REV00083

• Permit No: C1981071
• IBM Index Class Name: Revision
• Doc Date: 9/1/1993
• Doc Name: SEDIMENT YIELD DEMONSTRATION BLOCK C
• Type & Sequence: SL3
• Media Type: D
• Archive: No

(993 CYVCC - Sediment Yield Drmonrtration • Block C • 8
3.0 RESULTS
The following are the inpu[s and results fora 14year, 24 hour storm event:
BLOCK C SEDIMENT YIELD DEMONSTRATION
INPUTS AND RESULTS
Ana Siz< Tc
(hrz) CN Runoff
Volume
(Y-f[) Peak
Q
(CfS) K Slope
Length Avg.
Slope CP Sedimen[
Yield
([On5)
1 95.1 .171 76 2.5 21.6 .22 500 17 .003 4.3
2 39.J .184 76 I.0 8.7 .22 600 13 .003 I.J
3 30.20 .197 76 0.8 6.5 .22 500 9 .003 0.4
4 8.1 .037 76 0.2 2.8 .22 300 25 .003 0.4
Tonl 172.7 6.4
PASTURELAND REFERENCE AREA SEDIMENT YIELD DEMONSTRATION
INPUTS AND RESULTS
Area Sve Tc
(hrs.) CN Runoff
Volume
(soft) Peals
Q
(cfs) K Slope
Length Avg.
Slope CP Sediment
Yield
(tons)
1 95.1 .171 81 3.8 37.2 .22 500 17 .003 7.5
2 39.3 .184 81 1.6 15.0 .22 600 13 .003 2.2
} }0.20 .197 81 1.2 11.2 .22 500 9 .003 0.7
4 8.1 .037 81 0.3 4.3 .22 300 25 .003 0.6
Total 172.7 11.0
The SEDCAD+ computer printouts are included in Appendix A.
As shown by the SEDCAD+ results, the total sediment load calculated for Block C is less than
the sediment load calculated for [he reference area, indicating that sediment yield from Block
C would contribute less sediment than a comparable adjacent undisturbed pastureland area.
TERRAMATRlX ' P.O. Boz 7740/8 'Steamboat Springs, Colorado 80477 ' (303J 879.6260