Jefferson is a gravity dam located in Jefferson, Wisconsin, along the Rock River. Completed in 1842, this dam serves primarily for recreation purposes, providing a surface area of 122 acres and a maximum storage capacity of 650 acre-feet. With a hydraulic height of 6 feet and a structural height of 11 feet, Jefferson has a controlled spillway with a width of 182 feet. The dam has a low hazard potential and was last inspected in October 2013, with a satisfactory condition assessment reported in January 2014.

Managed by the local government, Jefferson is regulated by the Wisconsin Department of Natural Resources, with state permitting, inspection, and enforcement in place. The dam has undergone modifications in 1915 and 2001. Despite being categorized as having a very high risk level, measures for risk management and emergency preparedness are not explicitly mentioned in the data. The dam is within the jurisdiction of Rep. F. James Sensenbrenner Jr. (R) and falls under the supervision of the Rock Island District of the US Army Corps of Engineers.

Enthusiasts of water resources and climate in the Jefferson area can appreciate the historical significance and recreational opportunities provided by the Jefferson dam. With its long-standing presence and vital role in water management along the Rock River, ensuring the continued safety and effectiveness of Jefferson remains a priority for local authorities and regulatory agencies. The data highlights the importance of regular inspections, maintenance, and risk assessment to mitigate potential hazards and protect the surrounding community and environment.