HYDROLOGIC RESPONSES OF A HIGH-ELEVEATION RHEOCRENE SPRING TO FOREST RESTORATION (Invited Presentation)

Over a century of grazing, fire exclusion, and road use have greatly impacted the function of a rare, high-elevation spring in Northern Arizona. The perennial rheocrene spring system, Hoxworth Springs, is a critical freshwater ecosystem. The spring ecosystem was significantly altered in the early 1900’s from activities associated with forest logging. It was restored by the Arizona Department of Water Resources, Northern Arizona University, and the United States Forest Services in the late 1990’s. A logging road was removed, water diversions were removed, cattle and elk exclosures were built, and modern forest thinning and fire management processes were implemented.

Humankind’s influence on Hoxworth Springs increased soil erosion and reduced water availability. To assess the response of the shallow karst aquifer supplying Hoxworth Springs from these restoration actions, an InSitu Level Troll 500 pressure transducer and one-inch Baski flume were used to collect discharge and estimate recharge rates. The hydrologic response of Hoxworth Springs was assessed using rating curves and hydrographs created from the discharge and recharge rates. It is anticipated that the flow of Hoxworth Springs will recover from the impacts of forest management based on forest restoration actions at other springs in the region. The recovery of the discharge at the spring will make the ecosystem more resilient to anticipated impacts from climate change.