Oregon Coastal Atlas

Oregon's 22 "major" estuaries play a vital role in the ecological and economic health of the coast and the entire state. For example, they are ecologically important to many fish and wildlife species, providing migration routes and habitat for reproduction, rearing, resting, and foraging. Healthy estuaries provide important habitats for many species we value such as salmon, herring, flounder, crabs, oysters, clams, wading birds, ducks, geese, shorebirds, and harbor seals. 

Headlands divide the Oregon coast into sandy shore compartments, or littoral cells. Within each littoral cell, features such as inlets, jetties, and rocky outcrops define the boundaries of even smaller compartments, or subcells. As many as 21 littoral cells have been identified along the Oregon coast ranging from less than 10 km to over 100 km in length. The sandy dune backed shoreline within these cells comprise about 262 of Oregon's 362 mile coastline, the remainder being headlands, bluff-backed or inlets.

More than 1400 rocks and islands are sprinkled along nearshore zone of the Oregon coast, usually in association with cliffs and other resistant rocky features of the shoreline. These rocky remnants are dramatic and picturesque, but the are also valuable habitat that supports a diverse coastal ocean ecosystem. Most of these rocks and islands are in the Oregon Islands National Wildlife Refuge and are home to major colonies of seabirds, such as the common murre and marine mammals, including the threatened Steller sea lion. 

Oregon ocean areas stretch approximately 360 miles from the mouth of the Columbia River to the California border and extend some 14 to 40 miles into the ocean.

The state's ocean jurisdiction [the Territorial Sea] extends three nautical miles from shore [Mean Low Water], although offshore rocks and islands can extend this area seaward, such as at Orford Reef near Cape Blanco.

There are two major pieces of public policy that provide and protect the publics' public access rights; the famous Oregon Beach Bill of 1967 and the State Planning Goal 17 for Shorelands. First, the Beach Bill established a permanent public easement for access and recreation along the ocean shore seaward of the existing line of vegetation, regardless of ownership. 

The Oregon Beach Monitoring Program (OBMP) monitors selected Oregon coastal recreation waters for the presence of fecal bacteria, and reports elevated levels to the public. The OBMP is funded by a grant from the Environmental Protection Agency, is administered by the Department of Human Services and collaborates with Oregon Department of Environmental Quality, and the Oregon Parks and Recreation Department.

The waters off the Oregon coast are part of the California Current System, one of the most productive marine habitats in the world. The rugged coast encompasses large expanses of rocky shorelines, islands, and offshore sea stacks that provide nesting habitat for approximately 1.3 million nesting seabirds representing 15 species, distributed over a total of 393 colonies. The largest colony in the state occurs at Three Arch Rocks NWR, where over 225,000 seabirds of 10 species nest.

Coastal erosion is a natural process that continually affects the Oregon coast. Erosion becomes a hazard when human development or public safety is threatened. Beaches, sand spits, dunes, and bluffs are constantly affected by waves, currents, tides, and storms, resulting in chronic erosion, landslides, and flooding. Changes may be gradual over a season or many years. Changes may also be drastic, occurring during the course of a single storm event.

Oregon’s ocean shore is subject to a wide range of geologic forces and climatic conditions that continually shape the coast and put life and property at risk. As development progresses into steeper slopes, ocean bluffs, and dune areas, the level of risk increases, as does the need to make better decisions about where to build and what to do to protect existing development.

Winter storms in the Eastern Pacific routinely generate huge ocean waves that hit the Oregon Coast, making bluff and dune erosion a common occurrence. Erosion can threaten buildings and roads resulting in a desire to "harden" the shoreline against wave attack. At the same time, Oregonians have always considered the ocean beach to be a public resource and legacy, and shoreline armoring, while sometimes able to protect private property, can have negative effects on the public beach.

Landslides are a serious geologic hazard, threatening public safety, natural resources, and infrastructure, and millions of dollars are spent annually to repair landslide damages in Oregon. Although landslides occur virtually every year in parts of Oregon, general awareness and recognition of the hazards remain relatively low. The ephemeral nature of landslides, the location of many events in relatively undeveloped areas, and the fact that landslide damages are often quickly repaired contribute to the low awareness.

Tsunamis rank as one of the most dangerous natural disasters that could affect the Oregon coast. Although not frequent in occurrence, the damage caused by these catastrophic events is immediate and life threatening. The most destructive type of tsunami would be generated locally by a Cascadia subduction zone earthquake of magnitude of 8.0 to 9.0, or greater. Devastating tsunamis waves would be expected to arrive along the Pacific Northwest coast including Oregon within 5 to 30 minutes after such an event, providing very little evacuation time.