The Coon Creek Water Yield Augmentation Project: implementation of timber harvesting technology to increase streamflow

The Goon Creek pilot project represents an attempt to verify that water yie ld augmentation technology, demonstrated to work on small-scale experimenta l watersheds, could be applied at an operational or large watershed scale w ith similar results. Goon Creek, a 1673 ha catchment on the Upper East Fork of the Encampment River, was selected as the treatment watershed and Upper East Fork, an adjacent catchment, was selected as the control. Following a n 8-year calibration period, road building and timber harvest occurred on 2 3.7% of the watershed area. Seasonal streamflow (April-October) significant ly increased on an average 76 mm for the first 5 years after harvest. Annua l peak flows, expressed as either the instantaneous maximum flow or as the maximum mean daily flow, were not significantly increased although the freq uency of occurrence or duration of days of the higher, near bankful, discha rges were extended. The findings at Goon Creek support and are comparable w ith documented observations on smaller experimental watershed studies in th e cold snow zone. (C) 2001 Elsevier Science B.V. All rights reserved.