Global Environmental Assessment Project - Belfer Center for ...

(Gunderson, Holling, and Light, 1995). In the Columbia Basin, for example, management approaches
that take into account recent scientific advances are now being considered. There is a movement away
from command-and-control strategies to one that acknowledges uncertainty in oceanic survival and
advocates the application of ecological principles. The most noticeable example of this shift is the
serious discussion of dam breaching on the Lower Snake River.
In the Colorado Basin, historic and tree ring-based flow data indicate water supplies are over-allocated,
but basin states have grown to expect minimum amounts of water, and exert political pressure to ensure
these allocations continue or improve with time. Since severe drought has not yet impacted the
Colorado Basin in its modem structural and institutional state, water managers have little incentive to
re-evaluate current interstate water policies. Recent intra-state water marketing and transfers in
California and discussion of interstate banking in the Lower Basin indicate this is changing, but it is
unclear how advances in water allocation flexibility will improve the basin-wide response in a severe,
sustained drought. For the time being, it appears that constraints imposed on interstate water
management by the Law of the River, and the long history of competition over scarce Colorado River
water, prevent the adoption of the institutional recommendations advocated by the SSD assessment. A
somewhat more open and adaptive management system in the Columbia Basin, led by the Northwest
Power Planning Council and the PNW Regional Assessment, seems to facilitate the consideration of
progressive management approaches.
Independent of political and legal circumstances that inhibit or promote the use of abrupt climate
change information, structural and climatic factors may lead to more frequent crises in the Pacific
Northwest. In the Columbia River Basin, the effects of poor oceanic conditions are exacerbated by the
phalanx of dams that salmon encounter in their migration to and from the ocean. In the Colorado Basin,
on the other hand, the construction of Hoover and Glen Canyon Dams dramatically increased basin
states buffer against multi-year drought. 19 During the 1987-92 drought event, for example, no major
restrictions were placed on the basic allocations outlined in the Law of the River, despite the fact that
reservoirs were at their lowest levels in the last 30 years. 20 Thus, dams serve to facilitate water resource
management in the Colorado Basin, mitigating the impacts of water shortage, while frustrating salmon
management in the Columbia Basin, by contributing to habitat degradation. The result appears to be a
greater likelihood for crisis, and hence weighing of alternative policy options, in the Pacific Northwest.
Climatically, salmon management in the Columbia Basin is more likely to experience crisis events - at
least with respect to the Pacific Decadal Oscillation, which changes phase roughly every 20 years. Not
only is their historical experience from previous phase shifts, but there is also the imminent threat of
similar changes occurring in the near future. In the case of the Colorado Basin, a drought like that
outlined by the SSD study has no adequate historical analog, and thus there is no institutional memory
of the magnitude or impacts of such an event. Furthermore, the apparent low probability of the SSD
scenario could invite resource managers to write off the possibility of it occurring while they're in a
policy or management position.
RELEVANCE TO GEA CONCEPTUAL FRAMEWORK
The research framework of the Global Environmental Assessment project identifies three qualities of
assessments that have been useful in previous empirical studies (Clark, 1999). They include saliency,
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