Currents and related problems at Metropolitan Beach, Lake St. Clair / John C. Ayers.

METHODS

Currents being basic to the problems, much work was done on
the determination of current patterns under various wind conditions.
In the study of alongshore currents at the Beach, it was
necessary to obtain a large series of observations. To this end
a combination wind-and-current recording station was installed
at the west end of the bathing-beach area. This station recorded
eight wind directions, two scales of wind velocity, and eight
directions of alongshore water current. These data established
the current directions that accompany each wind direction. They
also gave information on the relation of each month's winds to
the long-time mean winds.
Current-cross (drogue) studies of currents in the immediate
area of the Beach were carried out to verify the wind and current
data being recorded at the automatic station.
The wind instruments of the recording station were a standard
heavy-duty anemometer and wind vane coupled to an Esterline-Angus
operations recorder. The current indicator consisted of an inverted pendulum attached to a heavy base lying on the lake bottom
about 300 feet from shore. The pendulum stood erect in the water
as a result of styrofoam flotation in its upper end. In the base
of the pendulum four mercury switches oriented to the four main
directions were so mounted that current-induced tilt of the pendulum would cause contacts to be made and current direction to be
indicated on the operations recorder. Under westward current for
example, only the "west" switch would make contact; under south

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