Nowak Dam, located in Magnolia, Iowa, was completed in 2001 by the NRCS with a primary purpose of grade stabilization along TR-Allen Creek. This earth dam stands at 38 feet tall and spans 520 feet in length, with a maximum storage capacity of 18 acre-feet. The dam, built on a stone core and soil foundation, serves a drainage area of 0.15 square miles and has a low hazard potential.

Although Nowak Dam is not regulated by the state and has not been inspected or rated for condition, it is considered to have a moderate risk level. The dam features an uncontrolled spillway with a width of 2 feet and has not been modified since its completion. Despite lacking emergency action preparedness measures, the dam serves as a critical infrastructure for managing water resources in the region and mitigating potential flood risks along the TR-Allen Creek. For water resource and climate enthusiasts, Nowak Dam represents a noteworthy example of a privately owned structure contributing to the overall resilience of the local watershed.