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

29

The available figures about water levels of the 26 June 1954
seiche are:
Level, variation of 3.2 feet at Wilson Ave. Crib (Chicago)
10 feet rise of water level at North Ave. (Chicago)
8 " I" " ", i " Montrose Harbor (Chicago)
2.4 " " " " " " Chicago River mouth
2 " " " " " " Waukegan, I11.
6 " " " " " " Michigan City, Ind.
It appears that all these figures, except that for Michigan
City, are from the wave reflected from the eastern shore; the
Wilson Ave. Crib figure probably can be taken as indicative of
the height of the deep-water wave involved in the Michigan City
and Chicago regions as can that for Waukegan for that area; higher
figures represent trapping of the wave by harbor structures or
local shoreline configurations.
Data for other seiches large enough to have been noticed
and recorded are:
19 August 1921, Milwaukee, Wisc.
Water rose 1.5 feet and fell 1.0 feet all within a half hour.
A few hours later the water fell 2.0 feet in 10 minutes.
21 June 1954, Chicago, Ill.
Water level variation of 1.3 feet at Wilson Ave. Crib.
6 July 1954, Chicago and Waukegan, Ill.
Level variation of 4.2 feet at Wilson Ave. Crib.
" " " 4.1 " Waukegan.
3 August 1960, Chicago and Wilmette, Ill.
Water rose 2.5 feet at Wilmette.
" " 4.0 " " Montrose Harbor.
" 3.0 " " Belmont Harbor.
On the southeastern shore the seiche arrives with the squallline passage. The seiche does not have the rapidity or damaging
power of a wind-wave of equal height. Instead, the rise of water
is continuous over several minutes, and damage is primarily due
to flooding. Loss of life appears to be confined to non-swimmers