Standard Port

A primary tidal reference location for which full tidal predictions, including times and heights of high and low water, are published. 

Standard Ports serve as the main reference points for tidal predictions in nautical almanacs and tide tables. These ports have well-established tidal data based on long-term observations, allowing mariners to plan voyages, anchoring, and harbour entries with accuracy. Tidal information for Standard Ports includes times and heights of high and low water, which can be used directly or as a reference for calculating tidal conditions at Secondary Ports. Secondary Ports rely on tidal differences, or corrections, relative to a nearby Standard Port to estimate their own tidal conditions. The selection of Standard Ports is based on their strategic importance, reliable tidal records, and geographical distribution. They are commonly located at major harbours, estuaries, or coastal locations with significant maritime traffic. By using a Standard Port’s tidal predictions, navigators can determine safe passage times, avoid grounding, and optimise fuel efficiency.