The purpose of this project was to assess the Association of Monterey Bay Area Governments (AMBAG) Light Detection and Ranging (LiDAR) and bare earth Digital Elevation Model (DEM) datasets and conduct stormwater flow analyses. City officials would like to know if the AMBAG LiDAR and associated DEM accurately represent the relatively flat topography of northeastern Salinas, an area that lies in the floodplain of the Salinas River and is prone to flooding. We utilized a geodetic dual-frequency GPS to obtain static occupation checkpoints at various locations to test vertical accuracy of the cleaned LiDAR and DEM. In addition, we compared the costly LiDAR derived DEM to publicly available datasets. We also produced contour lines, delineated local watersheds, and conducted water flow analyses, incorporating current infrastructure (storm drains and other outfalls). We found vertical accuracy of the LiDAR points to be within 0.43 ft in open, non-vegetated areas, and within 1.53 ft in vegetated areas under canopy. Comparison of the AMBAG DEMs to publically available data revealed that the datasets were very similar. Our flow models resulted in 14 subwatersheds and indicated that water in the study area flows into Natividad and Gabilan Creeks via streets, open channels, and drainage systems. We recommend that the City of Salinas (1) explore publicly available elevation datasets before investing in costly LiDAR surveys in the future, (2) assess stormwater infrastructure in the study area to help reduce flood risk, and (3) comprehensively map outfalls and re-execute the flow analyses carried out during this project.
Read the final student report delivered to the local gov/community partner.
Sustainable City Years Program Contact Info
University Faculty Contact
Rikk Kvitek
Natural Sciences
Professor
rkvitek@csumb.edu
Local Government / Community Contact
Eric Sandoval
GIS