of wetlands. These must be considered during the location, design, 

 construction and operation of the facility. 



Location : With ships, boats, and drilling rigs needing mainte- 

 nance on a regular schedule and occasionally needing emergency repairs, 

 a facility is usually located in a sheltered channel or harbor. This 

 allows easy access for vessels and gives the protection from the 

 open ocean necessary during repairs. Location at the mouths of bays 

 and estuaries would aid the flusing and dispersion of silts stirred by 

 boat and mobile-rig propellers and of petroleum discharges from engines. 

 Channels and harbors that require little initial and maintenance dredging 

 should be considered as the best choices for the location of facilities. 



Design : Repair and maintenance facilities should be placed on 

 existing waterfront property to reduce adverse effects on fish and 

 wildlife. This would avoid the loss of fish and wildlife habitat 

 by the filling of wetlands. 



The need for dredging navigable channels and a turning basis will 

 cause problems of turbidity and sedimentation, which may lead to the 

 smothering of clams, corals, and other organisms. Oxygen depletion is 

 also associated with dredging. Channels should be designed to limit the 

 amount of initial and maintenance dredging. The channel route should be 

 the shortest distance to the facility for dredging with minimum disruption 

 of fish and wildlife habitat. Also to be considered is the type of 

 bottom material, with loose, unconsolidated material requiring maintenance 

 dredging more often. 



Floating dry docks should be utilized where feasible instead of 

 excavated dry docks. Floating dry docks reduce the need for excavating 

 wetlands; such excavation leads to reduced aquatic productivity and loss 

 of breeding/rearing areas. 



Construction : Open pile piers and floats should be built instead 

 of sheet steel bulkheads. In the construction of steel bulkheads for 

 the repair of boats, shores are often dredged to create a berth and to 

 obtain fill to place behind the bulkhead. This alters the natural 

 configuration of the shoreline and robs areas down the shore of needed 

 sand by interrupting littoral drift. In addition, solid-fill structures 

 tend to intercept, divert, and disperse water currents. This diversion 

 decreases available food supply and changes water parameters, such as 

 salinity, oxygen, etc., leading to a significantly altered fish and 

 wildlife habitat. 



Operation : When repairs are being conducted on ships and rigs in 

 the facility, all vessels should be inspected to prevent any unnecessary 

 oil and grease losses. Vacuum trucks and other skimming devices should 



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