Case Study: Santa Ynez Valley Union High School achieves precise sea-cliff erosion mapping for improved public safety with Trimble GeoXT

Mapping Sea Cliff Erosion in California Mapping Sea Cliff Erosion in California

Santa Ynez High School’s EAST program led the 2004–2005 Sea Cliff Erosion Mapping Project in response to severe erosion at Isla Vista’s oceanfront cliffs—an area with a seasonal population of 22,000 where 40–60-foot cliff failures had led to building condemnations, lawsuits and an average of five serious fall injuries per year. County environmental geologists needed spatially accurate, up-to-date data to improve public safety, land-use decisions and planning.

EAST students used Trimble GeoXT GPS units, ESRI ArcMap GIS, aerial imagery and field photography to map the cliff edge and base, differentially correct field data, and produce an informational DVD and detailed map layers for county and university review. Their analysis estimated an average erosion rate of 0.98 ft/year, projected historical and future cliff positions (1975–2055), and delivered actionable data to Santa Barbara County and UCSB to support further studies, public meetings and safety planning.

Santa Ynez Valley Union High School