Modernizing Aging Tide Gates for the Health of Oregon Estuaries & Farmlands

The Oregon Tide Gate Partnership is a coordinated effort of state and federal agencies, agriculture and conservation organizations, county leaders, and coastal landowners. Together, we are working to achieve more resilient coastal communities by protecting landscapes that support local economies and enhancing the ecological function of Oregon’s estuaries for fish and wildlife.

The tide gate infrastructure in Oregon is aging. Much of it will benefit from repair, replacement, or removal in the coming years. The Tide Gate Partnership is focused on addressing the challenge of repairing this aging tide gate infrastructure and providing assistance to tide gate owners in coastal Oregon.

Did you know?

  • There are about 1,000 tide gates in estuaries along the Oregon Coast and along the lower Columbia River, many in need of repair.
  • If tide gates fail, roads, businesses, homes, and agricultural lands become more vulnerable to flooding and intense winter storms.
  • A well-designed and managed tide gate keeps farmlands productive, manages tidal flows to allow migration of native fish, and maintains water quality.

Traditional tide gate design
photo: Beaver Slough Drainage District

What is a Tide Gate?

In Oregon, tide gates are commonly used to control water in tidally influenced areas along the coast and lower portions of the Columbia River Basin. Traditionally, tide gates are constructed by integrating one-way doors (i.e. the tide gate) into a dike. Freshwater drains from streams above the tide gate during outgoing tides. Water pressure from incoming tides closes the gate, protecting agriculture, infrastructure, and other developed landscapes from tidal inundations. Unfortunately, preventing inundation can also slow or prevent tidal flows into the estuaries, which can impede the migration of native fish, diminish water quality, and reduce estuarine ecological functions.