Eastern Orthomosaic for Bywater-Reyes et al. (2026) Resilient St Vrain Assessment

Dataset associated with Bywater-Reyes et al., 2026, Lessons Learned from a Post Flood-Reconstruction Project of an Urban Stream (Resilient St. Vrain, Longmont, Colorado, USA), Geomorphology

Orthomosaic for the eastern section of the study area.

The study region was captured with drone imagery and overlapping images were post-processed for orthorectified aerial imagery and Structure from Motion (SfM) topography following best practices (Brodu & Lague, 2012; Westoby et al., 2012) using Agisoft Metashape. Additional in-channel topography and ground control were surveyed with RTK GPS. For SfM, ground control points (GCPs) were collected using a Trimble R10 unit with real-time corrections using their RTX service (EPSG:32613 coordinate system; WGS 84 / UTM zone 13N). Control point accuracy was within 1 cm horizontally and 5 cm vertically. Targets were a mix of black and white squares, 24in x 24in, as well as “X”’s created using strips of orange hazard tape. The aerial survey was performed on July 22, 2022 using a Matrice 100 UAV with a Rededge-M legacy 5-band sensor at 90 meters flight height with >80% overlap in imagery in both directions. Imagery was postprocessed with GCPs following the protocol outlined in (Bywater-Reyes & Pratt-Sitaula, 2022). Products included digital elevation models (DEMs) and multispectral orthomosaics.