US Patent 7637168 Seepage meter for measuring submarine groundwater discharge

Automated seepage meters that can detect and quantify groundwater outflow and seawater infiltration. In addition to its capabilities in saltwater-influenced systems, the automated seepage meter can detect and quantify groundwater outflow and surface water infiltration in freshwater systems (e.g., aquatic, riverine, lacustrine environments). Based on a dye-dilution technique, this instrument provides high resolution time series data for submarine groundwater discharge to the coastal zone. The dye dilution method may employ two repeatable steps: the timed injection of a water-soluble dye into a dye mixing chamber mounted in series with a seepage or collection chamber and the subsequent timed measurements of the absorbance of the dyed solution.