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

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velocity from sets inside the outer bar in Table 1), we have
averaged the two velocities to obtain 0.35 ft/sec as the mean
speed of effluent movement. Over 15 hours of unidirectional
wind at this mean speed the plume should reach to a distance of
5.25 miles.
Since both these estimates are preliminary, we take the mean
(6.4 miles) as a second approximation of the distance to which
the plume of plant effluent might reach before vanishing under
light-wind alongshore-current conditions. Refined current
velocity data from our 1967 work may permit recomputation of
these estimates. If so, they will be amended.
Though the second approximation is preliminary, it is unlikely that plant effluent would reach the intakes at St. Joseph
(9 miles), New Buffalo (16 miles), Grand Beach (18 miles), or
Michiana (19 miles). Because of the protection afforded by the
outflow of the St. Joseph River, described previously, it appears
unlikely that plant effluent would reach the Benton Harbor intake
at 11 miles distance.
It appears probable that cooled and diluted plant effluent
could reach the intakes at Bridgman (2-1/2 miles) and Orchard
Beach (ca 7 miles) under the occasional northwest winds of summer,
but summer northwest winds are cool and usually not light in
velocity. The infiltration collectors at Bridgman and Orchard
Beach would appear to have certain inherent protective characteristics already mentioned.
Under the conditions we have so far observed at river mouths,
the river water reaches to the lake bottom for a short distance