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

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2. LOCAL FEATURES
Local Bathymetry
The local distribution of water depth was surveyed in May,
June and July 1966 from north of the mouth of the St. Joseph
River to south of the plant site. The region is characterized
by gentle and regular bottom topography (Fig. 5). The 100-foot
depth isopleth lies at about six miles from shore. Isobaths
less than 40 feet are regular and parallel to the shoreline.
Isobaths between 40 and 75 feet exhibit some irregularities
between St. Joseph and Grand Marais Lakes, becoming regular and
essentially parallel to shore south of Grand Marais Lakes.
In the whole extent of the survey there were two sand bars
close to shore. They have been subject to spot tests between the
plant site and St. Joseph, but not in detail sufficient to warrant
their charting. Along the front of the plant property and to one
mile south of Livingston Road these bars have been surveyed in
sufficient detail to chart. They are shown in front of the
plant property and to the south boundary of the survey in Figure
5. The inner bar averages about 500 feet from water's edge over
the area of detailed survey, but lies slightly nearer to shore
off the north edge of the plant property. At the north edge of
the site a taut-wire measurement on 13 September showed the inner
bar to be about 450 feet from water's edge. The 500-foot distance
from the beach edge at the point fell into 11 feet of water outside the crest of the inner bar.
The outer bar lies about 1000 feet from water's edge at the
north edge of the plant site. It is situated about 1100 feet off