These are my conclusions—subject to correction, input and revamping. I truly invite others’ comments, suggestions, insights and conclusions, so that we can have an on-going dialogue--Nancy
1) Ken Seasholes (Department of Water Resources) and Eric Holler (Bureau of Reclamation) both emphasized again and again that CAP water is only one piece of the solution—we need several methods in place. 5,000 af of water will not offset the average 59,000 af of usage in the area. So the issue of bring CAP here is only a small part of the solution.
2) As I have always maintained it is an expensive venture to bring CAP to GV for 5-6% of the usage. So it’s clear to me that CAP water would have to be treated and piped directly to the two water companies that hold allocations. It would be foolish to recharge it into the groundwater where it would be pumped out by FICO and Phelps Dodge. Although this strategy will provide water to the residents, it does not deal with the subsidence issue/water deficit issue. However, the 5,000 af of available CAP allocations would not really effectively deal with it either.
3) That said, could there be a possibility of a retention basin, judiciously placed in an area that would not receive drawdown from agriculture or mining, which could receive additional CAP water [not from our allocations, but a way to get additional water for storage] from Arizona Water Banking Authority? Since we are in an upstream location, it might be advantageous. Also, so it could recreate a mound/barrier to hold back the PD sulfate plume moving into the new well fields.
4) There are areas that have good conditions for storm water infiltration (ie. no layers of clay), but they must be selected carefully to be placed in settled areas with little sediment movement and grass-lined as in the successful Chandler model. Also, it would be advantageous that they were placed near existing water wells, so that there could be a measure of their effectiveness. If the HOA’s are given the choice: do you want to put in dry wells or have subsidence in the future? I think they would wake up. The residents have not been given the true picture of water situation, so how can they respond effectively?
5) Since municipal use is only 6%, conservation, while always necessary, will have negligible results.
6) The Pima County Wastewater treatment plant produces 2,100 feet of effluent. Tom Berry said ninety per cent of it goes to Quail Creek for landscape, etc. [I’m checking on that number.] Is this the best use of effluent? Note: Someone finally told me the whole story, which has been avoided by every public wastewater person. Quail Creek builders entered into an agreement with the county to pay for the renovation needed at the wastewater plant (it was out of compliance) in exchange for all of the wastewater. Do they actually use the wastewater. No. They pump groundwater and get "credits" for the amount of wastewater recharged to the aquifer.
Again, the usage figures:
FICO 24,000 – 27,000 acre feet
So rounding off and factoring in some growth:
A total “out” that averages 59,000 acre feet
The recharge figures:
Natural storm water 19,000 acre feet
A total “in” of 28,000 acre feetThis gives us a deficit of 31,000 acre feet