WSP08407

• File Number: 8270.100
• Description: Colorado River Basin Water Quality/Salinity -- Misc Water Quality
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 10/1/1983
• Title: Colorado River Water Quality Improvement Program - Big Sandy River Unit - Draft Planning Report/Advance Draft Environmental Impact Statement - October 1983
• Water Supply Pro - Doc Type: EIS

.

.

.

<;>
~
Q
f\)

CHAPTER I

INTRODUCTION

inches on the higher benches near the Wind River Mountains in the north

and east. Peak precipitation months are April, May, and June. Snowfall

can occur as early as September and as late as July, but more commonly

from October to May.

A snow cover generally remains on the ground

during the winter months.

Average temperatures at Farson vary from a low of 90 F in January

to a high of 630 F in July.

Extreme temperatures vary from _550 F in
,

the winter to above 900 F in the summer. The growing season may begin

as early as May 1 and extend as late as October 1; however, it averages

only 90 days.

Vegetation in the area is primarily influenced by precipitation,

soil condition, and land use.

Sagebrush-grass is the major vegetation

type in the unit area, including big sagebrush, rabbitbrush, black sage,

several species of grass, and numerous small broad-leaved forbs.

Nuttall saltbush, shadscale and black greasewood replace sagebrush as

the dominant shrub species in the flatter terrain at lower elevations

where saline or alkaline soil conditions prevail.

Vegetation along the Big Sandy River and the numerous seeps

receives additional moisture from streamflows, creating a narrow zone of

riparian vegetation and associated meadows along these areas.

This

wetland is characterized by willow, shrubby cinquefoil, Nuttall salt-

bush, silver sagebrush, and black greasewood.

In general, the overall range condition for the area is considered

only fair for cattle and sheep but good for pronghorn antelope and mule

deer.

5