in bar position, rates of shore retreat, and lake level change. A final 

 CERC report (Hands, in preparation, 1979) will integrate bar migration, 

 shore retreat, and lake level changes over the full period from 1967 to 

 1976; another final report will discuss the changes in shore retreat over 

 the whole eastern shore between 1970 and 1974 (Birkemeier, in prepara- 

 tion, 1979) . 



Earlier CERC reports (Berg, 1965; Berg and Duane, 1968) cover long- 

 term shore erosion and lake level changes and concern the behavior of 

 beach fill at Presque Isle Peninsula on Lake Erie. Guidelines for moni- 

 toring the effect of shore protection works in the Great Lakes are pre- 

 sented in Coastal Engineering Research Center (1975) . 



Publications discussing wide aspects of Great Lakes shore erosion 

 include State and Federal Government reports, journals, and student theses 

 too numerous to review here. A compilation of published and unpublished 

 data on erosion of the U.S. shoreline was prepared by Armstrong, Seibel, 

 and Alexander (1976) . An atlas by Haras and Tsui (1975) persents data on 

 land use, historic flood and erosion damage, ownership, value, and phys- 

 ical characteristics for all the erodible Canadian shoreline of the Great 

 Lakes. In 1976, the Canadian Government also initiated a 5-year program 

 involving annual and poststorm surveys at approximately 160 stations on 

 the Canadian shore of the Great Lakes. 



II. FIELD METHODS 



1 . Study Area. 



Profiles taken in 1969 near Pentwater Harbor on the eastern shore of 

 Lake Michigan revealed little variation in beach profiles beyond alter- 

 nate ridge-and-runnel development. However, when the 1969 profiles were 

 compared with profiles taken during an evaluation of longshore transport 

 made 2 years earlier, a significant landward shift of the whole active 

 profile became evident. To evaluate the apparent long-term profile 

 evolution, surveys have been repeated at the 10 stations originally es- 

 tablished in 1967 within a kilometer of the Pentwater Harbor (Fig. 3) 

 and also at 24 additional stations spread over adjacent 55 kilometers 

 (Fig. 4). 



2. Survey Periods. 



Profiles are available for six different time periods: (a) summer of 

 1967, (b) spring of 1969, (c) fall of 1969, (d) spring of 1971, (e) fall 

 of 1975, and (f) fall of 1976. Because the frequency of profiling and 

 the extent of the study area changed progressively as previously collected 

 data were analyzed, and the scale of changes was better understood, any 

 given station may have been profiled up to four times during one of the 

 survey periods. Over the years, as the shore continued to retreat, a 

 series of veferenoe monuments was established at most profile stations to 

 provide local control if and when the hase monument at that station was 

 lost. The reference monuments were established above and landward of the 

 original base monuments on the extended range azimuth for that particular 



I I 



