developing offshore of the revetments. Slight scour is evident at the toe of the armor stone 

 some distance around each island with slight accretion of sand away from the islands (U.S. 

 Army Engineer District, Norfolk, 1971). 



In addition, scour has been noted along the line of the trestle extending from each island 

 (Sverdrup and Parcel, 1972). 



The extent of scour both in area and depth has varied at each island, but has generally 

 been centered on the fifth or sixth trestle bent off the island. A close check has been kept 

 on the extent of scour at each island. The scour to the north of the northernmost island has 

 been by far the most severe of the four areas and remedial action has been taken here in the 

 form of dikes and riprap. 



Figure 5 shows scour conditions and a comparison of recent soundings with original 

 bottom contours at Island No. 4. For further comparison, the approximate depth of scour 

 at each island, according to similar records is as follows: Island Nos. I, 8 feet; 2, 8 feet; 3, 

 II feet; and 4, 20 feet. 



Sport fishing and small boat activity, the crossing in general and the islands in particular, 

 have contributed greatly to the recreational activity in the area. The biota is discussed in the 

 following paragraph. The psychological effect of having the structures available for 

 emergency protection has increased small boat activity across the mouth of Chesapeake Bay. 



(2) Biota (U.S. Army Engineer District, Norfolk, 1973). The islands, constructed 

 with open rock faces, provide a habitat for numerous types of sea plants and animals. The 

 naturally protected areas between the rocks attract large quantities of small fish, shellfish 

 and crabs. These small fish in turn provide a food supply for the larger species which gather 

 at the islands in great numbers. 



Lacking a specific count of fish in the area before construction makes it impossible to 

 determine quantitatively the increase in fish population. However, in the opinion of local 

 sport fishermen, the number and variety of fish have greatly increased. 



Construction of a fishing pier off Island No. 1, provides an opportunity for local 

 fishermen and travelers to take advantage of these conditions. 



Wildlife presently in the area are Usted in Tables I and 2 (U.S. Army Engineer District, 

 Norfolk, 1973). 



(3) Aesthetics. While obviously affecting the view across the mouth of Chesapeake 

 Bay, the need for the crossing and the effort expended on its overall appearance have 

 resulted in general acceptance including ASCE designation as "The Outstanding Engineering 

 Achievement— 1 965. " 



i. Engineering. Sverdrup and Parcel, Consulting Engineers, 915 OUve Street, St. Louis, 

 Missouri 63101. 



j. Construction Contractors (joint venture). Tidewater Construction Corporation, P.O. 

 Box 57, Norfolk, Virginia 23601 (Sponsor); Merritt-Chapman and Scott Corporation, New 

 York, New York lOOOI (discontinued operations); Raymond International Incorporated, 



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