This data layer shows the locations of NOAA tide gauges in Maryland. Knowledge of the timing and strength of tidal currents is extremely important for safe navigation in coastal waters. Tidal currents are almost always the strongest current experienced by vessels operating offshore and for considerable distances inside bays and river estuaries. Standardized procedures exist for analyzing tidal current data to separate the tidal and nontidal parameters. The tidal parameters are used to produce the National Ocean Service Tidal Current Tables. There are currently 41 tidal current reference stations where daily predictions are made based on information obtained in short-term current studies. Additional predictions are made for 2200 locations referenced to these tidal current reference stations. Predictions have varying degrees of accuracy dependant on the age of the data, the length of the measurements and the degree of non tidal influence a given location experiences. A clear understanding of current patterns in ports and estuaries which have economical and commercial importance is vital to ensure safe navigation and help in preventing accidents. In ports where currents are dominated by non-tidal factors, real-time current measurements are preferred. Data was downloaded from the NOAA website at http://tidesandcurrents.noaa.gov/cdata/StationList?type=Current+Data&filter=active.