Geomorphic character of the Ash Meadows springs, channels, and wetlands-a guide to restoration (Ash Meadows National Wildlife Refuge)

Authors: Gourley, Chad*1, Mortenson, Susan1

Year: 2015 (xlvii)

Abstract

The Ash Meadows complex harbors many ecologically important wetland landscape features, many of which are composed of natural channel types. After assessing the geomorphic nature of the drainage systems, we determined that dissimilar size drainages and spring systems create geomorphically different channel systems and wetland features within Ash Meadows. After assessing the Ash Meadows National Wildlife Refuge to determine the: 1) undisturbed condition; 2) natural range of variability; 3) hydrological processes; 4) sediment sources; and 5) geomorphic characteristics, ecological designers developed plans for restoration. This presentation recounts elements of the biophysical assessment that directed ecological restoration design and reviews. The assessment showed that many of the spring heads and upper outflow channels have small catchment basins and a small volume of sediment contribution. These areas are low energy systems and are stable over time. Farther downstream the systems gains catchment area and become more dynamic. Restoration designs should take into account increasing stream power and potential for disturbance in the downstream reaches of the systems. The first restoration construction was completed in 1997 on Kings Spring, and the spring pool and outflow channel ecosystem began to recover. Almost two decades later, lessons learned from this project serve as a guide for current and future desert spring restorations.