General studies : November, 1967 / by John C. Ayers, Joseph C. K. Huang.

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spoiled later attempts by causing the fluorometer intake to
capture air bubbles. The very rapid dilution being undergone
by this dye patch illustrates the greater mixing effect of
higher winds.
Sufficiently calm weather did not coincide with availability
of the boat until late in October. At this time successful
dilution experiments were run on 25 and 26 October. A run
attempted under 20 mph winds from the southwest on 27 October
failed because the dye was moved across the inner bar into water
too shallow for the boat to reach it.
The alongshore current directions shown by the dye patches
are reported in the section on local currents.
On the basis of the data available, there appears to be a
reasonable dilution rate inherent in the natural regimen of alongshore currents. The natural regimen will, however, be modified
to a degree by the current created by the flow of plant effluent.
3. LOCAL TEMPERATURE CYCLES
The Annual Cycles of Water Temperature
From our own data collected in connection with other types
of investigations, we have assembled the surface water temperature
curves shown in Figure 8.
Though our ships cannot operate in winter to measure temperatures, each winter produces ice in the rivers, in the alongshore
waters, and floating ice-fields in the open lake. The presence
of ice indicates that 32~ F can be taken as a basic surface-water
temperature at the beginning and end of the year. Use has been