Hydrologically sensitive areas, land use controls, and protection of healthy watersheds

Land use changes driven by urban development impose immediate threats to watershed health and sustainability of water resources. Municipalities can implement various land use controls to direct future urban development that has long lasting impacts on water resources. Hydrologically sensitive areas (HSAs) are the areas in landscapes that most actively contribute to runoff generation. This study establishes the connection between land use controls at a municipal level and protection of healthy watersheds through the concept of HSAs and assesses the effectiveness of five land use controls in protecting HSAs from future urban development in three selected municipalities in New Jersey. The five land use controls are steep slope ordinance, stream corridor ordinance, open space and farmland preservation, and wetlands protection. The results indicate the five land use controls protect 44-64% of municipal HSAs, which are only about 22-26% of the total area protected from urban development by those land use controls. The stream corridor ordinance is the most areally extensive, but wetlands protection is the most effective land use control in protecting HSAs in the three municipalities. These land use controls have significant potential to protect HSAs if additional protection criteria are incorporated into their implementation. The assessment provides practical guidance to land use planners and water resource managers who manage landscapes for water resource protection and environmental quality improvement.