Toponce Ditch Dam Lower, located in Caribou, Idaho, plays a crucial role in irrigation, serving as a vital water resource for the surrounding area. This earth dam, constructed with a stone core, stands at a height of 18.1 feet and has a storage capacity of 78 acre-feet. The dam is regulated by the Idaho Department of Water Resources, ensuring proper inspection, permitting, and enforcement measures are in place to maintain its integrity and functionality.

The dam, situated on the Portneuf River and Toponce Creek, has a spillway type of "Uncontrolled" with a slide (sluice gate) for outlet gates. Despite its low hazard potential and fair condition assessment, the risk assessment indicates a moderate risk level. The last inspection in July 2018 revealed no significant issues, with a scheduled inspection frequency of every five years. With its historical significance and ongoing role in sustaining agricultural activities in the region, Toponce Ditch Dam Lower remains a crucial piece of infrastructure for water resource management in Idaho.

As a private-owned structure, Toponce Ditch Dam Lower's primary purpose of irrigation underscores its importance in supporting local agriculture and maintaining water supply reliability. With its unique design and location, this dam serves as a key component in the water management system of the area, contributing to the economic and environmental sustainability of the region. Despite being classified as having a moderate risk level, the dam's overall condition is deemed fair, highlighting the ongoing need for regular monitoring and maintenance to ensure its continued functionality and safety for the community.