Gleick comments on USGS water usage numbers and quality connection

Yesterday morning, NPR's Morning Edition program ran the story Water Use Is Lower Than It Was 30 Years Ago. The story was an interview with Peter Gleick of the Pacific Institute and his take on the most recent per capita water use numbers by the USGS.

The interview follows the release of the long-awaited updated usage numbers from USGS in Estimated Use of Water in the United States in 2005.

As always, Gleick makes several interesting points. In a straightforward review of the USGS numbers, the story points out that per capita water use has dropped approximately 30 percent since 1975. Gleick breaks that number down to show that industrial and irrigation uses are declining, while water used for power plants and for residential usage shows small increases.

This last fact he ties to our region by pointing out that as Americans move to the hotter, drier southwest and attempt to import our same gardens and lawns, we see an increase in per capita water usage.

One point of particular interest to water quality geeks that may not usually track water use numbers is Gleick's connection of the decreasing trend in industrial and irrigation uses to stronger wastewater discharge limitations (as well as to scarcity). Gleick says that as requirements for reducing pollution in wastewater discharges tightened, industry got more efficient:

"…one of the cheapest and smartest ways to deal with wastewater is not to produce it in the first place."

So a quality concern is driving a quantity issue (efficiency of use/conservation), but this may be a double-edged sword for some rivers in the West. As many of you are aware some of our rivers are dubbed "effluent-dependent" or "effluent-dominated", meaning their flows are made up – in whole or in significant part – by wastewater effluent. Removing or reducing wastewater discharges in those rivers may substantially (or in an extreme case entirely) reduce river flows.

This begs the question of where conserved water goes, and what that means for the larger health of our rivers. This is a debate that will only grow hotter as the intersections between quality and quantity of water increase, particularly in our semi-arid region.

You may also be interested in Bevan's take on the water-energy connection in these numbers in our Saving Water, Saving Energy blog.