Last Chance Grade Project Update

By
Wednesday, May 16th, 2018

The Redwood Highway, also known as Highway 101, is the main north-south arterial connection for North Coast residents and visitors alike. “Last Chance Grade” is a stretch of Highway 101 about ten miles south of Crescent City, which sits precariously above the Pacific Ocean. Built on an active landslide, the road has steadily slipped towards the Pacific Ocean, including a fairly substantial road failure in winter in 2017. In many areas, the road is no longer in its original alignment, having slipped further down the slope. The area that has experienced the greatest movement has moved 40’ horizontally and 30’ vertically so far. The question is not if the road will fail, but when and how badly.

Congressman Jared Huffman has convened a stakeholder group to help work through some of these issues. EPIC, Friends of Del Norte, and Save the Redwoods League sit on this group to provide input from the conservation community. The stakeholder group has met numerous times over the past three years to consider the project. The unanimous conclusion of the group, so far, is that something has to be done to improve the existing road. The question is what, where, and at what cost.

Caltrans is considering possible alternatives and reroutes. Of the six initial options presented by the agency, each has something that would ordinarily rule out that alternative from further study—from massive cost (Alternative F, a deep tunnel under the problem area, would cost one to two billion dollars, if it is even feasible at all!) to large impacts to old-growth (Alternative A2 would affect 3 acres of old-growth redwoods, including the loss of 30-50 trees) to technical feasibility (Alternatives C3-C5 are also in areas prone to sliding and may not be any better at staying open than the current route).

At the most recent stakeholder meeting, Caltrans has introduced two more alternatives: Alternative X, which would take drastic actions to stabilize the current alignment, and Alternative L, which would move the road slightly uphill, perhaps better positioning the road for the future). From their initial descriptions, EPIC is intrigued and excited to develop these alternatives further. Both alternatives initially appear to have the smallest environmental impacts—neither would affect old-growth nor require any stream crossings. Both are relatively cheap too, with a back-of-the-envelope estimate of $100-300 million, making them appear more feasible in our eyes. There are downsides too. Both would be costly to maintain and still prone to failures like the current road has experienced.

To further narrow their thinking, Caltrans has completed an “expert risk assessment,” where the agency has employed the help of geotechnical experts from across the West Coast to do an initial assessment of the various alternatives. The assessment focused on three factors: the cost to maintain the road (“cost”), likelihood of impairments to mobility, such as temporary lane closures for road work (“mobility”), and the risk of a full road closure (“closure”). One alternative, the long tunnel under the problem area (Alternative F) scored far better than the rest—but this alternative is the most expensive to build in the first place (“cost” in the report only concerns the cost to maintain) and the agency lacks the geotechnical data necessary to understand if this alternative is even possible. So it may be cumulatively cheaper to build a less expensive road but pay higher annual maintenance costs than to build an expensive road that doesn’t cost much to keep up.

The geotechnical analysis is only part of the consideration of values necessary to refine the alternatives. It doesn’t include consideration of environmental values, like preservation of old-growth or sediment inputs to rivers. To refine the alternatives further, Caltrans will conduct a “value engineering analysis” that will require soliciting thoughts from stakeholders about their deeply held values. These values will inform what alternatives that Caltrans will further decide.

By November 2018, Caltrans hopes to begin “scoping” under the National Environmental Policy Act (NEPA) and the California Environmental Quality Act (CEQA). NEPA and CEQA are the laws that require the agency to evaluate the potential environmental impacts of the various alternatives. The project will still take many years to complete, with Caltrans searching for money from federal and state coffers.

EPIC will keep our members informed as we learn more information.