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What Is the Impact of New Columbia River Water Rights?
Should “Mitigation” Policies for New Water Rights Be Based on Empirical Reality?
160
April - September Unregulated Runoff at the Dalles
(Linear Treadline Added, 1929-2013)
140
120
Volume (MAF)
In evaluating an issuance of new
Columbia River water rights, the
actual river system conditions—
and its relevance to cumulative,
water right net depletions over
time--are seldom taken into
account. This factor is illustrated
by the above depiction of longterm (unregulated) flows at the
Dalles for the 1929-2013 period.
Measured as a linear trend, there
has been an increase in observed
unregulated flows at The Dalles,
even though this is the period
that also reflects net water
depletions upstream from this
site, from irrigation, municipal,
and industrial water uses.
100
80
60
40
1929 1934 1939 1944 1949 1954 1959 1964 1969 1974 1979 1984 1989 1994 1999 2004 2009
Year
Based on technical verification
with staff from the Northwest
River Forecast Center, NOAA, and the Reservoir Control Center, USACE, it is determined that the
baseline (nominal observed) flows used at the The Dalles, to recalibrate to unregulated flows
(reservoir storage impacts), implicitly take into account net water system depletions above The Dalles
Project. Stated more concisely, there has been an observed net gain of about 7 million acre-ft. (MAF)
during a period of time when major withdrawal/depletions (about 13 MAF) occurred up-river within
the Columbia River Basin system.
Consequently, it is empirically unverifiable, at best, to make an assertion that current net water
depletions have had an adverse effect on flows/water volume within the mainstem Columbia River
system—as measures at a point like The Dalles. This reality begs an obvious question.
Should state policy makers and water resources managers reevaluate “mitigation” policies that
inhibit an issuance of new, Mainstem Columbia River water rights, or should policy reflect reality?