Irrigated farming with desal

Water cliche alert.
The former mayor of Phoenix wants to see desalination plants lining the Sea of Cortez to supply future water needs in Northern Mexico and Southern Arizona because he says "water is going to become, if it’s not already, more valuable than gold or oil.”  Apparently the economy is humming along so nicely in Phoenix they believe they are going to be the next Saudi Arabia.  Why Saudi Arabia?  Because that is the only place I know of relying heavily on desalinated water for municipal and industrial (M&I) needs (it may have something to do with the cheap cost of power in that region).  If you're talking about using desal to supply irrigation water (which is where most of the water is used within areas that border the Sea of Cortez) you are in similarly sparse company.  Israel and Spain are about the only places currently using desalinated water for irrigation on anything resembling a large scale and much of that use involves treatment of brackish groundwater rather than seawater.  Those types of waters have a much lower dissolved mineral content than seawater, so production costs are also much lower, but it still isn't cheap water.

New "Green Streets" Policy on the way for Tucson

Image borrowed from HydroGeoWorks.com

Last week the Tucson City Council considered and approved a new policy that will direct the Transportation Dept. to implement passive water harvesting features on most future road projects within the city.  This policy was largely developed by Watershed Management Group (I'm biased as a former board member of WMG) who put in a lot of effort to build consensus and support for this sensible change in a desert city.  The policy calls for incorporating curb cuts and depressed basins adjacent to roads to collect, filter, and utilize storm runoff for fostering roadside vegetation that will provide shading (heat island reduction) and pollution mitigation (both air and water).  These are remarkably simple modifications that should save water, previously used for irrigation, in addition to reducing the strain on stormwater infrastructure.

Major kudos to the city and to WMG for making this happen.  And I should also mention James MacAdam, formerly with WMG but now working in the mayor's office, who I know was a major impetus in getting this done.

A Pretty Impressive Graph showing what Tucson Water has been doing with Renewable Water

At a recent meeting I attended at Tucson Water, their hydrology staff gave a presentation on where our water is coming from these days.  One graph in particular really drew a reaction from those in attendance: