water ballast, but the heavier aggregate materials must be added promptly 

 to obtain further stability. It is assumed that sandfill can be obtained 

 locally without charge by use of a hopper dredge and pumped directly into 

 place without negligible adverse environmental or ecological effects. 

 Rockfill or preplaced aggregate should arrive at the job in self-unloading 

 vessels. Quantities required are large enough to justify bringing in such 

 equipment if not locally available. Riprap toe protection would be placed 

 from barges with a floating derrick, and, since exact placement in such 

 depths is not practical, the cost estimate allows for some overrun. 



f. Miscellaneous . The estimate represents construction contract - 

 prices only, excluding costs of design, inspection, borings, and model 

 tests. 



Costs used throughout the estimate are based on market prices for 

 December 1972. Inflation escalation is suggested at a rate of 5 percent 

 per year to any proposed construction contract date. 



Costs are separated into installation costs and material costs. 

 Material costs are the delivered-on-site cost of all materials, permanent 

 and temporary. All other costs, including such nonlabor items as con- 

 struction equipment charges, towing, and insurance, are installation 

 costs. Labor costs in the estimate include direct payroll and fringe 

 items as benefits, payroll tax, and workman's compensation insurance. 



For making regional adjustments, labor costs amount to slightly over 

 one-half of the total installation cost. Breakwater-site labor is about 

 one-fifth of the total installation cost. 



The total construction schedule may extend over several years, and 

 scheduling construction to avoid as much winter work as possible is 

 advisable. Placing the first unit at the site in the best weather 

 possible is absolutely imperative, since this will be a difficult and 

 exacting operation under the best conditions. 



2. Cost Estimates and Cost Curves. 



a. Basic Estimate . Basic estimate of construction costs for the 

 breakwater structure shown in Figure 1 (8,600 linear feet - 36 units) at 

 a site off Long Branch, New Jersey, in accordance with descriptions and 

 general assumptions discussed previously, is given in Table 2. 



Table 2. Estimated Basic Cost 



Water 

 Depth 



Cost With Oil Storage 

 Capacity 



Cost Without Oil Storage 

 Capacity 



(feet) 



Total 



Per Linear Foot 



Total 



Per Linear Foot 



110 

 90 

 70 

 50 



$653,774,000 

 540,935,000 

 441,635,000 

 281,565,000 



$76,000 

 62,900 

 51,400 

 32,700 



$503,557,000 

 411,524,000 

 340,073,000 

 197.853.000 



$58,600 

 47,900 

 39,500 

 23.000 



46 



