Harbors 



areas, notably Venice, San Pedro, Long 

 Beach, Newport Beach, and Coronado, sed- 

 iment has been pumped to the beach from 

 nearby lagoon floors. These replenishment 

 actions fall far short of the 2,400,000 cu 

 meters annually contributed by streams, but 

 they are approximately equal to the amount 

 of beach sand trapped by artificial structures. 

 Thus we might expect the beaches to re- 

 main except for local and intermittent losses. 

 Unfortunately, however, the character of 

 the beaches made by artificial dumping is 

 diff'erent from that of the original natural 

 beaches. For example, the artificially 

 nourished beaches at Santa Monica Bay 

 and Newport Beach have been built so far 

 seaward that their foreshores are steep and 

 waves break almost at the shore, spoiling 

 the areas for swimming. Diff'erences in 

 grain size of the original beaches and the 

 ones artificially formed of dune sand and 

 lagoon floor sediments have also locally 

 produced steeper than normal slopes. 



The second method of keeping beaches is 

 that of building groins, structures normal to 

 the beach. Some of these are of rock, and 

 others are of wood or steel piling. All in- 

 tercept the longshore flow of sand and thus 

 cause its deposition. However, this same 

 interception creates a steadily worsening 

 beach situation at their lee so that ever 

 more expensive measures are required. 

 Basically the problems of narrowed beaches 

 are related to the construction of boat har- 

 bors in places where nature never intended 

 them to be. The best-situated artificial har- 

 bor of the entire coast is that at Redondo 

 Beach located near the head of a submarine 

 canyon toward which sand moves along 

 beaches both from north and south. Any 

 sand that it intercepts would have been lost 

 to the canyon anyway. Other favorable 

 places, at least so far as beach sand losses 

 are concerned, are around the Palos Verdes 

 Hills, at Laguna, La Jolla, and Point Loma. 

 The suitability of these sites was recognized 

 by nature because natural harbors occur 

 near several of the sites, obviating the need 

 for artificial harbors there. By the same 

 token, the two worst-situated artificial har- 

 bors, with respect to down-beach losses, are 



315 



doubtlessly Santa Barbara and Santa Mon- 

 ica, but the population pressure in both areas 

 may justify their existence. 



Harbors 



Harbors can be classified into five main 

 types, commercial, military, recreational, 

 fishing, and refuge (Peel, 1951). The two 

 largest harbors of southern California, Los 

 Angeles-Long Beach and San Diego, are 

 used for all five purposes. The harbors of 

 intermediate size, Santa Barbara, Port 

 Hueneme, and Newport Bay, are used for 

 most of them. Smaller ones are less versa- 

 tile with Anaheim Bay and Camp Pendle- 

 ton chiefly military, and Santa Monica, 

 Play a del Rey (under construction), Redondo 

 Beach, Alamitos Bay, Sunset Bay-Bolsa 

 Chica, and Mission Bay chiefly recreational, 

 and most of the ones around the islands are 

 used chiefly for refuge. Most of the harbors 

 used chiefly for recreation are of artificial 

 origin or at least have been extensively 

 modified by man. Except for the largest 

 cities, the population centers of southern 

 California formed independently of harbor 

 facilities; later, when recreational needs 

 arose, small harbors had to be built to serve 

 the need. Thus the large cities developed 

 because of the presence of large harbors, 

 but many of the small recreational harbors 

 developed because of the presence of cities. 

 Because of increased interest in boating, ad- 

 ditional harbors are being considered at 

 Goleta Lagoon, Carpinteria Lagoon, Point 

 Dume, Malibu Lagoon, Malaga Cove, Por- 

 tuguese Bend, Dana Point, Agua Hedionda 

 Lagoon, San Elijo Lagoon, Batiquitos La- 

 goon, and Imperial Beach. 



As pointed out in the previous section, 

 some of the smaU harbors are weU placed to 

 intercept the longshore drift of beach sands 

 with consequent narrowing of beaches at 

 their lee. At the same time, the intercepted 

 sediments serve to block the entrances of 

 harbors such as Santa Barbara, Port 

 Hueneme, Anaheim Bay, and Mission Bay 

 and to fill the interior of ones such as Santa 

 Monica Harbor (Fig. 240). Both processes 

 decrease the usefulness of the harbors and 



