PDF Version
Device measures tidal seepage over time and can obtain multiple samples per use
The U.S. Navy seeks to commercialize U.S. Patents 6,993,437 (Tidal seepage meter), 7,424,375 (Tidal seepage meter), and 7,672,795 (Method for sampling seepage).
Background
Tidal seepage is the exchange of water between ground water and adjacent waterways (lakes, rivers, or oceans). During the ebb and flow of the tidal cycle, water moves through marine and aquatic sediment, flowing between groundwater and surface water. Tidal seepage can carry pollution and contaminants from groundwater into lakes, rivers, or ocean waters. Tidal seepage meters measure this flow and are positioned beneath the water body and partially embedded in the underlying sediment. The devices quantify the variable rates of flow and chemical transport between groundwater and surface water. Typical seepage meters measure aggregate seepage over time and do not provide data on how seepage changes during the tidal cycle. Additionally, typical meters can only obtain one sample per use, which increases cost and danger to divers by requiring them to make repeated dives to collect multiple samples.
The Technology
SSC Pacific has developed a method and apparatus for measuring changes in tidal seepage during the 24-hour tidal cycle, as well as for obtaining up to six seepage samples per use. The meter consists of multiple sampling chambers linked to a controller programmed with a sampling time schedule. The meter could be programmed to obtain six samples at four hour intervals, which 
represents a one-day tidal cycle. The controller activates a motor, which rotates sample containers in line with a seepage inlet port, capturing sample water. After the sample is taken, a stopper valve prevents water from flowing out of the sample chamber. At the end of the sample cycle, the containers are retrieved and the seepage water is analyzed.
Key Benefits
Development Status
- For more information on technology transfer, please contact us at (619) 553–5118 or email ssc_pac_t2@navy.mil
- SD 866, October 2009. SSC Pacific, San Diego, CA 92152–5001. Approved for public release; distribution is unlimited.