Coastal Commission to Vote on Major Changes to 101 Corridor between Eureka and Arcata

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A crumbling section of a century-old earthen dike along the defunct railroad right-of-way is all that stands between U.S. Highway 101 and Humboldt Bay, Oct. 28, 2015. Photo: Nancy Stephenson.

On August 7, the Coastal Commission will vote on Caltrans’ Eureka-Arcata 101 Corridor Safety Improvement Project, which includes an interchange at Indianola Cutoff, a left turn signal at Airport Drive, closure of all other medians to prevent cross-traffic turns, extended acceleration/deceleration lanes, and a new bridge over Jacoby Creek.

In a 2013 decision regarding the project, the Coastal Commission required the agency to plan or complete the Bay Trail, remove the billboards, plan for sea level rise (SLR), and develop a wetland mitigation plan. Six years later, Caltrans is back—without a sea level rise plan.

Bay Trail and Billboard Removal 

Thanks to the Coastal Commission, the Bay Trail has been partially completed, and many billboards removed. Unfortunately, Caltrans proposes to allow four billboards to remain along the bay side of the highway – including three billboards that stand in Humboldt Bay on public trust tidelands. These billboards are on private property, and the owner is not willing to sell them. Caltrans automatically renews permits for them every year, despite conflicting with state and local regulations. Caltrans also issues permits for vegetation removal around the billboards without any review of impacts to wetlands, since CBS Outdoor claims the signs are not in or near wetlands. We will continue to call for removal of the three billboards on public trust lands.

Sea Level Rise Planning Deferred to 2030

According to a Caltrans reported released in May, the section of highway from Eureka Slough to the former California Redwood Company mill is projected to be inundated by 2030. And the Coastal Commission’s staff report for the Aug. 7 hearing states that “significant portions of the highway corridor will be flooded with SLR as little as 1.6 feet, which could occur by 2040.” The entire 101 Corridor is in the 100-year flood zone, and is also vulnerable to tsunamis and soil liquefaction. These hazards will worsen as sea level rises, especially during major storms.

Despite these projections and the Coastal Commission‘s 2013 requirements, Caltrans has now agreed to develop a plan by 2030, or within a year of the first time the highway is flooded four times in a 12-month period. Of course, by the time that happens, it’ll be too late to begin the decades-long Caltrans planning process.

We’ve consistently raised concerns about Caltrans’ plan to construct a highway interchange in a low-lying area along Humboldt Bay without consideration of sea level rise. However, rather than spending the last 10 years planning for a long-term approach—such as a causeway to elevate the highway and allow the bay to expand beneath it—Caltrans plans to apply 20th century solutions to 21st century problems.

All that stands between 101 and Humboldt Bay is the 19th century system of unmaintained earthen dikes along the former rail corridor. According to Aldaron Laird’s 2013 shoreline vulnerability assessment, the majority of the dikes along the Corridor are moderately to highly vulnerable to breaching with current sea level.

Caltrans’ short-term sea level rise plan is to rebuild higher dikes. But the long-term impacts of “shoreline armoring” would be devastating to what little salt marsh remains around the bay— the marshes would basically drown unless there is a plan to allow them to migrate to higher ground as sea level rises. Salt marshes and eelgrass beds are critical habitat for many fish, shellfish, and migratory bird species, and are important for maintaining water quality.

Waiting to develop a long-term sea level rise plan until Highway 101 is closed by flooding four times in a year is unacceptable. Can you imagine Highway 101 traffic being rerouted onto Old Arcata Road/Myrtle Avenue and Highway 255 through Manila four times a year? Caltrans can do better than putting this off for another decade.

Make Your Voice Heard!

The Coastal Commission will give the public an opportunity to comment on the Eureka-Arcata 101 Corridor Safety Project on Wednesday, August 7 at 11:00 a.m. at the Wharfinger Building, 1 Marina Way, Eureka.

The agenda and information can be found at under the Meetings tab. Select Monthly Agenda, click on the Wednesday tab, and scroll down to number 11a Application No. 1-18-1078 (California Dept. of Transportation (Caltrans), Humboldt Co.)


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