The extensive intertidal flats visible at very low tide from the Causeway are a unique Bowen Island shoreline.
The stream mouth of Terminal Creek, Bowen’s largest stream, flows across these tidal flats at a low tide. Terminal Creek drains one-third of the land on Bowen Island and carries not only its waters to the sea but also mud and sand. The mud is carried out to sea and settles in deep water, while the heavier sand is deposited near the shore. As a result, an extensive sheet of sand fills the river mouth area, creating a unique habitat for clams and other burrowing invertebrates.
An aerial view of the sand flats taken at a very low tide in 2011. The Terminal Creek water pond behind the Causeway spills into a channel that is carved across the sand flats. The sand has been eroded by Terminal Creek from its watershed over thousands of years and carried to the sea where it has been deposited. The sand flats slope gently underwater out into Deep Bay, visible in this photo, where they have built a thick accumulation of sand. Geologists call the combined sand flats and the submarine sand pile a stream delta.