2021-04-05_PERMIT FILE - C1981019A ‎(19)‎

• Permit No: C1981019A
• IBM Index Class Name: Permit File
• Doc Date: 4/5/2021
• Doc Name: West Taylor Pond and Channels
• Section_Exhibit Name: Exhibit 07 Item 20 Part B -ST
• Media Type: D
• Archive: Yes

West Fork Taylor Ditch
Peak Minimum
Average Channel Erosion
Station Flow ° Side Slopes Depth
CFS Sloe /o Type Feet Protection
Station 0+00 to 2748 26 3H:1V 4
Trapezoidal Riprap,
WFSP-1 . 12' bottom .0 D50 = 9"
WFSP-1 to 46.52 1.3 Trapezoidal 3HAV 4.0 Vegetation
WFSP-2 12' bottom
WFSP-2 to 72.61 1.5 Trapezoidal 3HAV 4.0 Vegetation
Station 40+00 12' bottom
Station 40+00 to 2685 8 Trapezoidal 3H:1 V 4.0 Vegetation
83+05 12' bottom
Tributary Ditches
The six post mine tributaries channels (Trib's 1 through 6) will be constructed to break up long
continuous slopes and minimize erosion in the South Taylor reclamation areas. They will also
convey flow to the two primary channels. These six tributaries were modeled in accordance with
Rule 4.05.3(3) for the 10-year 24-hour event.
A very small portion of Trib 1 flows over a permanent fill, which in accordance with Rule
4.09.2(7) makes the appropriate storm event for this small portion of channel the 100-year, 24
hour storm event. Since it is minor portion of the channel flows over permanent fill, Trib 1 is
modeled to the 10-year, 24-hour storm event.
A summary of the configurations for each tributary channel is provided on the table below.
Post Mine Tributary Channels
Peak Average Channel Minimum Erosion
Tribuary Name Flow Sloe % Type Side Slopes Depth Protection
CFS Feet
Trib 1 9.76 5.0 Trapezoidal 3HAV 2.0 Vegetation
6' bottom
Trib 2 5.26 11.0 Trapezoidal 3HAV 2.0 Vegetation
6' bottom
Trib 3 0.11 11.0 Trapezoidal 3H:1V 2.0 Vegetation
6' bottom
Trib 4 0.05 16.0 Trapezoidal 3H:1 V 2.0 Vegetation
6' bottom
Trib 5 0.09 4.0 Trapezoidal 3H:1 V 2.0 Vegetation
6' bottom
Trib 6 0.15 6.0 Trapezoidal 3HAV 2.0 Vegetation
6' bottom
Exh. 7-20B-3 Revision Date: 1/20/21
Revision No.: TR-145