flood stage, the river will usually carry a heavy silt load which remains in suspension only in 

 areas where the current speed is relatively high. This material tends to deposit in the more 

 quiet areas of the watercourse, such as sheltered berthing areas. The best protection against 

 both the debris and shoaling hazards is a training wall. Orientation of the wall will cause 

 floating debris to be deflected away from the entrance and silt deposits will occur in an area 

 that can easily be dredged out after the flood. 



Off-river basins may have minor shoaUng and floating debris problems, but wiU be 

 concentrated at or near the basin entrance. A greater danger is the possibihty of bank scour 

 or overflow of the main river into the basin during a major flood. Tliis has happened a few 

 times, with devasting results (Fig. 156). The best precaution against such an occurrence is to 

 protect the riverbank at and upstream from the basin so that it cannot fail by scour or 

 overtopping in that area. 



g. Vandalism, The looting of boats and maMcious damaging of boats and marina 

 property by vandals is considered both an environmental and a sociological problem. The 

 environment of the harbor site is an important factor to be considered in planning the 

 security measures required. Several suggestions have been made for tightening the security 

 of various harbor components and for fencing the entire installation. Since these measures 

 increase the cost and restrict freedom of action without improving the functional efficiency 

 of the harbor, they should be held to a minimum, and consistent with the nature of the 

 environment and the behavioral pattern of the more antisocial elements of the local society. 

 No set of criteria can be offered to apply in all situations, and every site must be analyzed 

 separately. The best advice is to discuss the problem with local police officials during the 

 harbor planning stage. 



VI. PUBLIC AGENCY PARTICIPATION 

 1. Federal Government. 



a. General. The Federal Government exercises control over navigable waters of the 

 United States and structures buUt in those waters, and maintains certain navigable 

 waterways by periodic removal of shoals and obstructions. The Federal Government also has 

 a number of programs under which the States, their political subdivisions, individuals, 

 groups, and associations may qualify for assistance in developing boating facihties. This 

 assistance involves various degrees of credit, cost-sharing, technical aid, educational services, 

 and research. The purpose of this section is to inform interested parties of the basic 

 provisions of pertinent Federal assistance programs. Details concerning any specific program 

 may be secured from the administrating agency. The headquarters addresses for these 

 agencies are Usted in Appendix E. 



b. Primary Agencies Involved, Authorization, and Programs. 



(1) U.S. Army, Corps of Engineers. This branch of the U.S. Army is responsible, 

 among other things, for the development and maintenance of navigable waterways within 

 the United States. Navigation improvements are authorized by Congress to assist in the 



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