Project Name: Glendive, Montana Flood Risk Management Feasibility Study
Location: City of Glendive, Montana
Authority: Section 205 of the Flood Control Act of 1948, as amended
Non-federal Sponsor: City of Glendive and Dawson County
Current Phase: Feasibility

Study Overview

City of Glendive and Dawson County officials have partnered with the U.S. Army Corps of Engineers, Omaha District (Corps) to conduct a Section 205 Flood Risk Management Feasibility Study (Study) to investigate alternatives to reduce flood and life safety risks in the community of Glendive, Montana.  The City of Glendive is in Dawson County in eastern Montana along the Yellowstone River approximately 90 miles upstream from the river’s confluence with the Missouri River.  Section 205 of the 1948 Flood Control Act authorizes the Corps to study, design, and construct small flood control projects in partnership with non-Federal government agencies, such as cities, counties, special authorities, or units of state government.  Projects are planned, designed, and constructed under this authority to provide a complete flood control project.  Each project must be economically justified, environmentally sound, and technically feasible. 

Flooding, typically from ice jams, presents numerous risks to residents and business owners in Glendive.  Damaging ice jam floods have occurred on the Yellowstone River in Glendive 30 times since 1890 including major ice jam floods in 1899, 1920, 1936, 1969, 1986, and 1994.  The West Glendive Levee, completed in 1959, was constructed by the Corps (Garrison District) to provide protection from flooding on the Yellowstone River.  The levee was designed to protect against an open water flood discharge of 200,000 cubic feet per second and ice-affected flooding with 3 feet of freeboard. In the 1980 Flood Insurance Study (FIS) the hydrology equates 200,000 cubic feet per second (cfs) to a 320-year return interval.  However, large open channel flows are not the biggest threat to this levee.  Ice Jams, especially during lower flows, cause a much more significant threat to overtopping the levee because they can block channel flows and result in rapidly increase river stages.  The 1980 FIS accounts for the significance of the ice jams and refers to the stage of the flood, rather than the type of flow, for recurrence intervals.

There are two objectives identified for this study:  1) Reduce the risk of flood damages in the Glendive reach of the Yellowstone River, and 2) Reduce the risk of life loss due to flooding in West Glendive.  The Corps conducts water resource planning studies using a structured decision-making process that involves identifying problems and opportunities, inventory and forecast of future conditions, formulating alternative plans, evaluating and comparing the plans, and selecting a recommended plan.  Planning studies also follow a concurrent National Environmental Policy Act (NEPA) process.  This Study will include an Environmental Assessment to comply with NEPA.