WSP04023

• File Number: 8272.600.60
• Description: Colorado River Basin Salinity Control Program - Basin Member State Info - Utah
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 7/1/1990
• Title: Upper Colorado River Basin Rangeland Salinity Control Project
• Water Supply Pro - Doc Type: Report/Study

I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I

N
N
.."'-
en

Present and FWOP condition sediment yield rate is approximately
1.9 acre-feet per square mile or approximately 5.7 tons per acre
(PSIAC sediment yield classification 2 - high). The annual FWP
condition is estimated at approximately 0.5 acre-feet per square
mile or 1.5 tons per acre (PSIAC sediment yield classification 2-
3 - moderate to moderately high). Proposed project measures
include harrowing or plowing on the contour around existing
drainages, grazing management and seeding to lengthen and disturb
the well developed concentrated overland flow paths.
Implementation of the proposed treatment will result in the
annual control of 6790 acre-feet or 20,370 tons of sediment and
the saving of 3056 tons of salt. The salt yield rate is
estimated at 15%. This unit is recommended for project level
land treatment planning.

unit 3 - UPPER WATERSHED - This unit contains the Wasatch
Formation and the Mesaverde Group which are composed of
sandstone, siltstone and some shale. This area is highly
dissected and is characterized by steep and deep canyons. The
canyon sides are partially vegetated and stable. The unit
contains approximately 26,844 acres. Present condition and FWOP
annual sediment yield rates from this area are approximately 0.53
acre-feet per square mile or approximately 1.5 tons per acre
(PSIAC sediment yield classification 3 - moderately high). The
estimated salt yield rate is 2%. The estimated sediment yield
from this unit is 10,738 acre-feet or 32,214 tons and the
estimated salt yield is 644 tons. This unit has significant
acreages of exposed resistant rock and armored steep slopes.
There is no need for conservation measures in this unit.

unit 4 - BADLANDS - This unit is characterized by badland
topography. The steep Mancos Shale slopes underlie resistant
sandstone layers of the Mesaverde Group. The unit contains
approximately 5241 acres. Sediment yield from this area is in
the high and severe range. The rapid erosion rates
characteristic of this unit are the result of natural geologic
erosion processes. It is estimated that 50% of the acreage in
this unit is actively involved in the sediment yield process.
The other 50% is stabilized by exposed resistant rock or by rock
armor covering the slope. The area is a naturally high sediment
and salt yielding zone. The Present condition annual sediment
yield rate was estimated in various places within the unit.
Estimates varied between 5.7 to 8.0 acre-feet per square mile or
between 17.1 to 24.0 tons per acre. The estimated salt yield
rate is 15%. The estimated average annual sediment yield for
this unit is approximately 6.0 acre feet per square mile or 18
tons per acre (PSIAC sediment yield classification 1 - very high
or severe). The estimated annual sediment yield from this unit
is 25,130 acre-feet or 75,479 tons. The estimated annual salt
yield is approximately 9959 tons. This area is NOT recommended
for project-level land treatment planning (see Badland Debris
Basin section of this report).

11