I-90 Corridor in South Dakota

410 Miles From Prairie to Mountains

I-90 crosses South Dakota from the Minnesota border near Luverne to the Wyoming border near Spearfish, covering approximately 410 miles. The first 300 miles are flat prairie. Then the terrain changes. The Black Hills rise in western South Dakota, and what was a straight, flat highway becomes a route with grades, curves, and a fundamentally different driving character.

This transition is the defining feature of I-90 in South Dakota, and it catches transcontinental haulers who have been cruising flat terrain for hours.

Segment-by-Segment Guide

Eastern South Dakota: Sioux Falls to Mitchell

Sioux Falls is the I-90/I-29 interchange — the busiest junction in South Dakota. The city has multiple truck stops and full services. Mitchell (home of the Corn Palace) is the next significant service point eastbound.

Central South Dakota: Mitchell to Chamberlain

This stretch marks the beginning of the service gap that defines central I-90 in South Dakota. The Chamberlain area at the Missouri River crossing provides fuel and services, but between Mitchell and Chamberlain, options are slim.

The Missouri River Crossing at Chamberlain

Chamberlain sits at the Missouri River crossing, where the terrain changes from flat eastern prairie to the rolling landscape of central South Dakota. The bridge itself can be icy in winter, and the elevation changes on both approaches require attention after hundreds of miles of flat driving.

Central Gap: Chamberlain to Rapid City

:::tip This 190-mile segment between Chamberlain and Rapid City has the least truck stop density on I-90 in South Dakota. Fuel up at Chamberlain or plan to stop at Murdo or Kadoka — both small towns with limited capacity. Do not enter this segment with less than half a tank. :::

Towns with fuel along this segment: Murdo, Vivian, Presho, Kennebec, Kadoka, Wall. These are small towns, not truck stop hubs. Wall (near Badlands National Park) has more options than most.

Western South Dakota: Rapid City to Spearfish

The terrain transition hits here. After 300+ miles of flat prairie, the Black Hills introduce grades and curves that require a different driving posture. Rapid City is the primary service hub for western South Dakota with multiple truck stops. The Spearfish weigh station near the Wyoming border is the last checkpoint before entering Wyoming’s I-80/I-90 corridor.

Service Stop Reference

Winter Operations on I-90

I-90 across South Dakota faces the same prairie blizzard conditions as I-94 in North Dakota and I-94 in Minnesota. Open terrain, no windbreaks, and wind-driven snow create whiteout conditions where visibility drops to zero.

The central gap (Chamberlain to Rapid City) is especially problematic during winter storms because of the limited services. Being stranded in a blizzard between Murdo and Kadoka means a long wait for assistance.

Winter preparedness:

• Keep fuel tank above half at all times
• Carry 48-hour survival supplies
• Monitor SD511 for conditions and closures
• Stop at the next available town when conditions deteriorate
• Do not attempt the central gap during active blizzard warnings

Speed Environment

Cars on South Dakota interstates are posted at 80 mph. Check posted signs for truck-specific limits, which may vary. The speed differential between passenger vehicles at 80 mph and trucks at lower speeds creates a passing dynamic similar to Montana’s 15 mph gap, though South Dakota’s differential may be less extreme depending on the specific truck speed limit posted.

I-90/I-29 Interchange at Sioux Falls

The Sioux Falls interchange is the busiest junction in South Dakota and the gateway for traffic moving between the I-90 corridor and the north-south I-29 route (connecting to Iowa to the south and North Dakota to the north). Congestion around this interchange is the closest South Dakota gets to urban trucking challenges.

Insurance Implications

I-90’s long service gaps and high-speed environment create a risk profile that rewards adequate coverage. An incident in the central gap between Chamberlain and Rapid City means extended response times, and the 80 mph car speed environment means closing speeds are high. South Dakota trucking insurance at $1,000,000 CSL provides the coverage margin that this corridor demands.