Fluvial Geomorphology to the Rescue
Cottonwood Creek is a small urban channel passing through Sandy Lane Park in east Fort Worth. The City of Fort Worth recently discovered that erosion had resulted in loss of park land and damage to City infrastructure, including the collapse of a portion of Sandy Lane Park Drive and a storm drain outfall.
Under an on-call fluvial geomorphological services contract with the City of Fort Worth, our team assessed the channel’s erosion and unstable areas, evaluated solutions, and identified feasible alternatives.
The team, led by Stephanie Coffman, fluvial geomorphologist, Fort Worth, investigated the site’s subsurface geology to an extent not usually seen in channel projects. The investigation revealed the presence of the Grayson Marl Formation on the channel bed and a buried paleo-channel composed of erodible reworked Woodbine Formation sediments. Understanding how these formations respond to channel processes was necessary for predicting the erosion patterns of the channel and provided the team with essential information for a successful stream stabilization design concept.
The information gathered from the geomorphic analysis, as well as a hydraulic analysis update performed by our stormwater team, provided critical data for the design. The study approach provided insight to complex site conditions that would have otherwise been overlooked. Information gathered during the geomorphic analysis was conveyed to the City’s design team, and the final design of stream stabilization features is underway.