Tucson and Marana have experienced significant increases in their water tables due to reduced groundwater pumping and the recharge of Central Arizona Project water from the Colorado River.
But Green Valley and Sahuarita have not been able to realize the same benefits of receiving and recharging CAP water because they are upstream from the closest recharge facility at Pima Mine Road. Some areas in the Santa Cruz Valley have suffered a serious decline in the aquifer - as much as 150 feet.
Two water utilities in the Green Valley area, Community Water Co. of Green Valley and the Green Valley Water District, have held CAP water entitlements for 4,758 acre-feet per year since 1984 (an acre-foot is roughly 326,000 gallons). However, there is no way for them to directly use their allocations until an extensive pipeline is constructed to access the CAP and bring the water nine miles south.
Now there are proposals for two pipelines, both of which offer hope and opportunity for the Sahuarita and Green Valley areas.
Why two pipelines?
The Farmers Investment Co. pipeline project will serve its pecan orchards that are permitted as a groundwater saving facility. The orchards demand 25,000 acre-feet of water per year, all of which is currently pumped from the local groundwater.
This project will enable CAP water to be used for irrigation of some of the company's pecan trees and will reduce the demand for groundwater. FICO can obtain about 3,900 acre-feet per year of CAP water. Importantly, FICO's groundwater savings facility is large enough to enable the offset of larger quantities of its groundwater pumping, by accepting CAP water that is available to others.
Project Renews is the Community Water pipeline project, and it extends farther south and is upstream of the FICO facility. Project Renews, funded by Augusta Resource (parent company of the proposed Rosemont Mine), has started installation of a pipeline and recharge basins that will accommodate Rosemont Copper's commitment to recharge 105 percent of its water use over the next 15-20 years.
Of even greater benefit to our local communities, the water providers and users in the Green Valley and Sahuarita area convinced Community Water and Rosemont of the merits of expanding their project to a 36-inch pipeline, with a capacity of 30,000 acre-feet per year. This will enable other users farther south to transport sufficient water to offset a major portion of our groundwater overpumping far into the future.
Project Renews already has CAP water available and is planning for water deliveries as early as 2015. FICO has indicated that it is ready to begin acquiring CAP water.
Both organizations face one hurdle: They have both requested connection to the CAP/Tucson Water pipeline that ends just east of the Santa Cruz River on Pima Mine Road.
There is enough capacity in the existing pipeline to allow both organizations to start receiving CAP water. However, permission is required from both CAP and the city of Tucson to connect. CAP has already indicated it will treat both projects equally and has approved the connection of both pipelines.
It is now up to the mayor and City Council of Tucson.
Both pipelines serve the community interest. Each organization with water rights has different needs and objectives. The two projects offer double opportunities for the residents of Green Valley and Sahuarita, and both projects benefit all of the metro area as we try and reach state-required water- conservation goals.
We urge the city of Tucson to follow CAP's lead and say "yes" to both pipeline connections now. It is the fair and right thing to do.
Ken Taylor is secretary and treasurer of the Upper Santa Cruz Providers & Users Group, and Virgil Davis is chairman of the Community Water Co. board of directors.