This page describes an animation of a numerical simulation of the surface current flow on Casco Bay using an early version of FVCOM (The Finite Volume Community Ocean Model) developed by some smart people out of UMass-Dartmouth. The currents are calculated based on tides, wind, temperature, and salinity, as well as the bathymetry. —Ed note: This study used a computer model to examine how water moves through Casco Bay during the spring. The model included the shape and depth of the bay, tides, wind, and freshwater flowing from the Kennebec and Androscoggin rivers. Because the model was detailed enough to include the coastline and islands, it could show small-scale currents and eddies as well as the larger circulation patterns.

Timeframe of simulation: 2000 May 9, 2005 to 2000 May 10, 2005 (I think I have this time correct—it converts to 0000 May 10—2400 May 10 in UTC time frame, which makes some sense). Here are the predicted and verified tides reported from the Portland tidal gauge on May 9-10, 2005. Tap the tidal chart to see closer details:

The simulation of surface currents below in Casco Bay below shows Fleet 27's racing area. Use the video controls in the animation to scrub through the tidal changes and compare the flow with the corresponding stage of the tide. Anyone see any patterns? The current flow does not seem to sync with the times of high/low tide, except maybe at the start and end. But, surface currents are complicated, and may be driven by freshwater from inland and the weather, as much as by the tidal changes. And the tide is complicated on Casco Bay. The FVCOM simulation is available (for free) if there is anyone interested in pursuing this further.