The effect of the Forest Legacy Program on water quality

Abstract

Nonpoint source pollution is the leading cause of water quality impairment in the United States, with forest management activities contributing to this diffuse pollution. The Forest Legacy Program aims to conserve working forests while mandating adherence to forestry BMP. This thesis evaluates the impact of the Forest Legacy Program on water quality, marking the first comprehensive assessment of the program's ecological impact. To create a national dataset, I aggregate monitor-level water testing results, Forest Legacy Program tracts, and 4 km-grid average temperature and precipitation data to the month by Hydrologic Unit Code 08-digit level from January 1990 to February 2024. Results suggest that enrollment into the Forest Legacy Program may influence landowner land management practices towards BMP that reduce water pollution from sediment and nutrient loads. However, unaddressed selection bias caution interpreting as a treatment effect. These findings underscore the complexities of evaluating conservation programs and highlight the need for further research to assess causal mechanisms and address limitations.