Urban watershed management: Using remote sensing to implement Low Impact Development

This paper discusses how remote sensing, specifically Light Detection and Ranging (LiDAR), was used to carry out a detailed Low Impact Development (LID) suitability estimate in an urban watershed. The research uses LiDAR as an accurate and efficient tool for identifying and quantifying LID retrofit locations. The results of the LiDAR analysis were run in a hydrologic model to determine the flood response to various LID implementation scenarios. The overall goal of the research project is to determine whether LID can effectively mitigate the flooding that is predicted to occur due to climate change. LID relies on runoff management measures that seek to control rainwater volume at the source by retaining and infiltrating rainwater. Multiple datasets derived from LiDAR were used to identity suitable LID retrofit locations in the Bowker Creek watershed in Victoria, BC, Canada. LiDAR-derived drainage vectors, Digital Elevation Models (DEM), and Digital Surface Models (DSM) were used in combination with existing GIS data in a selection process that strategically located facilities in areas that optimally reduced peak flow rates and met municipal criteria.