Lytle Creek Historic Geomorphology
The Lytle Creek Project is located in San Bernardino County and is situated on the Lytle Creek Wash, a major drainage for the San Gabriel Mountains. The Lytle Creek project presented PACE with many unique challenges. First, in early 2005 a major storm event washed away an existing levee protecting a gravel pit located within the wash. In addition to the washed out levee there is a habitat preserve island in the middle of the wash protecting an endangered species, the Kangaroo Rat. PACE had to redesign an earthen filled levee to protect the gravel pit, levees on both sides of the wash to protect future development, and design these structures so no Kangaroo Rat habitat would be jeopardized.
PACE generated a geomorphology study of the Kangaroo Rat Island that spanned over 70 years. Historical photos of the study reach for the past 70 plus years were acquired for the analysis and all images had to be scanned, seamed and georeferenced based on historic landmarks. After the registration process of the historic photos was completed, PACE digitized the extent of the Kangaroo Rat Island per each acquired year. Then using GIS, the expansion and contraction of the island throughout the 70 years was compared and analyzed.