The shore in the vicinity of' Colonial Beach consists of a narrow 

 beach up to about 50 feet in width in front of a bank up to about 20 feet 

 high. The bank is composed of silty sand with some gravelo Much of the 

 bank material is too fine to remain on the beach when eroded from the bank 

 The beach consists principally of sand and gravel with little material finer 

 than fine sand. 



Wave action at times of high river level attacks the bank above beach 

 level causing recession of the shoreline . Over the period of record the 

 shoreline generally receded throughout the area studied , the maximum re- 

 cession amounting to about 300 feet or nearly U feet a year. An exception 

 was the shore at the south end of Colonial Beach where the shoreline ad- 

 vanced over the period of record. From this accretion it appears that the 

 predominant littoral drift is southward although accretion on the south 

 sides of groins during southerly storms indicates that reversals in direc- 

 tion of drift occur o The minor shoaling of the channel into Monroe Creek 

 indicates that the volume of littoral drift is not large 



In attempts to arrest erosion of the bank and to stabilize the beach, 

 local interests have constructed light wooden bulkheads and retaining 

 walls totalling approximately 3,200 feet in length and have also built 

 numerous timber groins. u ,hen in good condition these structures served 

 their intended purpose. At present , parts of the bulkheads and walls and 

 all of the groins are in poor condition. 



The shore area north from Gum Bar Point lving between the State high- 

 way, Riverside Drive, the boardwalk and the Potomac River for a distance 

 of about 10,000 feet i s owned by the town of Colonial Beach and has been 

 dedicated as public beach. Northerly thereof the beach is privately owned, 

 except for the area covered by the 16-foot boardwalk but the public is 

 admitted to the beach in front of the boardwalk without charge. 



The District Engineer considered the desires of the cooperating agency, 

 studied the changes in the shoreline, determined the most suitable methods 

 of protecting the shore against erosion and made an economic analysis of 

 proposed protective measures for the publicly-owned shore. The District 

 Engineer found that the best method of presenting this erosion consists 

 of a stone revetment. He considered that about one-half the frontage re- 

 quires immediate protection and estimated the total cost of the work at 

 $105,000. The District Engi neer considered stabilization of a portion of 

 the beach by a groin system, but found that the beach can be preserved at 

 lower cost by artificial replenishment as required. 



The District Engineer recommended that a project be adopted by the 

 United States authorizing Federal participation, subject to certain condi- 

 tions of local cooperation, in an amount equal to one-third the cost of 

 the protection of the shore at Colonial Beach, Virginia, which comprises 

 the construction of 7,350 linear feet of stone revetment along the State 

 highway, about one-half of which he recommended for initial construction 

 and the remainder as deferred construction. The Division ISngineer concur- 

 red in the conclusions and recommendations of the District Engineer,, 



The Board carefully considered the reports of the reporting officers „ 

 It concurred in their views and recommendations. The shore along the State 

 highway is receding. Part of this shore needs immediate protection. The 

 remainder will probably need protection in the future. The most suitable 



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