Four bidders, a $161 million spread between high and low, and a winning number about $40 million over the engineer’s estimate. That’s the price of rural heavy civil right now, and South Dakota just paid it.
The South Dakota Transportation Commission on Aug. 25 selected Burnsville, Minnesota-based Ames Construction for a $290 million design-bid-build package to replace the State Highway 44 Platte-Winner bridge over the Missouri River, plus a smaller bridge in Douglas County. SDDOT calls it the largest project the department has ever led.
The bid tab
Ames came in at roughly $40 million above the state’s estimate on the Platte-Winner span. Lunda Construction bid $306 million. Kraemer North America bid $313 million. An entity called Platte-Winner Constructors bid $451 million. On the smaller Douglas County bridge Ames bid $652,000, about $64,500 under estimate.
That split is the interesting part. The same contractor priced a small conventional bridge below the state’s number and a large remote one 16% above it. The overage isn’t a bidding-market failure. It’s a specific read on a specific job.
SDDOT spokesperson Julie Stevenson was unusually direct about why: “the size and complexity of the project, current construction-market conditions for both materials and labor, and the project’s remote, rural location.” Agencies don’t often name rural location as a cost driver on the record.
What’s being built
The replacement is a steel girder bridge on drilled shafts, about 5,770 ft long, widened from 28 to 36 ft. The existing 5,655-ft bridge opened in 1966 and has been plagued by landslides on its alignment that have cost millions in repairs. Traffic opens in June 2030 and the old bridge comes down in November 2031.
Landslide-prone alignment is why the drilled shafts matter. Geotechnical uncertainty on a slope that has already moved is the kind of risk that shows up as contingency in a lump-sum bid, and with four bidders spread across $161 million it’s clear they priced it differently.
A useful data point
A 16% overage against the engineer’s estimate on the largest job a state DOT has ever let is a clean signal for anyone forecasting rural heavy-civil pricing. It’s also a reminder that estimating departments sized for $50 million jobs don’t automatically scale.
Larger crossings are running into the same forces from the other direction. The Sagamore Bridge replacement on the Cape Cod Canal carries about $2.1 billion for a single span, assembled from a $993 million FHWA Bridge Investment Program award, a $372 million Mega Grant, Army Corps money and state funds, precisely because no single source covers a bridge at that price anymore.
The “largest project the department has ever led” claim and the explanation for the overage are SDDOT’s.