CHAPTER XXIX 

 COST DATA 



IN this chapter are given some examples illustrating the cost 

 of dredging with different types of machines. They are taken from 

 articles published in technical papers, and have been slightly 

 condensed. The following examples are given in order: 



1. The work of the ladder dredge " Percy Sanderson " used at 



Salina, mouth of the Danube River. 



2. The cost of dredging with the hydraulic sea-going hopper 

 dredges " Manhattan " and "Atlantic " as used in the Ambrose 

 Channel, New York, and with the stationary hydraulic dredge 

 used at Wilmington, CaL 



3. The cost of dredging with small dipper dredges used by U.S.A. 

 engineers in the harbors and rivers of different parts of 

 the country. 



4. The cost of dredging with the clamshell dredge " Fin MacCool," 

 used at Buffalo Breakwater, and described by Mr. Emile 

 Low in Engineering News. 



The cost of dredging with the sea-going hopper ladder dredge 

 "Percy Sanderson/' used at Salina, mouth of the Danube River, 

 is taken from a paper by Mr. C. H. Kuhl, M. I. G. E., published 

 in Engineering (London) December, 1901. 



Regarding the cost the quality of the material to be dredged 

 is the most important factor. A shallow cut on an uneven bottom 

 naturally gives very unfavorable results. At Salina, the worst 

 year was 1896, when the cost of dredging, transporting and discharg- 

 ing sand and silt was 5d. per cu.yd. The best year was 1899, when 

 the cost with clay only came to 2. Id. per cu.yd. The average 

 price is 4.2d. per cu.yd. for dredging 1,790,736 cu.yds. from 1894 

 to 1899, including all expenditure for repairs, renewals and liberal 



260 



