Several types of natural bays present a deceptive first impression to harbor siting. The 

 first type is a natural bay protected by an offshore spit on an open coast. Many of these 

 bays along the Atlantic and gulf coasts appear quite fragile, but provide excellent sites for 

 small-craft harbors. Sounds, on the other hand, appear to provide excellent harbor sites 

 because they offer protection from high waves approaching from open waters. However, 

 their great lengths usually are conducive to high, locally generated wind waves and possible 

 resonance with waves (seiching), which can result in extreme ranges of water level 

 fluctuations. Many sounds are too deep and anchorage of slips and docks becomes a severe 

 problem. Where a sound is located between headlands and is narrow like a fjord, perimeter 

 lands often rise abruptly from the water, and access routes and provision of adequate land 

 area for supporting a harbor complex become critical factors. 



5. Roadsteads. A good site for a small-craft harbor may often be found close to the open 

 ocean in an area that is shielded from the prevailing ocean waves by natural terrain features. 

 An example is a bight in the shoreline behind projecting headlands (Fig. 5). Site selection 

 here must include consideration of occasional wave episodes from directions other than 

 those of the normal wave regime and from which the site is exposed. Studies of wave 

 refraction may be needed to ensure that open-sea swell from certain offshore directions does 



Figure 5. Port San Luis, Cahfornia. A typical harbor in a roadstead. This site is protected 

 from the prevailing westerly waves but is exposed to occasional high wind waves 

 from the south. 



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