Winter storms in the Eastern Pacific routinely generate huge ocean waves that hit the Oregon Coast, making bluff and dune erosion a common occurrence. Extreme erosion events can occur when large wave events are combined with higher than normal tides, storm surge, or higher water levels associated with El Nino. 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.
Shoreline protective structures have been and continue to be built by property owners in Oregon to armor eroding bluffs and dune-backed shoreline. There are many different types of shoreline protective structures. The most common form in Oregon is the riprap revetment, which consists of large boulders placed on the bluff or dune slope over smaller rock fill and/or filter fabric. Other less common types of shoreline protective structures includes seawalls constructed of formed concrete, concrete blocks, or in a few cases treated wood.
Shoreline protective structures are very expensive to install, and can have several effects on a public beach such as beach narrowing, scenic degradation, and requirement for continued maintenance with heavy equipment. In addition, placement of a hardened structure in front of one property may cause adjacent properties to experience increased erosion.
Protecting the Beach
The 1967 Beach Bill declared the state’s beaches to be a state recreation area from the extreme low tide line to the line of vegetation, and gave Oregon Parks and Recreation Department responsibility for review of permits for alterations to the ocean shore, in accordance with standards designed to promote the public health, safety and welfare.
In addition, statewide landuse planning Goal 18 specifically relates to management of beaches and the adjacent shoreline, with specific provisions for the use of shoreline protective structures:
Permits for beachfront protective structures shall be issued only where development existed on January 1, 1977. Local comprehensive plans shall identify areas where development existed on January 1, 1977. For the purposes of this requirement [..] "development" means houses, commercial and industrial buildings, and vacant subdivision lots which are physically improved through construction of streets and provision of utilities to the lot and includes areas where an exception to (2) above has been approved. The criteria for review of all shore and beachfront protective structures shall provide that:
This means that permits for shoreline protective structures may be considered only where development existed on January 1, 1977.
To help make it easier to find out where these Goal 18 "developed" areas are, the Oregon Coastal Management Program is conducting a project to inventory the 1977 development status of all oceanfront properties. The results of this study are being made available county by county as the analysis is completed.