Over time, these trestles were filled and hardened to form a solid causeway.

Pictured: Historic image from Chuckanut Drive showing an elevated railroad trestle crossing Bellingham Bay.

Culverts were also installed to manage coastal stream flows, and for drainage purposes. These changes strengthened rail infrastructure, but consequently disrupted natural stream and estuary processes and cut off key routes for fish connectivity and migration.

Pictured (main): Railroad causeway entirely blocks portion of nearshore from Bellingham Bay. This creates an isolated embayment largely inaccessible to juvenile Chinook salmon.

The BNSF rail corridor encompasses 52 miles of rail which runs adjacent to the shoreline, and another 21 miles of track located within 200-feet of the shoreline.

Restoration will entail replacing existing railroad crossing structures with larger ones to aid fish passage and rearing habitat conditions. Planning for restoration began with:

1. Initiating a collaborative effort with BNSF, agencies, and restoration partners.
2. Inventorying of coastal stream mouths and embayments along the shoreline railroad and prioritize for restoration based on benefits to Chinook salmon.

Pictured: Nearshore Habitat in Woodway.

The project team evaluated a total of 196 stream crossings and 13 embayments that intersect with the railroad within 200 feet of the nearshore. The focus is primarily concentrated in three areas; between:

• Olympia and Tacoma,
• Seattle and Everett, and
• near Bellingham.

Streams were evaluated using field data and geospatial information and assigned a score based on their likelihood of use by juvenile Chinook salmon and the quality of upstream habitat.

Among the stream mouths, 17 sites were identified as the highest priority and 27 sites as a high priority. In total, 44 stream crossings were identified as priority restoration opportunities. In addition, seven embayments were identified as highest or high priorities for restoration.

Is a priority stream crossing near you? To navigate in this map, you can zoom in using the +/- buttons to the bottom right of the map frame. To pan around the map, use your mouse to click and drag to view the priority stream crossings.

Of the "highest" and "high priority" stream mouths and embayments, three stream mouths were selected for initial restoration planning to be completed during phase 2.

These sites included:

• Squalicum Creek near Bellingham,
• Japanese Gulch Creek near Mukilteo, and
• an unnamed creek at Joint Base Lewis-McChord (JBLM) near Steilacoom.

The project would replace three existing stream crossings with fish passable bridge spans using minimal in-stream supports and improve anadromous salmonid access to nearly 40 miles of stream habitat.

The existing stream channel would be expanded to create additional pocket estuary habitat.

The project would restore an existing stream which is currently confined to a pipe. The solution would include installing a fish passable culvert with direct connection to the restored pocket estuary and Possession Sound.

A fish-passable culvert would replace the current fish-barrier. This restoration work would open almost 1.5 miles of once-blocked salmon habitat.

At the three locations, site conditions were evaluated to inform restoration design and planning for construction. From this work, conceptual restoration designs were prepared.

Pictured: Existing conditions at the Squalicum Creek estuary site. Note the constrained flow from Squalicum Creek to Bellingham Bay.

This design concept depicts proposed restored conditions with three longer bridges and a wider estuary.

 The Meadowdale Beach and Estuary Restoration Project  in Snohomish County provides one example of nearshore restoration along an armored railroad embankment.

Prior to restoration, Lunds Gulch Creek passed under two BNSF railroad tracks via a 6-foot-wide box culvert. This culvert was too small to convey water and sediment and it impaired natural stream and shoreline processes.

In its place, restoration partners worked with BNSF to construct a new, 128-foot-long railroad bridge. In addition, partners also restored 1.3 acres of estuary habitat upstream of the crossing to restore productive rearing habitat for juvenile Chinook salmon.

The cooperation of Burlington Northern Railway (BNSF) was integral to the project’s success. This project represents a win-win through its multiple benefits to salmon restoration, beach access for park visitors, improved safety along the railroad, and enhanced park amenities and recreational experiences.