Recently, water officials in Tucson announced that well readings indicated that the level of the aquifer was staying stable, a major accomplishment.Their outlook is that the Colorado River will only decrease a small percentage in the coming years and even if the worst case scenario came to be that the CAP stopped flowing, they claim that Tucson has a 50 year supply of water in its aquifer. For the past 20 years or so this source of the Colorado River has been the primary water source supplying the city, allowing the natural water cycle to replenish the aquifer. To combat losing the aquifer altogether, as well as fight the subsequent subsidence that was crippling buildings, walls and roads in town, the CAP or Central Arizona Project canal was constructed from Lake Havsu City 336 miles across the desert to Tucson. As the population grew, the level of the aquifer dropped significantly (from 35 feet in 1900 to 300 feet today). Tucson has a huge aquifer under the city which was the prime source of water for much of the city's history. Simply by changing the options at the store there has been a dramatic reduction in the amount of water that residents use.However, several variables are not accounted for in the graphs publically available, some of them admittedly so. Due to regulations on product manufacturing, showerheads, faucet aerators and toilets are now made to use much less water than they used to. Their data show a stable supply with leveling demand despite growing population.
Water officials in Tucson are quick to point out that Tucson is very well positioned for its future water needs. I am neither a hydrologist nor an expert on Tucson's water but it is of interest to me so I follow it when I can.