Tides, Currents, & Swells of the Comau Fjord

The tides in the Comau estuary are highly variable. The daily amplitude can change from a maximum of 7 meters to a minimum of 2 meters in one month (see tides 1st week of 02-2006), depending on the moon phase. This permits locals to easily beach and float their boats among other things.  Furthermore waters cover and uncover large portions of the coastline, creating a unique assemblage of organisms adapted to extreme environmental changes.

Currents due to swell have little effect, usually varying in velocity from one to two knots. During the winter months, the outgoing current may slightly increase in intensity as a result of the rise in freshwater input from the rivers and streams that flow into the eastern arm of the estuary.

Swells from the open ocean are close to non-existent due to interference from the neighboring island of Chiloe as well as orientation of the Comau Fjord. The water is usually tranquil, only interrupted by the presence of wind-forced waves of small height and length. These are produced mainly by orographic winds that are channeled through the steep and rocky walls of the fjord. Swells produced by this wind are highest at the mouth of the Comau Channel, near the mouths of the Calhuelmo and Quintupeu fjords, reaching 5-6 meters in length and 60-80 cm in height. On occasion, these orographic winds can hit the zone with unexpected fury and produce risk for smaller vessels.