The T&Y dam and diversion structure is located on the Tongue River about 20 miles upstream of the confluence with the Yellowstone River. The diversion dam is approximately 10 feet high and provides the head necessary to divert up to approximately 240 cfs. The existing facility needed to be replaced due to its age, high maintenance costs associated with large amounts of sediment, and the passage of significant numbers of fish into the T&Y Canal.

SEH, in close consultation with the Irrigation Company representatives, the Bureau of Reclamation, and the State of Montana, was responsible for establishing the size, location, configuration and physical characteristics of all improvements. SEH also prepared detailed construction drawings that included a site plan, demolition drawings, grading plans and sections, facility layout and dimensions, structural plans and sections, and details for the new facility.

Features

• Removed the existing facility
• Constructed a new diversion structure incorporating features to reduce problems associated with silt diversion and deposition, and a fish louver to reduce the passage of fish into the canal
• Repaired the existing dam, removed a wood and timber piling retaining wall and replaced it with a sheet pile structure

SEH Services

• Designed dam and diversion structure
• Prepared construction drawings and technical specifications
• Provided complete construction and materials technical specifications
• Developed complete project manual