Parnell Creek Subwatershed Site M-3 in Smithland, Iowa is a local government-owned dam that serves multiple purposes including fire protection, stock, and small fish pond maintenance, as well as flood risk reduction. Built in 1967 by the USDA NRCS, this earthen dam stands at a height of 42 feet and has a length of 572 feet, providing a storage capacity of 219 acre-feet and covering a surface area of 10.6 acres.

Located on the TR-Parnell Creek, this dam is regulated by the Iowa DNR and undergoes state permitting, inspection, and enforcement. With a hazard potential rated as low and a moderate risk assessment score of 3, this structure has not been rated for its condition yet. The dam has not been modified in recent years and does not have an Emergency Action Plan in place, but it meets state guidelines and has no inundation maps prepared.

Overall, Parnell Creek Subwatershed Site M-3 plays a crucial role in managing water resources in Woodbury County, Iowa. Enthusiasts of water resource and climate conservation will find interest in the dam's design, purpose, and regulatory oversight, as well as its potential impact on flood risk reduction and environmental protection in the region.