LITTORAL PROCESSES IN LAKES

Abstract

The purpose of this paper is to present the general topic of lake processes to an engineering audience from a geological point of view. It is apparent that the shores of larger lakes present many problems in common with the sea coast, but the absence of tides, and of first-rank storms, means that geological processes are less marked, and structures may in general be smaller. In contrast to many coastal areas, the Great Lakes probably have less consolidated materials in their banks and bluffs, inasmuch as the basins lie mainly in glacial deposits. Hence rates of erosion may be much greater than on harder coastal rocks. The effect of long-period changes in level also introduce problems of selecting distances above and below lake datum in structures, to allow for the more shoreward wave action during times of high levels. The much leaner shore drift along lakes as compared to the oceans also means that problems of beach development and maintenance may be more difficult to solve. Greater reliance on imported sand in closed systems seems to be the trend in some larger communities where the demand for recreational beaches is great.