Prefeasibility Access Road Design-Revised
27
Warren Peak Hydraulic Data
WS
#
Required
Flow (cfs)
Number of
Culverts
Culvert Size
in.
ft
1
227
1
84
7.0
2
373
1
96
8.0
WS
#
Culvert
Length
(ft)
Station
US
Invert
Elev.
DS
Invert
Elev.
Road
Elev.
HW
Elev.
Cover
Free-
board
1
511
134+45 5452.9
5411.9
5508.8 5459.9
7.0
48.9
2
372
139+95 5445.3
5410.1
5476.0 5453.3
8.0
22.7
IX
DISTURBANCE AREAS
Areas of disturbance have been estimated for each landowner that will be affected
by the roadway construction. These areas do not include any area already disturbed
by the existing 66’ ROW. The existing ROW was followed where possible to
minimize the disturbance area. The disturbance areas are calculated using the
typical section developed for this phase of design.
X
BLOWING SNOW ANALYSIS
A blowing snow analysis was performed on the typical section that was chosen for
the project. The snow analysis was performed using WYDOT methods. In open areas
where wind blown and drifting snow can close roadways, a section using 6:1 slopes
from the shoulder down to a 10 foot wide flat bottomed ditch was utilized. The back
slopes were also 6:1. These gentle slopes are safe for errant vehicles, provide room
for snow storage and meet the criteria to mitigate blowing snow.
In timbered areas, blowing snow is not as much of a problem as snow storage. The
trees act as shelter areas and mitigate the problem of blowing and drifting snow.
The bigger problem for this project is the timbered areas, which are likely to be
rocky and steep. Cuts in this area will hold falling snow. To mitigate this snow
storage issue, the section will use a 6:1 slope from the shoulder down to a 20 foot
wide flat bottomed ditch. The back slope in this area will range from a 2:1 to 4:1
depending on the depth of cut. The slopes are gentle and forgiving to traffic inside
