basins subjected to large water level fluctuations, flexible hose connections at gangways are 

 often early points of failure in the utiUty -distribution system. Conversion to the hanging 

 U-configuration shown in Figure 102 will prolong the life of such hose connections. 



Valves and washers in hose bibbs require periodic replacement, and an adequate stock of 

 spare parts should be kept on hand. The trend toward greater power consumption 

 frequently overloads the electrical distribution system of a marina. Wherever break -tripping 

 becomes a frequent occurrence, larger capacity wires, outlets, and circuit breakers should be 

 installed. With a large amperage installation, special attention should be given to electrical 

 safety precautions. Slip-renters must be cautioned against the use of undersized or defective 

 extension cords, and a sharp surveillance of all electrical equipment should be maintained to 

 prevent overheating, shorting, or sparking. 



In some saltwater marinas, a high rate of pitting of propeller blades and water-seal 

 bearings has occurred. This may be due to stray currents of low potential but high amperage 

 escaping into the water from the electrical distribution system. An electrical engineer should 

 examine the system to determine and eliminate all probable causes of this electrolysis. 



Vni. MARINA SURVEY AND CASE STUDIES 



1. General. In developing information and data for this report, it was not practical nor even 

 desirable to include every unique design feature encountered in the course of the 

 investigation. Critical response from marina owners and operators, however, can be 

 extremely helpful in evaluating tlie vaUdity of present design concepts, and can also help to 

 pinpoint some of the significant and recurrent problems relating to marina design, 

 development, or management. In an effort to obtain such response and to reveal problems 

 that need greater resolution, a survey was taken of 394 marina owners and operators 

 throughout the 50 States, Washington, D.C., the Virgin Islands, and Puerto Rico. This 

 survey was based on the questionnaire presented in Appendix K. A summary of the 

 survey-sample characteristics and the case studies developed from the data obtained, are 

 presented in this section. The last part of the marina survey questionnaire solicited 

 statements concerning any design feature that had worked better or worse than expected, or 

 any problems that in the operators evaluation could have been avoided by better planning. 

 These statements are also summarized in this section. Several of the concepts mentioned 

 have already been covered to some extent in this report, but are repeated because of their 

 high incidence of occurrence in this survey. 



2. Survey Sample and Data Resolution. About 60 percent of the marinas contacted during 

 the survey were chosen at random from a commercially prepared mailing list. The remaining 

 40 percent were recommended by State agencies as being typical or representative of their 

 respective State, or were selected from various publications such as boating almanacs, 

 boatman's guides, and boating periodicals. Fifty -seven marinas across the United States were 

 visited, with onsite interviews conducted during the visits. 



The size of the faciUties covered by the survey ranged from a six-slip installation for a 

 birdwatching club to a 6,000-boat complex. The average marina size was 255 slips. The 



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