21 
current measurements show that the direction and velocity of flow 
is highly variable. Current velocities range from 0.1 to 0.4 knot, 
with about 80% of measurements from all methods being about 0.2 knot. 
Under some conditions surface velocities may reach a maximum of 0,8 
knot. These show a predominant direction between east and south at 
points near the center of the bay. 
On share in the southern part of Santa Monica Bay are two 
steam plants, which discharge sea water having a temperature of 
approximately 80° F, The sewage from the Hyperion Treatment Plant 
in El Segundo also enters the sea at a temperature of approxi- 
mately oe F, The sewage, coupled with the high temperature water 
from the steam plants, forms a wedge of warm low density water in 
this nearshore area. It is probably that the density surface 
generated by this artificially warmed water is sufficient to pro- 
duce a current flowing in a northerly direction at velocities up 
to, and in some instances exceeding, 0.4 knot. The velocity and 
direction of flow changes in the vicinity of Playa del Rey, where 
afternoon westerly winds may force the flow shoreward between 
Playa del Rey and Venice. Under no-wind conditions a flow with 
a much decreased velocity may continue past Santa Monica terminating 
in the waters off Malibu. 
The general surface water motion is controlled by the dominant 
southwest and westerly winds. The wind driven water is directed 
shoreward in the central part of the bay and then upon reaching 
the nearshore zone diverges to the north and to the south. The 
northerly component when associated with the man-made current 
frequently causes the sewage to flow through offshore waters as 
far north as Malibu Point. The southerly component is much less 
