Qualitative guidance is provided on how and when these estimates should be 

 adjusted to reflect differences in environmental settings. Complete 

 adjustment of the shore will be underestimated by the empirical relationship; 

 but where lake levels change constantly, there will be many such instances of 

 incomplete shore response. (Author). 



133 HANDS, E. B. 1980. "Prediction of Shore Retreat and Nearshore Profile 

 Adjustments to Rising Water Levels on the Great Lakes," Technical Paper 



No. 80-7, US Army Engineer, Waterways Experiment Station, CERC (Coastal 

 Engineering Research Center), Fort Belvoir, VA, pp 119. 



The effects of water level changes on shore recession are particularly 

 important in the Great Lakes because annual mean lake levels often rise 

 rapidly for periods of 5 to 10 years and then decline for a similar number of 

 years. To a limited extent, man can anticipate and influence these fluctua- 

 tions. Two methods of predicting the response of a beach to such fluctuations 

 are (a) by measuring rates of shore change at certain locations during and 

 after a recent rise in the water surface elevations , and assuming the next 

 change in water level will illicit a similar response, or (b) by balancing 

 sediment gains and losses in a number that would adjust an equilibrium profile 

 to the new water level. 



The first method entails a qualitative evaluation of differences in lake 

 level behavior and geomorphic conditions between the study site and the site 

 of application. If mean water levels are predicted to remain at their new 

 elevation long enough for complete profile adjustment, then the second method 

 (sediment balance approach) should be used. The latter approach also accounts 

 for site-specific variations. 



Shore recession in response to higher mean water levels involves adjust- 

 ments which affect a broad area of the nearshore zone. The sediment balance 

 approach provides a realistic model for evaluating the ultimate response of 

 both the shoreline and the nearshore zone to a quasi -permanent change in water 

 levels. This fact was verified by measurements of profile change between 1967 

 and 1976 along a section of the eastern shore of Lake Michigan. This data set 

 also permitted an evaluation of the timelag between lake level changes and 

 profile readjustment. A relationship between the maximum depth of profile 

 adjustment and the wave climate is proposed which will facilitate application 

 of these results to other locations throughout the Great Lakes. (Author). 



134 HANDS, E. B. 1981. "Predicting Adjustments in Shore and Offshore Sand 

 Profiles on the Great Lakes," CETA 81-4, US Army Corps of Engineers, CERC 

 (Coastal Engineering Research Center), Fort Belvoir, VA, pp 25. 



This report summarizes a procedure for calculating the ultimate advance 

 or retreat of the beach profile in response to a semi -permanent change in 

 water level elevation. The method, applicable to sandy shores throughout the 

 Great Lakes, is illustrated by two examples. Hands (1980) describes the 

 development of the procedure. A strictly empirical correlation useful for 

 estimating shore retreat on a 1- to 5-year basis is discussed in Hands (1979). 

 The present procedure couples field measurements with a model of how the 

 profile ultimately reestablishes equilibrium with a new water level elevation. 



63 



