Upper Dam, located in Gresham, Wisconsin, along the Red River, is a gravity dam primarily used for hydroelectric power generation and recreation purposes. Built in 1883, this historic structure stands at a height of 18 feet with a hydraulic height of 35 feet, providing a maximum storage capacity of 1300 acre-feet. The dam spans 289 feet in length and has a surface area of 215 acres, serving a drainage area of 147 square miles.

Managed by the local government and regulated by the Federal Energy Regulatory Commission, Upper Dam has a low hazard potential and a very high risk assessment rating. Despite its age, the dam has not undergone recent condition assessment, with the last inspection conducted in July 2017. The controlled spillway, with a width of 113 feet, is designed to handle a maximum discharge of 2600 cubic feet per second, ensuring the safety and stability of the structure in case of emergencies.

For water resource and climate enthusiasts, Upper Dam represents a blend of historical significance, renewable energy production, and recreational opportunities. As a vital part of the local ecosystem and infrastructure, this gravity dam continues to play a crucial role in water management and conservation efforts in Shawano County, Wisconsin.