Crescent Harbor, located in Crescent City on California’s far north coast, is a small, sheltered inlet connected to the Pacific Ocean. While primarily known as a working harbor that supports commercial and recreational fishing, boating, and tourism, it also functions as a tidal estuary influenced by ocean tides and freshwater inputs from nearby streams. These interactions create dynamic water level patterns and drive changes in salinity and circulation within the harbor.

Crescent Harbor lies within a region shaped by powerful coastal processes, including strong tides, winter storms, and tectonic uplift. The surrounding landscape and offshore bathymetry also make it vulnerable to tsunami impacts, which have historically affected the harbor’s infrastructure. Daily and seasonal changes in water level are important to understand for both ecological and safety reasons.

Water level monitoring in Crescent Harbor helps track tidal cycles, storm surge, and long-term sea level trends. These data are essential for harbor operations, coastal planning, and efforts to improve resilience against flooding and future climate impacts.