Fig. 1

(a) Visualization of IB’s stormdrain system along with the eight watersheds used for residency identification in the social survey, and the monitoring site location used for hydrologic validation, (b) Location of Imperial Beach (red circle) in California (grey outline) along the border of the United States and Mexico (black outline). Created using ArcGIS Pro version 3.2.2, https://www.esri.com/en-us/arcgis/products/arcgis-pro/resources.