A HISTORY AND EVALUATION OF WASHINGTON STATE'S FOREST PRACTICES RULES FOR UNSTABLE SLOPES
Washington State Forest Practices Rules were extensively revised in 1999 through the Forests & Fish Agreement. During the Forests & Fish Negotiations, a stakeholder team of unstable slopes experts and policy personnel distilled the results of the watershed analyses and proposed rules that identify and protect landform-based unstable slopes. The landform-based unstable slopes rules have been implemented on private and state timberlands since March, 2000. By 2002, a scientific advisory group working within the Adaptive Management Program had written a protocol called Landslide Hazard Zonation (LHZ) which more rigorously outlined data collection for the landslide inventory and detailed a process for delineating potentially unstable slopes and assigning a hazard rating. Landslide inventories and unstable slopes mapping for an additional 30 watersheds and 6 other blocks totaling 1,115,000 acres have been accomplished under the LHZ Protocol. The LHZ protocol provides a standardized and systematic database to help evaluate the validity of the rule-identified landforms. Other research to test the effectiveness of Washington State Forest Practices Rules is ongoing and includes a field-based inventory of landslides that evaluates different harvest and road treatments following the December 2-3, 2007, storm in southwest Washington.