HYDROGEOLOGY OF A SUSTAINABLE LARGE-SCALE FOREST RESTORATION TREATMENT IN ARIZONA

Almost 800,000 acres (30 %) of the 2.4 million acres of the ponderosa pine (Pinus ponderosa) forests of the Kaibab, Coconino, Apache-Sitgreaves and Tonto National Forests of Arizona are being identified for a landscape-scale treatment to improve forest health with an associated sustainable timber industry. This proposed action is part of the greater Four Forest Restoration Initiative (4-FRI) and Statewide Strategy for Restoring Arizona’s Forests. In the arid and semi-arid Western U.S., these upland forests play an important role in the health and sustainability of watersheds. They provide not only an important resource for their woody forest products, but for the role they play in managing recharge to deep (over 1,000 feet deep) regional aquifers. Forest restoration efforts produce woody biomass that can be used by a sustainable appropriately-based wood products industry, which in turn helps create jobs and achieve economic sustainability. Foresters, scientists, environmentalists and private industry leaders have joined together in the 4-FRI. Together they are committed to restoring forests that will become assets, not liabilities, to future generations. Hence, it is important that any management changes to these forests, including large-scale restoration, is informed by the affects these management changes will have to watersheds. A recently completed regional groundwater flow model has been evaluated in parallel with the limited hydrogeological monitoring stations to develop methods to assess the impacts of the proposed restoration treatments on the regional aquifers and their associated springs and baseflow supported streams.