By Nick Houtman
MANY SEASHORE DWELLERS face a tough question: How should they protect their property from rising seas and pounding waves? They can try to keep the surf at bay by building walls, or they can adjust to the slow but steady encroachment of the ocean.
Such choices are becoming particularly acute on the West Coast. For decades, winter storms have claimed roads and homes close to the water’s edge, especially those built on soft soils. As sea levels rise, accelerating erosion poses a challenge to existing as well as to new development.
In Tillamook County, homeowners and policymakers have been wrestling with this issue with assistance from faculty and students at Oregon State University. Through a program known as the Tillamook County Coastal Futures Project, they are exploring the long-term consequences of the rules that define how and where development can occur.
To prime their thinking, researchers and participants developed six scenarios — descriptions of policy options and the outcomes in the year 2100 — and showed the results with maps, charts and illustrations. Each scenario was analyzed through the lens of future population growth as well as ocean conditions that reflect potential changes in climate, El Niño and ocean waves.
“We had a diverse group of people,” says Peter Ruggiero, Oregon State coastal geomorphologist. “Some people favored policies that protected infrastructure, and some favored policies that affected recreation or habitat. The scenarios emphasized the tradeoffs between them.”
One scenario called “Status Quo” assumed that beaches, homes and businesses would be maintained using existing local, county and state policies. Another known as “Laissez Faire” allowed property owners to protect their homes and businesses regardless of state law and local zoning. A third, “Realign,” assumed that development would retreat landward as seas rise. A fourth, “Neskowin,” mirrored policies adopted by that southern Tillamook County community, approved by Tillamook County Commissioners and eventually upheld by the state Land Use Board of Appeals.
Through each scenario, participants could visualize changes in things they care about such as beach access, the number and locations of structures and the extent of shorelines armored with concrete or rock walls. The estimated costs associated with each scenario were also presented.
“Our main effort was to develop an approach where the stakeholders could see the impact of each decision-making context on property and coastal resources,” says Ruggiero.
One significant finding, he adds, was a surprise. Zoning decisions made now will have dramatic effects on what coastal communities look like in 2100. In fact, the differences exceed the range of uncertainties associated with climate change.
“We found for some scenarios that the influence of different policies had more impact on the variability of these things that people care about — such as the number of houses impacted — than even the massive uncertainty associated with sea- level rise,” says Ruggiero. “It tells people that even under a 1.5-meter (5 feet) sea-level rise by the end of the century, there are still decisions that we make now that can change the coastline.”
With support from the National Oceanic and Atmospheric Administration, the Tillamook project has entered a second phase to explore impacts on so-called ecosystem services, the benefits associated with beaches, sand dunes and other landscape features.