2. Planting Costs . 



a. Site Preparation . Sites which have little likelihood of being 

 successfully stabilized can be modified to improve their suitability. The two 

 primary methods of improving a site are: (1) grading of the beach face or (2) 

 constructing a wave-stilling device. 



( 1 ) Grading the Beach Face . Grading the beach face can increase the 

 width of the area available for planting and the distance over which wave 

 energy will be dissipated. This will usually improve the chances for success- 

 ful plant establishment. The following is an estimate of the costs required 

 to create a 1 on 15 slope in front of a 1-meter-high bank (adapted from 

 Eckert, Giles, and Smith, 1978): 



Method Cost per cubic meter Cost per linear meter 



Dredge (hydraulic $4.50 $33.75 



placement) 



Dump-truck placement 9.00 67.50 



These values were calculated assuming: (a) there is easy access to the 

 work site, (b) the fill material is within a reasonable distance to the work 

 site, (c) all construction is in an area of low to moderate wave climate, (d) 

 grading is included in the estimate, and (e) the hydraulic dredge is used for 

 only large projects in excess of 1000 linear meters. 



(2) Wave-Stilling Devices . Wave-stilling devices are used to protect 

 the planting from severe wave impact. These can be very helpful in protecting 

 plants through the critical establishment period. The following is an esti- 

 mate of the cost of constructing two low-cost wave-stilling devices: 



Method Cost per linear meter 



Rubber tire breakwater (two tires $25 (adapted from Webb and 

 high, labor included M Dodd, 1978) 



Sandbag dike breakwater (1 meter $100 (adapted from Eckert, 

 high with filter cloth included) Giles, and Smith, 1978) 



^ Labor is estimated at $30 per man-hour ($15 per man-hour direct 

 costs plus 100 percent overhead) . 



b. Harvesting, Processing, and Planting . The labor required to acquire 

 or produce propagules and to plant is the principal cost of a project unless 

 site preparation or temporary protection is required. Labor demands vary 

 widely with species, availability of plants and seeds, type of propagule, 

 accessibility of the site, soil type, size of operation, and degree of 

 mechanization used. Working hours in the intertidal zone are controlled by 

 tidal regimes. Both harvesting and planting are usually confined to about a 

 5-hour period per tide. This restriction requires careful coordination for 

 efficient operation and often adds substantially to the cost. 



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