The following is the opinion and analysis of the writer:

By Mark Johnson

Special to the Arizona Daily Star (July 14, 2022)

Mark Johnson is a retiredΒ water utility manager who worked in top management positions for three of the nation’s largest water utilities. He has been a community volunteer his entire life. He is a candidate for Marana Town Council.

Ensuring an adequate water supply is one of my major campaign platform items as a candidate for Marana Town Council. I have provided true, fact-based data and analysis of the current water situation, all supported by my 40-year career in the water utility industry.

Let’s clear the muddied waters with the following water truths.

Water supply in Arizona is managed on a regional and local level. The Tucson Active Management Area (TAMA) is our regional water system and includes the Avra Valley Aquifer and the Upper Santa Cruz Aquifer. Tucson Water, Marana Water and others manage their local water systems within TAMA.

At the regional level, TAMA’s goal is to achieve regional safe-yield, i.e., water out (pumping) is balanced by water in (natural and artificial recharge/replenishment). Any imbalance is overdraft.

From 1985 through 2020, TAMA has a cumulative overdraft of 1.8 million acre-feet. This means that over this 35-year period, 1.8 million acre-feet more water has been pumped from the aquifer than replenished. This fact is rarely discussed.

In recent years, TAMA has achieved annual safe-yield by replenishing the aquifers with Colorado River Water via the Central Arizona Project (CAP). However, considering the perilous situation with the Colorado River system, the Arizona Department of Water Resources predicts that TAMA safe yield as it stands β€œmay be unlikely” with further Colorado River shortages.

Regional groundwater quality is also a big concern, as portions of the aquifer are contaminated with PFAS compounds and the U.S. Environmental Protection Agency recently lowered the health advisory level to essentially zero for these chemicals in drinking water.

Although the regional water supply situation has improved in recent years, the future is not rosy with Colorado River water shortages, groundwater contamination issues and there is still the 1.8 million acre-feet deficit from past over pumping.

At the local level, Marana residents get water service from Marana Water or Tucson Water.

The incumbents tout that groundwater levels in Marana Water wells have risen and therefore all is good. But that is misleading because these wells are located adjacent to the replenishment facilities that are percolating Colorado River water into the aquifer! There are other wells farther away from these sites where water levels have dropped. They are not telling the whole story.

Furthermore, groundwater level has nothing to do with how much groundwater can be withdrawn. Marana Water will soon reach the point where its current approved 100-year water supply annual CAP allocation and recycled wastewater will be used up to meet rising water demand and then groundwater must be used. However, Marana only has a one-time groundwater allowance of about 3,000 acre-feet (one year of water). When that’s gone, any groundwater removed must be replenished with Central Arizona Groundwater Replenishment District water which is costly, shorter-term (not 100 years) and can be subject to the same cut backs as CAP water. The incumbents simply state there is plenty of groundwater and leave out the important details.

According to public records request data provided to me by Marana, the Marana Planning Commission and Town Council have approved 28,850 building lots as of the end of 2021. Marana has enough existing approved 100-year supply to provide water to 11,620 of those lots. Therefore, there are 17,230 lots of which there is not an approved 100-year water supply. The majority of the approved lots were the result of rezoning, whereby housing density was increased by a factor as high as 18. Rezoning and approving subdivisions prior to obtaining an approved 100-year water supply is not a sustainable action. It is reckless.

When I am elected to the Marana Town Council, I will work toward: 1) eliminating the TAMA cumulative overdraft, 2) monitoring aquifer groundwater quality and ensuring compliance with drinking water standards, 3) establishing a bona fide 100-year water supply before any rezoning and subdivision approvals, 4) ensuring Marana’s 100-year water supply takes into account that CAP water is not 100% reliable and 5) any groundwater replenishment water must be from a 100-year water supply source.

Rest assured; I will provide clear water facts.

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Mark Johnson is a retired water utility manager who worked in top management positions for three of the nation’s largest water utilities. He has been a community volunteer his entire life. He is a candidate for Marana Town Council.