The Application of WEPP to Natural Gas Exploration and Production Sites

Abstract

Natural gas development in the United States has been increasing in recent years, with over 30,000 new sites added per year. Natural gas exploration and production (NGE&P) sites disturb several acres of land, increasing the potential for accelerated soil losses due to land cover modifications, increased slopes, and flow concentration. The contribution of sediment from multiple NGE&P sites in a watershed may potentially warrant inclusion in a sediment TMDL source assessment. Models are often used to assist in source assessments. WEPP was chosen to model sediment yields from NGE&P sites because both the spatial (field scale) and temporal (single storm event) scales were applicable and because WEPP was specifically developed for a variety of different land use/land cover conditions including disturbed sites. This research project was designed to evaluate the ability of WEPP to adequately predict sediment yields from NGE&P sites in north central Texas. Sediment yields were measured for a total of fifteen storm events at three sites and compared to WEPP modeled sediment yields using the Nash-Sutcliffe model efficiency coefficient. Data from three storm events were used to calibrate the model, and data from the remaining twelve events were used for model validation. The model produced a validation efficiency coefficient of 0.71. Results of this research demonstrate that WEPP is effective for field scale modeling of sediment yields from NGE&P sites and that WEPP could be used to develop sediment TMDLs under these land use conditions.