improvements. The narrow natural beaches are submerged at high lake 
levels. It has been estimated that about 20 percent of the bluff material 
within the study area is suitable for beach building. Erosion of the 
beach and bluffs along the shore of the city of Cleveland east of Cleveland 
Harbor and in parts of the study area is now supplying considerable beach 
material by means of the slight dominance of eastward littoral drift. 
Beaches west of the study area have been steadily reduced in width by 
erosion during the past 20 years. 
Miscellaneous groins, walls, and breakwaters have been constructed 
in an attempt to prevent erosion of the shore. Short groins have gen- 
erally caused minor accretion on their west sides and have reduced 
recession of the bluffs to some extent, but the majority have been too 
short and low to be fully effective. The accretion west of the outfall 
structure at Euclid City Sewage Disposal Plant and the west jetty at 
the mouth of Chagrin River indicates an eastward predominance of 
littoral drift. 
The mean lake level for the months of March to December is about 
1.6 feet above the established low water datum. The highest lake stage 
and the highest monthly mean recorded at Cleveland, Ohio, are respectively 
about 5.2 and feet above low water datum. Storms cause changes in 
lake levels as winds move the water toward the ends of the lake. Of 
winds which generate waves affecting the area, those from the northeast- 
erly quadrant have the greatest fetch, about 150 miles, but for the ice- 
free period those from the northwesterly quadrant apparently have the 
greater effect on material moverents. It is estimated that, consider- 
ing the effect of wind set-up during easterly storms to be about 1/2 foot, 
the lake could reach a level in the study area of about 4.5 feet above 
low-water datum. During severe storms waves may range up to 10 to 12 
feet in height in deep water, but ordinarily waves of this height would 
break before reaching shore structures. The maximum height of waves 
breaking landward of low water datum shore line at a design lake stage 
of 4.5 above low water datum would be 3.5 feet. Existing groins with 
shore ends from about 5 to 7 feet above low water datum indicate that 
these elevations are generally adequate to impound a low protective beach. 
A beach 30 feet in width between the water line at design lake stage of 
4.5 feet above low water datum and elevation 8 feet above low water datum 
is considered the minimum necessary to protect the bluffs in the study 
area from erosion by wave action. In those areas where a beach presently 
exists, it may be built or maintained to the required minimum dimensions 
by construction of suitably designed groins. However, as more of the 
shore. line is protected the natural supply of beach building material 
through littoral drift may be expected to decrease, and additional 
maintenance by adding material artificially may be necessary. In those 
areas where no beach presently exists and none is desired, the bluff may 
be protected by a seawall with top elevation of 8 feet above low water 
datum and the slope sbove armored with stone revetment to elevation 12 
feet above low water datum. Protection can also be provided by a con- 
tinuous belt of heavy riprap at the toe of the bluff extending up to 
17 
