Located in Marshall, Kansas, the Gs Dd 7-31b (Vermillion Creek) dam is owned and regulated by the local government, with oversight from the Kansas Department of Agriculture. This earth dam, with a height of 32 feet and a length of 900 feet, serves primarily for flood risk reduction along Robidoux Creek. The dam has a storage capacity of 465.3 acre-feet and a drainage area of 1.22 square miles, with a maximum discharge of 1560 cubic feet per second.

Despite its low hazard potential, the dam is considered to have a moderate risk level, with a risk assessment score of 3. The condition of the dam has not been rated, and there is no information available on its last inspection date or emergency action plan status. The dam does not have any outlet gates or associated structures, and there have been no modifications to the dam in recent years. Overall, the Gs Dd 7-31b (Vermillion Creek) dam plays a crucial role in mitigating flood risks in the area and is subject to regular state inspection and enforcement to ensure its safety and effectiveness.