Cache County, Utah: drinking water report. Cache County in northern Utah has about 133,000 residents, including Logan and Utah State University.
Cache County in northern Utah has about 133,000 residents, including Logan and Utah State University. The county sits in the Cache Valley – a high-elevation basin surrounded by mountains – and draws water from mountain springs, wells, and the Logan River. Dairy farming and agriculture dominate the valley floor, while the mountains provide clean snowmelt that feeds the water supply.
The Cache Valley's temperature inversions trap air pollution during winter, but the water supply benefits from mountain source areas that are largely above agricultural activity. According to the Utah Division of Drinking Water's 2024 compliance data, all public water systems in Cache County met federal standards. The deep wells and mountain springs produce naturally clean water.
The Logan-Cache Airport has documented limited AFFF use. Utah DEQ's 2024 PFAS investigation found PFOS at 4 ppt in monitoring wells near the facility – at the detection limit. Agricultural nitrate from the valley floor dairy operations is present in the shallow aquifer but generally does not affect the deeper production wells.
Cache County benefits from mountain-sourced water that starts clean and stays relatively clean through the distribution system. Private well owners on the valley floor near dairy operations should test for nitrate, as the shallow aquifer is more exposed than the deep wells serving municipal systems.
Check your water for data at your address. For most Cache County residents, a carbon filter addresses taste and any residual chlorine. For well owners with nitrate concerns, reverse osmosis provides effective treatment. Our water filter guide covers both approaches. Pull your detailed report for local data, and visit our Utah page for statewide patterns.