wharfs, quays, and similar mooring structures. In relation to OCS primary 

 development, piers are built to service a variety of vessels, including 

 those that carry personnel, equipment, and materials to offshore oil and 

 gas fields, that bring materials (pipe, "drilling mud", etc.) to onshore 

 facilities, and that transport oil or gas. In »"elation to secondary popu- 

 lation growth, piers are built primarily for private recreational craft. 

 Piers may be classified as either "open" piling or column-supported 

 structures, or as "closed" solid-fill structures. 



Disturbances to fish and wildlife resources occur when piers are 

 improperly designed or sited, blocking tidal circulation, preempting 

 wetlands, or disrupting the littoral environment. The construction and 

 long-term disturbances from piers may also have adverse effects, such as 

 pollution from miscellaneous discharges and debris and from bottom scour 

 by boat propellers, bow thrusters, and vessel contact with the bottom. 

 Indirectly, piers may induce dredging and spoil disposal to further 

 facilitate navigation. Existing harbors may be utilized or expanded for 

 deepwater facilities to avoid new pier construction in undisturbed fish 

 and wildlife areas. 



Recently the Corps of Engineers, with cooperation from FWS, has begun 

 to impose environmental constraints on piers in addition to navigational 

 constraints which were traditionally the issue in permit review [43] [44]. 

 Many states also impose environmental requirements. The thrust of these 

 restrictions is (1) to reduce the potential blockage of water flow and 

 decrease in flushing that would be caused by structures, (2) to minimize 

 their encroachment into coastal water areas, and (3) to eliminate as much 

 dredging as possible. 



Location and design of the pier are particularly important factors 

 because they have the strongest influence on the degree to which the pier 

 may block circulation, preempt wetlands, or induce dredging. Once a pier 

 is in place, little can be done except to minimize pollution from boats 

 or dock operations. 



4,2.2 Location 



A new pier location is usually restricted to a particular 

 area because the shore site has already been chosen for reasons 

 of economy, convenience, or availability. Infrequently, a pier 

 proposal may be rejected because minimum ecological safeguards 

 cannot be met. More often, the location would be shifted within 

 the project area to reduce environmental damage. 



The placement of a pier within a site will depend upon a variety of 

 natural and strategic considerations including wave, wind, and current 

 conditions, shore and sea bottom configuration, expected vessel types and 

 traffic, and the shoreside layout and operating plan. To the extent 

 possible, piers should be located in areas that have minimal dredging 



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