Weeks Bay Reserve, Alabama

Tidal Range

Tidal range in the estuary is from 0.3 - 0.5 meters (1.0 - 1.5 feet).

River Flow

Weeks Bay has two major freshwater inflows, the Fish River from the north and the Magnolia River from the east. Mean combined discharge is estimated at nine cubic meters/second, with freshets up to four times larger. The Fish River accounts for approximately three-quarters of this freshwater inflow. During extreme flooding the Fish River has been estimated at 243 cubic meters/second. While the Fish and Magnolia Rivers have depth ranges from two-14 meters (six-42 feet), Weeks Bay averages less than five feet deep, with its western half three feet or less. The drainage basin of the Fish River can respond rapidly to local rainfall. Estimates of the replacement for water within Weeks Bay from freshets are two or three days to refill the Bay. Normal tidal exchange can do the same at three days. The salinity of Weeks Bay is strongly coupled to the salinity of the Mobile Bay estuary, which is controlled by the extensive seasonal runoff of the Mobile River system, and only secondarily a function of freshwater input from the Weeks Bay watershed.