A generation from now a $4.1B desalination plant in Sonora could help alleviate worst-case-scenario water woes in Pima County.
A Pima County Regional Wastewater Reclamation Department study examined possible water sources if Central Arizona Project‘s Colorado River water supplies dry up and the county population grows to 1.5 million by 2100.
One possible solution is a desalination plant that is proposed to convert saltwater from the Sea of Cortez and then move it nearly 200 miles by pipeline to Pima County.
Officials place the project as roughly equivalent in scale to the creation of CAP, which cost $4B in 1993 dollars. The CAP authorization process started in 1968, and its development took nearly 40 years to complete. Officials estimate the desalination and pipeline project could take 20-40 years for approval and financing and construction could cost Tucson-area homeowners up to $60-$90 a month in new water bill charges. The study assumes the federal government would pay for half the project costs.
Because of issues involved with disposing of brine waste in the desalination process, the technology is generally opposed by environmentalists and conservationists. Opponents also cite the heavy costs borne by economically disadvantaged residents.
Officials stress, however, that now is the time to begin considering contingencies for the future.
Current forecasts predict ongoing and worsening shortages in CAP’s available water supply, and multiple studies and proposals are in various stages of development and discussion to address the issue. (Source)