Fountain Creek, a tributary to the Arkansas River, is located along the Colorado Front Range. Over the last 100 years, considerable changes in land use and water use have occurred within the Fountain Creek watershed. To meet the needs of the growing population, water is imported from outside the watershed by means of trans-mountain diversions, and most recently, the Southern Delivery System (SDS). The SDS brings water from a reservoir on the Arkansas River to Colorado Springs for municipal use and returns the treated wastewater back to the Arkansas River via Fountain Creek. Consequently, the total volume of runoff in Fountain Creek has increased over time. To better understand the extent to which increases in streamflow may influence the physical characteristics of Fountain Creek, the USGS partnered with Colorado Springs Utilities to monitor annual geomorphic changes over time.
Beginning in 2020, the USGS began using drone-based light detection and ranging (lidar) to map 10 study areas along Fountain Creek, which have been monitored using traditional survey methods since 2012. Drone-based lidar was chosen for this project because it provides much higher resolution data and, compared to traditional survey methods, can be completed much faster. For example, mapping a 20-acre study area (shown in the photo) using traditional survey methods took 9 person-days of work and resulted in 3,000 topography points, whereas mapping that same study area with drone-based lidar took 20 minutes and resulted in 46 million topography points. The higher resolution data provided by drone-based lidar will enable scientists to detect small-scale changes in topography that can potentially add up to large changes in sediment volume. These higher resolution data can be used to better identify the type and cause of geomorphic change along Fountain Creek, enabling land managers to improve remediation or restoration strategies.
Geomorphic Change Detection Using Drone-based Lidar on Fountain Creek, Colorado