South Dakota officials have marked the start of a $290 million project to replace the Platte-Winner Bridge over the Missouri River, a major transportation link on S.D. Highway 44 that connects communities in the south-central part of the state.
Gov. Larry Rhoden, South Dakota Department of Transportation (SDDOT) Secretary Joel Jundt and federal, state and local officials participated in a groundbreaking ceremony Oct. 22, 2026, in Platte, S.D. The existing bridge opened in 1966 and is the longest bridge in South Dakota.
Ames Construction of Burnsville, Minn., is the primary contractor for the replacement project. Construction is scheduled to continue through 2031, with work expected to begin in early 2027.
The new bridge will be 36 ft. wide, including shoulders, compared with the existing structure's 28-ft. width. The additional width is intended to improve safety and reliability along the highway corridor.
The Platte-Winner Bridge is one of only nine bridges crossing the Missouri River in South Dakota and serves as an important route for regional transportation, freight movement and access to recreational areas. Without the crossing, travelers would have to drive an additional 81 mi. to cross the Missouri River, according to SDDOT.
Existing Bridge to Remain Open
The existing bridge will remain in service throughout construction. It will not be removed until the replacement bridge and associated highway work are complete.
Motorists should expect occasional temporary traffic impacts as construction progresses. These could include lane closures, alternating one-way traffic and brief stops to allow construction equipment to move safely through the work zone. SDDOT anticipates that these disruptions will be limited.
The replacement project is intended to provide a new structure with a planned 100-year service life, extending the useful life of this important Missouri River crossing.
The project received a $65 million federal grant through the Federal Highway Administration's Competitive Highway Bridge Program, announced in April 2026. South Dakota also previously secured $25 million in federal funding through congressional directed spending to support the project.
For more information, visit dot.sd.gov.
