The project: IMEG designed the Four Horns Dam Reconstruction project. Scope of work: The project included a new 6-mile access road, dam modifications (including the installation of 60-inch and 84-inch inlet and outlet pipes with extensive earthwork), and a new concrete spillway and structures.

Safety improvements: Spillway reconstruction, embankment improvements, and downstream irrigation channel improvements will provide additional reservoir storage and will decrease the risk of dam failure.

Project tasks: Include topographic and bathymetric survey, geotechnical investigation, design Value Engineering Study, Risk Reduction Analysis, and preparation of bid documents. IMEG also provided wetland delineation and mitigation planning, permitting, proposed right-of-way mapping, and Environmental Assessment development through local Browning consultant Indian Country Environmental Associates.

Tribal relevance: Blackfeet Nation, through a P.L. 93-638 contract with the Bureau of Indian Affairs (BIA), contracted project design to IMEG. IMEG worked extensively with the Tribe and the BIA to develop the project. Tribal partners included the Blackfeet Tribal Transportation Program for access road right-of-way map development and project coordination, Tribal Historic Preservation Officer, the Blackfeet Environmental Office, and Blackfeet Fish and Game.

The outcome: Tribal surveyors assisted with the topographic survey of the dam and downstream canal. Because the topographic survey was completed under budget through the assistance of the Blackfeet Tribal Surveyor, the Tribe could complete additional tasks outside of the scope of work, including cadastral survey for Right-of-Way acquisition along the access road.