Radar Inlet Observing System

SAVES $5 THOUSAND AND 10 DAYS PER SITE COMPARED TO TRADITIONAL SURVEYING METHODS

Corps researchers developed the Radar Inlet Observing System (RIOS) to provide stakeholders interested in processes at tidal inlets and harbor entrances a continuous near real-time measure of wave conditions and channel depths and positions. Sediment transport in shallow, coastal environments is often difficult to measure, particularly during storm events when shoal and channel positions shift substantially and wave conditions are too treacherous for small survey vessels to safely operate. RIOS utilizes X-band radar to remotely measure wave parameters and exploits wave behavior to determine shoal and channel positions. Use of an X-band radar signal provides coverage over a large area (up to 5 km) from a single, low-elevation position and offers continuous operation throughout the night and during low-visibility storm conditions.

PROBLEM: The Corps is charged with maintaining safe, navigable tidal inlets while minimizing adverse effects to adjacent property and the environment. Balancing navigable channels with healthy beaches and ecosystems can be a challenge, particularly on a continual, up-to-date basis when the positions of channels and shoals are dynamic and the volume of infilling sediment is costly to quantify on a regular basis.

SOLUTION: Corps researchers designed RIOS to analyze metrics for engineering support along shorelines, harbor entrances and tidal inlets over extended, hourly time periods. RIOS can infer bedform migration, channel infilling, wave angle and bathymetry effectively at remote locations. These lowcost, near real-time measurements of waves, channel positions and depths improve safety at navigable coastal inlets.

IMPACT: Corps dredging and placement strategies are optimized by rapid, cost-effective measures that address shoal migration and encroachment into navigation channels. RIOS data can facilitate understanding of inlet dynamics to focus and potentially defer dredging efforts. RIOS observations also guide sediment placement design by monitoring the rate and direction of sediment movement after placement.