Gsdd No B-12 (Gc Gs 4) is a local government-owned debris control dam located in Atchison, Kansas along the Grasshopper Creek-TR. Built in 2002 by USDA NRCS, this earth-type dam stands at a height of 25.4 feet and has a length of 750 feet, providing a storage capacity of 381.1 acre-feet. With a low hazard potential and a moderate risk assessment rating, this structure plays a crucial role in managing debris and protecting the surrounding areas from potential flooding events.

Managed by the Kansas Department of Agriculture, this dam is regulated, permitted, inspected, and enforced by state authorities to ensure its safe operation. The primary purpose of Gsdd No B-12 is debris control, with an uncontrolled spillway type and a maximum discharge capacity of 1327 cubic feet per second. Despite its low hazard potential, the dam has not been rated for its condition assessment, indicating the need for further evaluation and maintenance to uphold its functionality and safety standards.

Situated in the Rock Island District, Gsdd No B-12 serves as a vital infrastructure for water resource management in the region. With its strategic location and design features, this dam contributes to the overall resilience of the local watershed, highlighting the importance of effective debris control structures in mitigating the impacts of climate change and enhancing water security for communities in Atchison, Kansas.