Estuaries are where rivers meet the sea — forming transition zones where fresh and saltwater mix. This creates rich, productive ecosystems for humans and animals alike, often forming the heart of coastal communities. Estuaries are some of the most diverse habitats on the planet. They support wildlife such as birds and fish, especially salmon, and serve as vital nurseries for most commercially harvested fish and shellfish. Estuaries are crucial for coastal protection, acting as buffers against storms and floods, while also filtering water and storing carbon. They also support significant economic activities like tourism, fishing, and recreation.
In Oregon land use, an estuary is defined as a body of water semi-enclosed by land, connected with the open ocean, and within which salt water is usually diluted by freshwater derived from the land. Estuaries include estuarine water, tidelands, tidal marshes, and submerged lands. Estuaries extend upstream to the head of tidewater, except for the Columbia River Estuary, which by definition extends to the western edge of Puget Island.
In Oregon, coastal counties and cities are required to develop and implement plans in coordination with state and federal agencies to manage activities and uses in estuarine waters and adjacent lands. Statewide Planning Goal 16: Estuarine Resources provides guidance for the planning and management of Oregon's estuaries.
Statewide Planning Goal 16: Estuarine Resources
The aim of Oregon Statewide Planning Goal 16 is to protect the long-term values, diversity, and benefits of estuaries and associated tidal wetlands. At the same time, the goal directs local governments to provide for appropriate restoration and development of these resources. The goal relies on a classification system that specifies the level of development allowed in each estuary. All local governments with authority over an estuary must prepare and adopt an estuary management plan and land use regulations according to four classifications:
-
Deep-draft development — estuaries with maintained jetties and channels more than 22 feet deep;
-
Shallow-draft development — estuaries with maintained jetties and channels up to 22 feet deep;
-
Conservation — estuaries without a maintained jetty or channel within or adjacent to an urban area with altered shorelines;
-
Natural — estuaries without a maintained jetty or channel not adjacent to an urban area and with little development.
Of Oregon's 22 major estuaries, three are classified as deep-draft development estuaries, eight shallow-draft development, six conservation, and five are natural estuaries. Seventeen other estuaries are considered minor estuaries and are classified as natural or conservation. Minor estuaries are formed where smaller rivers and creeks meet the ocean.
Estuary management plans are multi-jurisdictional. Counties are the lead jurisdiction for the plans for every estuary within the county, while cities adopt certain parts of the plan that are within their jurisdiction, creating a unique joint management relationship. Federal agencies such as the Army Corps) and state agencies such as the Department of State Lands often have additional regulatory authorities within estuary landscapes, creating additional multi-jurisdictional complexities. It is important to update these plans through the
post-acknowledgement plan amendment process to foster continued coordination between counties, cities, and state agencies and improve management over time as community and state needs and requirements change.
Oregon Administrative Rule 660-017 outlines state regulations relating to Goal 16 and estuary classification.
Estuarine Resilience Action Plans
The Coastal Division at DLCD has been leading county-focused processes that have resulted in Estuarine Resilience Action Plans (ERAPs). These plans are the result of a partner-led framework for strengthening the natural hazards resilience of estuaries, communities, ecosystems, and infrastructure in several coastal counties. Developed through an extensive collaborative process involving local governments, tribal partners, conservation organizations, watershed councils, state and federal agencies, and other local community partners and interested parties, the ERAP provides actionable strategies to reduce natural hazard risks, restore degraded systems, and support long-term adaptation in a changing climate and landscape. So far, plans have been completed for Coos, Tillamook, Lane, and Lincoln Counties.
Estuarine Management Units
In addition to its overall management classification, each estuary contains individual management units or zones. The boundaries of the management units are determined by the types of resources in the area and the extent of past alterations. There are three types of estuarine management units: natural, conservation, and development. Each type is "a discrete geographic area, defined by biophysical characteristics and features, within which particular uses and activities are promoted, encouraged, protected, or enhanced, and others are discouraged, restricted, or prohibited."
While certain types of land use are allowed or prohibited for all estuary management units, other types of land use may be allowed if they pass the Goal 16 resource capability test. The resource capability test determines the impact of a proposed use and whether the resources and ecosystem will be able to adapt and continue to function.
An estuary’s classification determines what type of management units can be used within it.
-
Natural estuaries include only natural management units
-
Conservation estuaries can include natural and conservation management units
-
Shallow and deep draft development estuaries can include natural, conservation, and development management units.
Natural Management Unit
Natural units are managed to protect natural resources, such as areas with significant fish and wildlife habitat, especially those that are the least altered or developed. They contain extensive salt marshes, tide flats, eelgrass meadows, algae beds, and a variety of fish and wildlife.
Permissible uses include:
- Low-intensity water-dependent recreation,
- Research,
- Passive restoration,
- Bridge crossings, and
- Limited use of riprap.
Uses that may be allowed under the resource capability test include:
- Boat ramps,
- Aquaculture,
- Active habitat restoration,
- Pipelines or other utility crossings, and
- Bridge crossing support structures.
Conservation Management Unit
The conservation unit is applied to areas that have been altered from their natural state. While their natural resources and habitats may be smaller or less significant than those in natural management unit areas, resource protection is still important for their long-term quality and health. A variety of development is allowed as long as there are no major alterations.
Uses that may be allowed under the resource capability test include:
- High-intensity water-dependent recreation,
- Marinas,
- Certain water surface uses that do not require dredging or filling,
- Habitat restoration, and
- Aquaculture.
Development Management Unit
Development units are reserved for areas with fewer natural resources that have been the most altered. These are typically applied to deep-water areas close to shore, navigation channels, and subtidal areas suitable for disposal of dredged materials. In addition to uses allowed in natural and conservation management units, permissible uses include:
- Dredging and filling,
- Water-dependent commercial activities, and
- Dredged navigation channel and water storage areas that support industry, commerce, and recreation.
Non-water dependent or related uses and mining may be permissible if they are consistent with the purpose of the relevant development management unit and adjacent shorelands.
In addition to the activities and uses outlined in each management unit types, Goal 16 also includes several implementation requirements that must be addressed. These requirements include an impact assessment for:
- Alterations to the estuary,
- Dredge and fill tests,
- Water quality evaluation,
- Freshwater flows,
- Mitigation and restoration sites,
- Dredged material disposal, and
- Docks.
Most Goal 16 requirements are implemented through locally adopted estuary plans, but some are applied by state agencies through their review of various permit applications.
Additional Resouces