The Beaver Creek Experimental Watershed is located between latitudes
34° 30' and 35° north, and 111° 30' to 112° west
longitude in north-central Arizona. The center of the watershed is about
80 km (50 mi) south of Flagstaff, Arizona, in Coconino and Yavapai Counties.
Established in 1956 by the USDA Forest Service as a major center for watershed
management research within the pinyon-juniper and ponderosa pine vegetation
types, the site encompasses 111,375 ha (275,000 ac) on the Coconino National
Forest.
Location of watershed in the state
It is located upstream from the junction of Beaver Creek and the Verde
River in north-central Arizona. This watershed is part of the Salt-Verde
River Basins, which are major river drainages in central Arizona and provide
much of the domestic and agricultural water for Phoenix and other communities
in the heavily populated Salt River valley. The Beaver Creek watershed
lies along the Mogollon Rim and is within the largest continuous stands
of ponderosa pine in the United States, which extends as a belt of trees
for nearly 200 miles across Arizona.
Location in the Salt-Verde River Basin
In ascending order of elevation, the three vegetation types found on
the Beaver Creek watershed are: semi-desert
shrubs, pinyon-juniper (including alligator juniper and Utah juniper subtypes), and ponderosa
pine.
Semi-Desert Shrub
Pinyon-Juniper
Ponderosa Pine
The Beaver Creek Experimental Watershed was established in 1956 to study
the influence of various vegetative manipulations of pinyon-juniper and
ponderosa pine on water yield and to evaluate changes in livestock forage,
timber production, wildlife habitats, recreational values, and soil movement.
A paired watershed approach was used to evaluate treatment responses.
Two watersheds with similar characteristics, both physical and biological,
were selected and measurements of streamflow, sediment production, water
quality, vegetation, and animal use were made on each watershed before
any treatment was applied. After a period of time, one watershed was selected
for application of a management treatment and measurements continued on
both the treated and control watersheds. Changes caused by management
practices applied to the treated watersheds were evaluated by comparing
post treatment values with pretreatment data, and with data from the control
watersheds. All water-oriented studies on Beaver Creek were terminated
by 1982, and final results of the initial treatment studies were reported
on during the latter part of the 1980s.
Aerial view of Beaver Creek area
Interstate Highway I-17 crosses the area, linking Flagstaff and Phoenix,
Arizona. General access within the watershed is good, although it is by
unpaved Forest Service roads. Because the surrounding land is within the
National Forest, there is complete administrative control over the entire
experimental watershed with the exception of a few, small private inholdings.
Transportation to the BCEW is primarily by automobile, but vans and buses
can be used to access the area. Driving time to Flagstaff is 1 hour and
about 1.5 hours to Phoenix. Major air transport to the vicinity is through
Phoenix, AZ, and a commuter airline serves Flagstaff.
Munds Park, the nearest village, has a population of about 3,000 to 6,000
(depending on season), and is about 32 km (20 mi) from the center of the
BCEW. Camp Verde (population of about 8,500) is 48 km (30 mi) from the
center of the watershed. Both Munds Park and Camp Verde offer complete
services for travelers.
The BCEW is characteristic of much of the Coconino National Forest along
the Mogollon Rim. The watershed includes plateaus, sloping mesas and breaks,
and steep canyons.
Bedrock underlying the area consists of igneous rocks of volcanic
origin, below these are sedimentary rocks of Kaibab, Coconino, and Supai
formations.
Elevations range from 900 to 2,400 m (3,000 to 8,000 ft) above sea
level.
Vegetation ranges from semi-desert shrub at the lower elevations,
to pinyon-juniper woodland from 1,500 to 1,800 m (5,000 to 6,000 ft),
and then ponderosa pine above 2,000 m (6,500 ft).
Precipitation and streamflow vary greatly from year to year. Seasonally,
flow is concentrated in a few months of each year when the snow melts.
The BCEW is a biosphere reserve,
a component of a worldwide network in Unesco's Man and the Biosphere
(MAB) Program.