One alternative to the harbor is 

 the upland storage of small craft. This 

 can either be accomplished by the indi- 

 vidual owner retaining possession of the 

 craft or a central storage facility being 

 constructed. Such a facility would nor- 

 mally be near a launching point. A 

 means of launching is required before 

 upland storage is a viable alternative. 

 A ramp for use by trailer mounted craft 

 is most commonly used, but a crane sys- 

 tem mounted on a pier is also feasible. 

 The main constraint of upland storage 

 is that it is time consuming. It is also 

 quite expensive to launch larger ves- 

 sels. Upland storage is generally an 

 alternative for small craft which trailer 

 easily. 



Alternatives for the larger vessels 

 are individual piers or mooring buoys 

 located in protected areas. Generally, 

 a single well-placed boat harbor would 

 be a preferable alternative to a prolif- 

 eration of single moorages, but such a 

 decision can only be made after a site 

 examination. 



Placement of small craft harbors 

 inland of wetlands and tidal zones, with 

 access by a dredged channel, may pre- 

 sent a desirable alternative as far as 

 location is concerned. Again, all bio- 

 logical, economic, and navigation factors 

 must be weighed to make such a deter- 

 mination. 



Regional Considerations 



Most of the information in the lit- 

 erature can be applied to all the coastal 

 regions. There are some considerations, 

 however, that were mentioned in refer- 

 ence to particular coastal regions. The 

 effect of small craft harbors on salmon 

 migration was studied in the north Paci- 

 fic (Coastal Region 1). This information 

 may also be applicable to the Great 

 Lakes (Coastal Region 8) where salmon 

 have been introduced. Salmon fry will 

 not go through culverts, so it is recom- 

 mended that gaps be provided in break- 

 waters or other structures to allow the 

 passage of salmon fry to all tidal levels 

 without forcing the fry to enter water 

 over 1 ft (C.3 m) deep where predation 

 may be increased (Heiser and Finn 

 197C). 



Only 10% of California coastal wet- 

 lands (Coastal Regions 1 and 2) remain 

 and much of the loss is attributed to 

 marinas (Slawson 1977). California laws 

 can prevent most wetland development, so 

 marinas are now being built on uplands 

 with canals leading to the open water 

 (Carlisle 1977). 



There have been heavily contested 

 proceedings over the construction of 

 marinas and marina/residential develop- 

 ments in Florida (Coastal Regions 3, 4, 

 and 5) . 



BRIDGES AND CAUSEWAYS 



Definition 



A bridge is a structure erected to 

 span natural or artificial obstacles, 

 such as rivers, highways, or railroads. 

 A bridge supports a footpath or roadway 

 for pedestrian, highway, or railroad 

 traffic (Figure 49). A bridge normally 

 is built from steel, concrete, or wood. 

 Bridges are supported by piers and abut- 

 ments. A bridge pier is a support struc- 

 ture in the water and should not be con- 

 fused with other marine structures of 

 the same name which serve as a landing 

 place for boats. An abutment is the 

 structure supporting the bridge at the 

 point where the land meets the water as 

 distinguished from a pier which is whol- 

 ly in the water. 



A causeway is a way of access, or 

 raised road, typically across marshland 

 or water (Figure 50). A causeway nor- 

 mally consists of a continuous solid 

 fill embankment constructed of earth, 

 sand, or rock dredged or dumped in the 

 water or on marshy land with a roadway 

 or pathway on it. A causeway can have 

 culverts on open channels to allow cir- 

 culation and equalization of the water 

 heights on both sides of the structure. 



Structure Functions 



The basic function of both bridges 

 and causeways is to support some form of 

 land transportation, such as foot traf- 

 fic, highway, or railroad tracks. Where 

 the obstacle to be crossed is water or 

 marshy land, either structure can per- 

 form the function satisfactorily. The 



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