The Tucson City Council is considering the implementation of an ordinance that would enact conservation rules on large water users and projects to protect the City’s water supply from thirsty developments.
If implemented, the proposal would require new businesses using 7.48 million gallons of water a month to submit water conservation plans. Conservation plans would need to demonstrate how businesses plan to reduce water use, water losses and waste.
The quantity of water adds up to roughly 90 million gallons annually. The threshold is set at the amount of water that would be used to serve 1,100 homes for a year.
New water users planning to use large quantities must use specified percentages of reclaimed water, which generally is at least 30%. The percentage of reclaimed water use will be heavily impacted by the proximity to reclaimed water delivery lines.
Council members claimed the ordinance is not intended to target specific businesses. The ordinance comes after Council voted to halt negotiations for the Project Blue data center campus. The project would have consisted of two large data center complexes that would have used roughly 6% of Tucson’s reclaimed water supply and 1% of the City’s total supply.
The development would have used drinkable water for the first two years and would then have pivoted to reclaimed water after the owner funded an 18-mile pipeline to deliver reclaimed water.
Officials have also said there are currently no businesses in Tucson that would be affected by the ordinance. Existing customers would be subject to new regulations if they seek to expand their water use beyond the threshold.
City officials said they want to implement regulations swiftly to make sure Council is prepared to handle proposed developments requesting to use large quantities of water.
The proposed ordinance is modeled after a similar ordinance approved by the Phoenix City Council in March 2024. Phoenix’s ordinance requires businesses to submit water conservation plans. This ordinance affects businesses using 250,000 gallons of water a month. Businesses using more than 500,000 gallons a month must obtain 30% of their supply from reclaimed water.
Conservation plans will be public record, including expected annual water use and peak daily water demand.
Certain groups, such as the Watershed Management Group, have said they want stricter regulations than are being proposed. For example, the group wants to extend protections on riparian areas and the aquifer.
City officials said they are interested in pursuing stricter regulations but want to swiftly move forward with the currently proposed ordinance. Council is expected to vote during its Tuesday meeting.
Potential Chip Factory
Garry Brav with BFL Construction has discussed bringing a chipmaking factory to the area. According to the Arizona Daily Star, Brav has held discussions with the City of Tucson, Pima County and state officials.
BFL Construction is currently developing the 110-acre PRINCE 10 project between Interstate 10 and the Santa Cruz River. The plan includes 12 development areas that have the potential to accommodate high-tech industry and office locations.
Chip factories differ from data centers in that they create more jobs but use more water. High volumes of water are used to rinse residue on silicon chips during the fabrication process. Chip factories are estimated to use anywhere from five-to-10 million gallons of water daily. This would result in water use that is nearly three times greater than the Project Blue data centers.
Chipmakers have continued to improve conservation practices. For example, Taiwan Semiconductor Manufacturing Company has indicated it wants to reuse 65% of its water. (Source)