Eis is a privately owned Earth dam located in Manitowoc, Wisconsin, along the Tr- West Twin River. Constructed in 1969 by the USDA NRCS, this dam stands at a height of 20 feet and has a length of 380 feet, providing a storage capacity of 100 acre-feet. With a low hazard potential and a moderate risk assessment rating, Eis serves a primary purpose of "Other" and is designated as an uncontrolled spillway type.

Managed and funded by the Natural Resources Conservation Service, Eis does not have a state regulatory agency overseeing its operations or inspections. Despite lacking a condition assessment, this dam has been deemed to have a moderate risk level, indicating the need for risk management measures to be put in place. With a history dating back over 50 years, Eis remains a vital structure in the region, contributing to water resource management and climate resiliency efforts in the area.