FACTORS AND TABLES OF EQUIVALENTS USED IN FORESTRY 23 

 Table 39. — Discharge of water: conversion of second-feet to runoff in acre-feet 1 



Second-feet 









Period in day 



s 









1 



5 



10 



15 



20 



28 



29 



30 



31 



1 



1.98 

 3.97 

 5.95 

 7.93 

 9.92 

 11.90 

 13.88 

 15.87 

 17.85 



9.92 



19.83 

 29.75 

 39.67 

 49.59 

 59.50 

 69.42 

 79.34 

 89.26 



19.83 

 39.67 

 59.50 

 79.34 

 99.17 

 119.01 

 138. 84 

 158. 68 

 178. 51 



29.75 

 59.50 

 89.26 

 119.01 

 148. 76 

 178. 51 

 208. 26 

 238. 02 

 267. 77 



39.67 

 79.34 

 119.01 

 158. 68 

 198. 35 

 238. 02 

 277. 69 

 317. 36 

 357. 02 



55.5 

 111.1 

 166.6 

 222.1 



277.7 

 333.2 

 388.8 

 444.3 

 499.8 



57.5 

 115.0 

 172.6 

 230.1 

 287.6 

 345.1 

 402.6 

 460.2 

 517.7 



59.5 

 119.0 

 178.5 

 238.0 

 297.5 

 357.0 

 416.5 

 476.0 

 535.5 



61.5 

 123.0 

 184.5 

 246.0 

 307.4 

 368.9 

 430.4 

 491.9 

 553.4 



2 



3 



4 



5 



6 





8 



9 





1 1 second-foot is equivalent to 1.98347 acre-feet. 



Table 40. — Discharge of water: conversion of second-feet per square mile to runoff 

 in depth in inches over the area 1 



Second-feet per 

 square mile 









Period in 



days 









1 



5 



10 



15 



28 



29 



30 



31 



1 



0. 03719 

 . 07438 

 .11157 

 . 14876 

 . 18595 

 . 22314 

 . 26033 

 . 29752 

 . 33471 



0. 18595 

 . 37190 

 . 55785 

 . 74380 

 . 92975 

 1. 11570 

 1. 30165 

 1. 48760 

 1. 67355 



0. 3719 



.7438 

 1. 1157 



1. 4876 

 1.8595 



2. 2314 

 2. 6033 



2. 9752 



3. 3471 



0. 5579 

 1.1157 



1. 6736 



2. 2314 



2. 7893 



3. 3471 



3. 9050 



4. 4628 



5. 0207 



1.041 

 2.083 

 3.124 

 4.165 

 5.207 

 6.248 

 7.289 

 8.331 

 9.372 



1.079 



2.157 

 3.236 

 4.314 

 5.393 

 6.471 

 7.550 

 8.628 

 9.707 



1.116 



2.231 

 3.347 

 4.463 

 5.579 

 6.694 

 7.810 

 8.926 

 10. 041 



1.153 



2.306 

 3.459 

 4.612 

 5.764 

 6.917 

 8.070 

 9.223 

 10. 376 



2 



3 - 



4 



5 



6 



7 



8 



9 





1 1 second-foot per square mile is equivalent to 0.03719008 inch in depth per day. 



Table 41. — Inches depth in terms of approximate volume per unit area 1 



Inches 

 depth 



Cubic 



feet per 



acre 



Cubic 



yards per 



square 



mile 



Inches 

 depth 



Cubic 



feet per 



acre 



Cubic 



yards per 



square 



mile 



0.01 



36 



860 



0.24 



871 



20, 651 



.02 



73 



1,721 



.25 



908 



21,511 



.03 



109 



2,581 



.26 



944 



22, 372 



.04 



145 



3,442 



.27 



980 



23, 232 



.05 



182 



4,302 



.28 



1,016 



24, 092 



.06 



218 



5,163 



.29 



1,053 



24, 953 



.07 



254 



6,023 



.30 



1,089 



25,813 



.08 



290 



6,884 



.33 



1,198 



28, 395 



.09 



327 



7,744 



.35 



1,270 



30, 116 



.10 



363 



8,604 



.40 



1,452 



34, 418 



.11 



399 



9,465 



.45 



1,634 



38, 720 



.12 



436 



10, 325 



.50 



1,815 



43, 022 



.13 



472 



11,186 



.55 



1,996 



47, 324 



.14 



508 



12, 046 



.60 



2,178 



51, 627 



.15 



544 



12, 907 



.65 



2,360 



55, 929 



.16 



581 



13, 767 



.70 



2,541 



60, 231 



.17 



617 



14, 628 



.75 



2,722 



64, 533 



.18 



653 



15, 488 



.80 



2,904 



68, 836 



.19 



690 



16, 348 



.85 



3,086 



73, 138 



.20 



726 



17, 209 



.90 



3,267 



77, 440 



.21 



762 



18, 069 



.95 



3,448 



81, 742 



.22 



799 



18, 930 



1.00 



3,630 



86, 044 



.23 



835 



19, 790 









1 Inches depth multiplied by 3,630 gives the number of cubic f 

 by 86,044.44 gives the number of cubic yards per square mile to 



et per acre to a depth of 1 inch: multiplied 

 depth of 1 inch. 



