1. PFAS in Rio Rico and South Tubac. People are concerned about the exceptionally high levels of PFAS in the drinking water in this area (as reported by USA Today). The questions we get most often are:
A) How do we protect ourselves and our families?
B) What, if anything, can/will be done to combat this problem?
C) Is the EPA or ADEQ taking any action to mitigate this issue?
D) What responsibility does Liberty water have?
Response: Earlier this year in April, EPA issued the first-ever national, legally enforceable drinking water standard to protect communities from exposure to harmful PFAS. As part of this rule, all regulated public water systems in Arizona, including Liberty Water, have three years to complete initial monitoring for these chemicals, which requires several samples to be collected and analyzed over a period of time. Systems must include their results in their Annual Water Quality reports to customers and systems that detect PFAS above the new standards, like Liberty Water, will have until April 2029 to implement solutions that reduce PFAS in their drinking water.
ADEQ has developed technical guidance documents for Arizona drinking water systems and engineers that are evaluating options for reducing PFAS in drinking water. ADEQ will continue to provide technical assistance to systems, though it is ultimately the systems’ responsibility to ensure that they meet the new standards by 2029.
In addition to implementing the federal drinking water regulations, EPA and the state are taking additional actions to address PFAS in drinking water. Both Arizona, through partnership with our state universities, and EPA have invested in research and innovation to increase our understanding of PFAS and develop new technologies for treatment. Additionally, ADEQ recently gathered information on PFAS detections and local hydrogeology in several parts of the state impacted by PFAS, including the Santa Cruz River Basin, in an effort to better evaluate potential solutions.
EPA has many resources available for those concerned about PFAS in their water, including a factsheet on the new PFAS drinking water regulation. For anyone considering using or installing in-home water treatment, EPA has another factsheet with more information about the use of home water filters. The Arizona Department of Health Services (ADHS) also has information available on their website, including a useful PFAS infographic. ADHS can help answer health-related questions about PFAS; they can be contacted at 602-364-3118 or environmentalhealth@azdhs.gov.
2. Nogales Wash: There is a lot of concern from folks who live near the wash. The smell throughout the summer was excessive and the mosquito problem was much more than normal this year. People are concerned about mosquito-borne illnesses. And your favorite, tires and trash building up.
Response: We provide more information on mosquito’s in the response to question 4 below, but here are a few general updates on some of the waste issues we are working on along the border:
ADEQ participates in the binational cross-border sewage spills rapid response team, where there is a strong and effective communication with partners from both sides of the border. Through this binational group, cross border sewage spills that originate in Nogales, Sonora and enter the Nogales Wash/Santa Cruz River are usually addressed immediately, allowing authorities from both sides of the border to notify the public of the risks if coming in contact with the water while solving the situation.
In order to address the waste situation in the Nogales Wash and the Santa Cruz River, ADEQ has worked and continues working on several projects with our partners from Ambos Nogales to address the waste management issue that affects our waterways in the Arizona side (Nogales Wash and Santa Cruz River). Most of these projects have been developed under the umbrella of the US EPA Border Program (https://www.epa.gov/usmexicoborder/what-border-2025).
One of the most current efforts, which was worked in collaboration with the local authorities from Nogales, Sonora, consisted of identifying illegal dumpsites in the municipality, for their clean up. This effort included a reporting system through an app that allows the local government in Nogales, Sonora to track these sites and clean them up,which also has the effect of reducing waste transport across the border during flood events.
There have also been efforts focusing on waste tires disposal for this region. In fact, ADEQ is working with their counterpart in the State of Sonora, CEDES, on developing a binational waste/used tires management plan, to be implemented in the next couple of years through the Arizona-Sonora Commission. This Plan includes the development of a diagnostic of the existing waste tires along the Arizona-Sonora border region, and ways to better solve the environmental and public health impacts that these bring along.
Another effort aiming at addressing the waste management situation that pollutes our waterways in the Ambos Nogales area, was one that was sponsored by the company Constellation Brands in July, 2024, coordinated by the Sonoran Institute (Luke Cole), in collaboration with the City of Nogales, Santa Cruz County and ADEQ. This pilot project consisted in the installation of a litter trap in one of the streams (Ephrain Canyon) that arrive at the Nogales Wash, to trap and contain waste being transported through this water flow. The purpose of this project is to measure the effectiveness of these technologies to detain waste and other debris before reaching the Santa Cruz river, preventing its contamination and the effects of this in the ecosystem.
3) To whom can we direct people that need to make a complaint about a problem along the wash?
Response: If you are aware of a cross-border environmental situation originating in the Mexican side of the border that directly impacts the Nogales Wash, please contact our border liaison Claudia Gil, at gil.claudia@azdeq.gov. Also, you can always report issues that you or the community are seeing on the Arizona side to Aaron Tews, the liaison for the region (tews.aaron@azdeq.gov, 520.471.1486). Both teams will work with you to identify the proper channels of communication. Finally, you can also file a complaint online (https://legacy.azdeq.gov/function/compliance/complaint.html). You do not have to make a complaint against a specific facility to let us know about an issue.
4)Is there a way to control some of the mosquito activity?
Response: Although pest control, including mosquitos, is general outside of our jurisdiction, EPA has some useful resources online to help mitigate the mosquito issues:
Response:We do not currently have a non-profit group that we are working directly with on cleanup activities along the river. However, we have supported cleanup efforts in the past. I know that you have already met and are working with Meghan Smart, our Senior Community Science Coordinator on sampling in the Patagonia area. To set up a cleanup event or to facilitate further participation in volunteer efforts along the Santa Cruz River, I encourage you to reach out again to Meghan at:smart.meghan@azdeq.govor 602.771.4506.
