Researcher ORCID Identifier

0009-0005-8906-9550

Graduation Year

2024

Date of Submission

4-2024

Document Type

Open Access Senior Thesis

Degree Name

Bachelor of Arts

Department

Environment, Economics, and Politics (EEP)

Reader 1

Warren Roberts

Reader 2

Branwen Williams

Terms of Use & License Information

Terms of Use for work posted in Scholarship@Claremont.

Rights Information

© 2024 Miller Alexander I McCraw

Abstract

The rising threat of coastal erosion to California’s beach ecosystems and economy has fueled a rise in coastal stabilization projects, including beach replenishment. This process’s potentially adverse impact on a beach’s topography and ecosystem makes post-replenishment monitoring essential for long-term coastline management. Drone-based monitoring presents itself as a faster, cheaper, and safer alternative to traditional post-replenishment monitoring but has little proof of concept as a practical substitute. This study used drone-based photogrammetry coupled with publicly available wave data to track elevation changes at Doheny and San Capistrano Beach after a beach replenishment project to both determine the beach’s resilience to normal and storm conditions and test the efficacy of drone-based monitoring. Elevation comparisons between eight surveys from October to February found the replenished area saw rates of erosion beyond two meters in regions with abnormal topography like berms and the center of the survey area, with lower rates of erosion and marginal rates of replenishment occurring in flatter and border regions. While errors were less than an inch for the initial drone photogrammetry, survey error rose during the point cloud alignment and multiscale model-to-model cloud comparison intended to detect elevation changes between surveys, revealing potential shortcomings in current topographic comparison softwares for drone-based post-replenishment monitoring.

Download

Share

COinS