US Army Corps of Engineers
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CIRP - Coastal Inlets Research Program

Published Aug. 8, 2013
Updated: Feb. 13, 2020

The United States, through the U.S. Army Corps of Engineers (USACE), has national interest in the stability and evolution of coastal inlets. Almost $1 billion is expended annually to operate and maintain federal coastal inlet navigation projects, including the inlet channel, associated jetties and breakwaters, and adjacent inland waterways. The physical processes of coastal inlets span the navigation, shore protection, and coastal environmental missions of the USACE. 

  • Vital commercial and military navigation links.
  • Closely connected to beach stability and estuary health, locally and regionally.
  • Central for exchange of water, sediment, and nutrients between estuaries and seas.
  • Recreational opportunities for the nation and assets for the economic strength of coastal communities.

CIRP - The Coastal Inlets Research Program

Because of the multiple interacting forces and the numerous scales of geomorphic change ranging in time from days of a storm to centuries for long-term adjustment, the physical processes of inlets are poorly understood. Little quantitative information is available to predict infilling of navigation channels; long-term change in the nearshore, which affects channel and jetty stability; short- and long-term migration trends and cycles of inlets; and the interactions among inlets, adjacent beaches, and estuary.

The Coastal Inlets Research Program (CIRP) advances the state of knowledge and develops engineering technology for predicting the waves, current, sediment transport, and morphology change at and around inlets. Products of the CIRP improve management and design of coastal inlets through increased reliability of actions and reduction in operation and maintenance costs. The CIRP takes a variety of approaches, including developing concepts and theory for all relevant time scales, numerical simulation, field data collection, and laboratory experimentation. Reports and peer-reviewed articles provide the information gained from the CIRP to the USACE, scientific community, and public. 

Inlets Group
202 761-1850
Coastal Processes Branch, Coastal and Hydraulics Laboratory

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