Proposal to Hwy. 16 corridor explained

Mark Malone of the South Dakota Department of Transportation (DOT) presented the Hwy. 16 Neck Yoke Road proposal to a public audience of about 100 people Nov. 22.
The presentation was an opportunity to learn more about the project as well as to ask questions. Malone stressed that this is a proposal only at this point.
“I want to hear your concerns. Right now it’s a proposal. It’s lines on paper,” Malone said.
There are three safety factors the DOT considers when evaluating a project: condition of the road, the capacity of the road and safety.
Hwy. 16 was graded in the 1960s and the last service improvements took place in 2016. Average daily traffic (ADT) in 2026 is expected to be 16,000 east of Neck Yoke Road and 14,000 west of Neck Yoke. By 2050 that projected ADT rises to 20,500 and  18,000 respectively.
Crash history in the five-year period from 2017 to 2021 shows there have been 24 reported crashes with 13 of them involving animal hits. The remaining crashes consist of fixed objects off road,  angle intersection, side swipe overtake and angle no intersection crashes.
The statewide rated crash rate is 1.46, but for this corridor eastbound the rate is 2.06.
The proposed improvement to the corridor  includes constructing a reduced conflict intersection. This will be the first of its kind in the state although neighboring states like Nebraska and Minnesota use them in rural four lane highway settings.
Malone showed a video depicting what the intersection will look like once completed. While the video played, one attendee could be heard saying, “that makes a lot of sense.”
The reduced conflict intersection limits the number of cars passing the path of another car. The fewer decisions a driver needs to make the safer a roadway becomes. In general a reduced conflict intersection is a means to decrease broadside crashes. In this particular instance drivers on Hwy. 16 will continue on the corridor at the current speed limit with no changes.
It is only drivers that are looking to enter or leave from any of the side businesses or roadways that will be impacted.
For example, currently Reptile Gardens has three entryways. That will be reduced to one entrance. Also the three possibilities for turning east from Hwy. 16 will be reduced to one possibility: Neck Yoke Road.
Drivers from Neck Yoke traveling toward Hill City make a right onto Hwy. 16 and go immediately to the left hand lane and make a U-turn merging with Hwy. 16 traffic going toward Hill City.
Likewise, people traveling from Rapid City to Neck Yoke Road do so via a left hand turn lane.
“You’re taking that left turn from the minor leg (Neck Yoke) onto the high speed highway (Hwy. 16) and separating those two intersections so you’re not having to cross four lanes of traffic at once, just two. It’s all about reducing the conflicts at one point,” Malone said.
The proposal looks at the Reptile Gardens and Neck Yoke area only and does not have any changes to the Candyland section of the highway.
Other improvements include replacing the Spring Creek bridge, extending roadway lighting and adding right turn lanes.
Malone said there are plans to have a consistent corridor so that once people are used to it it will be no different from stopping at a stop sign or a stoplight. This may include work farther up Hwy. 16.
People in attendance had several concerns. Many felt the speed limit in this particular stretch of road was just too high.
One gentleman asked, “is it worth this money for the types of crashes that we’re seeing to just change the speed limit?”
Malone said working with an outside consultant that this is the best bang for buck along this corridor, although he did acknowledge when speed is reduced both severity and the possibility of the number of crashes go down. However, Malone explained that it’s proven in highway safety studies that people “get a feel” for what the speed limit of a road should be and regardless of posted signs end up driving that speed.
Other concerns about the project included  snow and raised medians, with one attendee noting, “this is a very dangerous place.” Campers were also an issue about which people raised questions.
Creative counter proposals from audience members included lowering the speed limit and putting up a temporary light during the summer similar to the one at Three Forks. Malone encouraged people to submit comments.
The DOT looked at an overpass possibility and said that idea was too complicated, requiring more right of way and taking more of the parking lot of Reptile Gardens. It also looked at a stoplight. However the cost was almost double due to the additional acceleration lane needed for trucks.
 The construction schedule for this project will take place primarily in 2026. However, post rally in 2025 will see crews working on the Neck Yoke and Reptile Gardens area during which time crossovers will facilitate traffic flow.
Pre-rally 2026  work will  take place on the westbound side of Hwy. 16 with two-way traffic occurring in the eastbound lane.
The DOT is proposing sensor type signals be used during the construction phase.
“It looks by far to be the most effective way to keep traffic moving,” said Malone.
Eastbound work on Hwy. 16 will take place post rally of 2026 with work scheduled to be completed in 2027 prior to July 4.
The DOT is accepting comments on the project through Dec. 9. Comments can be made via email to mark.malone@state.sd.us.
The entire proposal can be seen on the DOT website.