Using Western Landscapes - Mountains and Plains: The Ecology of Wyoming Landscapes - page 307

Fig. 18.2. cultivated land, usually restricted to lowlands
where water is accessible, provides open space as well. the im-
pact on the native flora and fauna is significant, but the land
still provides habitat for some kinds of wildlife, and many

people appreciate pastoral vistas, such as this one. in the new
West, land trusts work with property owners interested in
conserving the habitat and ecosystem services provided by
such places.

of ecosystem management and ecosystem services, and
adaptation to climate change.

onto the land, but only at great cost. new reservoirs and
trans-basin diversions are on the planning boards, and
existing diversions are being upgraded. State laws and reg-
ulations have placed constraints on such developments—
reflecting the view of many that the few unregulated
rivers that remain are a valuable resource. Also, though
still difficult to implement, state laws now recognize
instream flows as a beneficial use of water, and portions
of some rivers are now protected under the Wild and Sce-
nic Rivers Act of 1968. in Wyoming, the protected rivers
are the headwaters of the Snake River and the clark's Fork
of the Yellowstone River. combined, they represent less
than 0.4 percent of the state's river miles. 5
Groundwater is another issue. the ogallala (High
Plains) aquifer on the western Great Plains, extending
from nebraska and eastern Wyoming into new Mex-
ico and texas, has supplied agriculture and munici-
palities for many years, but the rate of withdrawal
exceeds the rate of recharge. Significant drawdowns
of this aquifer have forced some farmers to revert to
dryland farming. 6 Furthermore, groundwater in some
areas has been degraded through the deep percolation
of polluted surface water. clearly, humans have the
capacity to affect deep groundwater supplies. Recent

Water Development

not surprisingly, water is a limiting factor for human
activities throughout the region. the traditional solu-
tions have been to construct reservoirs, irrigation sys-
tems, and trans-basin diversions, thereby making water
available wherever economically feasible and politically
desirable (fig. 18.3). Faced with interstate competition
for water and the rights associated with prior use, a
common attitude has been to “use it or lose it.” Pro-
moted historically by the U.S. Army corps of engineers,
the U.S. Bureau of Reclamation, and local chambers of
commerce, and heavily subsidized by state and federal
grants and loans, such projects have indeed stimulated
the economy. Also, the projects have often created
additional benefits, such as flood control, hydroelectric
power, and new recreational opportunities.
Still, regulated rivers have replaced rivers that flowed
freely long enough to cut canyons through mountain
ranges, and many reservoirs will probably be silt laden
in less than a century. Reservoir silt can be pumped back