Online Tidal Datum Computations

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Convert your data to information. Upload water level measurements and get tidal datums referenced to the National Tidal Datum Epoch within minutes.

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JOA Surveys has completely automated the tidal datum computation process. Water level enthusiasts no longer need to immerse themselves in tidal datum computation methodology. Instead this tool allows a user to focus their effort on data interpretation.

The only required inputs are a comma delimited file and the users email address. The input water level data can be sampled at any interval from 1 second to 60 minutes. The data must span at least 24 hours. The resulting tidal datums are referenced to the current National Tidal Datum Epoch, when applicable.

All of the computations are based on the methodology developed by the United States' water level and tidal datum authority NOAA's Center for Oceanographic Operational Products and Services. The tool does not derive prediction based datums such as Lowest Astronomical Tide.

The results are dependent on the quality of the data being submitted, duration, and the applicability of the controlling station selected (if chosen).

Registered Users: 106
Computations Served: 591



JOA Surveys, LLC does not guarantee availability, reliability, and performance of the Online Tidal Datum Computation Tool and accepts no legal liability arising from, or connected to, the use of information on this website or use of this service. JOA reserves the right to view any information contained in the uploaded file.