Impacts of land covers on stormwater runoff and urban development: A land use and parcel based regression approach

Extensive studies have shown that stormwater yield and quality in a city are heavily influenced by its land uses and land covers (LULC). However, the majority of these studies have been done at the major watershed levels using remote sensing data with only a few urban LULC types and at lower resolutions. This empirical study uses the City of Corvallis, Oregon in the U.S. as a case to establish robust regression relations between existing urban LULC and stormwater yield or quality at the land parcel level by environmental models and high-resolution spatial data. The environmental models are based on parcel-level hydrological conditions and spatial analysis to assess the watersheds and land parcels suitable for minimal stormwater yield and highest quality for single and mixed-use urban development scenarios containing buildings, roads & driveways, sidewalks & paths, parking lots and open spaces. This study not only can provide a novel approach for local jurisdictions to evaluate the impacts of public urban development plans on a built environment but can assist private property owners to estimate the impacts of their private development projects. In addition to analysing hydrological conditions and conducting green infrastructure design upon the completed urban land use plan in previous studies, the present work indicates the necessity and possibility to apply parcel-level hydrological spatial analysis to assist local land use planners and watershed managers in making informed decisions with regard to land development scenarios at the initial stage.