Thursday, March 1, 2007

Future Droughts Will Put Pressure on Ground Water



The National Resource Report on “Colorado River Basin Water Management” issued last week got national attention.

The study used tree ring data to reconstruct river flows and drought records back hundreds of years and “transformed the paradigm on the history of river flows.”

The report concluded that “the preponderance of scientific evidence suggests that warmer future temperatures will reduce future Colorado River streamflow and water supplies. The paleoclimate record shows periods when Colorado River flows were lower than the gauged record assumed in the 1922 Colorado River Compact allocations.”

It also stated that, “tree rings and other data suggest future droughts will recur and may exceed the severity of historical droughts.”

So, we have over-estimated the amount of Colorado River water we should expect long term, and under-estimated the severity of droughts. This is going to put more pressure on the state’s ground water supplies which are already being rapidly mined. It also will lead to more subsidence and earth fissures.

The full report can be viewed, downloaded, or purchased at http://books.nap.edu/catalog.php?record_id=11857