FLUMES AND LOG SLUICES 409 



The cost of engineering work is from $100 to $140 per mile; 

 and the cost of construction, including labor, material and right- 

 of-way, from $1000 to $3000.^ 



Labor on flume construction averages from 30 to 40 cents 

 per hour for men who work aloft and from 25 to 27I cents for 

 ground men. 



The number of days' labor, the pounds of nails and the thou- 

 sand board feet of lumber required to build trestles- of specified 

 heights and of the types shown in Figs. 125 and 126 is given in 

 the preceding table. 



The construction of the box and foot-boards required 68,485 

 board feet of lumber and approximately 2800 pounds of nails, 

 per mile. The cost of box construction averaged $320 per 

 mile. 



The average cost of short lumber flumes where high trestles 

 are not required and no special difficulties attend the work, 

 does not exceed from $1200 to $1400 per mile; log flumes cost 

 from $6000 to $8000 per mile; and log sluices from $2000 to 

 $4000. On the other hand certain sections of a flume built in 

 the Big Horn mountains of Wyoming for bringing out crossties, 

 mine timbers, and lumber cost $9000 per mile for four miles, 

 and $5000 per mile for an additional five miles. The high 

 cost of construction was due to the difficult engineering prob- 

 lems involved, including the construction of two tunnels, heavy 

 trestles and the building of the flume along the precipitous 

 sides of gorges. 



Several box and V-flumes,^ in California, which extend for 

 distances of from 50 to 70 miles, have cost $5000 and upward 

 per mile. 



1 See Lumber Flumes, by Francis R. SteeL Bulletin of the Harvard Forest 

 Club, Vol. I, 1911. 



- Designed by F. A. Kettenring, C. E. Vancouver, Washington. 



' A V-flume with 36-inch sides and a width across the top of 46 inches was built 

 in 1899-1900 in California, by the Madera Sugar Pine Company. The flume was 

 originally 53I miles in length and cost $275,000 to construct, an average of $5000 

 per mile. Appro.ximately 5,700,000 feet of redwood lumber and 2100 kegs of nails 

 were used in construction. The maximum grades were 18 per cent and lumber 

 traversed the flume at the rate of 6 miles per hour. The daily capacity is appro.xi- 

 mately 100,000 feet. 



