Friends of the Santa Cruz River advocates for the protection of southeastern Arizona’s Santa Cruz River, considered one of America’s most endangered rivers. Stretching 180 miles from the San Rafael Valley south into Mexico and then north toward Phoenix, the river is a migratory bird corridor home to mesquite bosques and cottonwood willow forests, even as the river itself is only inches deep most of the year. Although the river improved with the upgrade of the Nogales International Wastewater Treatment Plant in 2009, it remains under threat due to climate change and groundwater declines, which will only worsen when a new mining company, owned by South32, is fully in operation, pumping 6.5 million gallons of groundwater per day from the Patagonia Mountains. Even though South32 has promised a state-of-the-art treatment plant, FOSCR board president Ben Lomeli says that “even the most modern facilities can fail and we want safeguards and monitoring to detect any contamination issues.”
The organization works with private landowners, water companies, government agencies, researchers and environmental advocacy groups in both the United States and Mexico to monitor the flow and quality of the Santa Cruz River, advocate for the protection of the region, and host education and outreach programs. It regularly partners with groups for trash cleanup days, covering not only the river but the surrounding tributaries and roads. “If it’s in the streets, it ends up in the river,” said Lomeli. Before the pandemic, the organization hosted annual community picnics and partnered with local schools for the “Celebrate the River” student art contest, which has displayed winning art in nearby galleries and county offices. Recognized in 2025 by the Arizona Department of Environmental Quality for its excellent stewardship, Friends of the Santa Cruz River is an all-volunteer organization with nine board members and is currently seeking funding to improve its web and social media presence.
Chavez Siding Crossing, looking upstream. Photo: Ben Lomeli