Highway Safety

Roadway Safety Improvement Projects
The Traffic & Safety Engineer handles the Roadway Safety Improvement Program (RSI). The RSI program has $10.5 million Federal Hazard Elimination Funds allocated to it for implementing improvements at locations on public roads where there is an accident history. Depending on the size of the improvement, 10 to 15 projects are programmed each year in the RSI program. There is a match ratio of 90/10, where the local entity is required to pay the 10% match.
Federal Section 402 - Highway Safety Projects
The Section 164 Safety Program provides traffic engineering services to local governments as well as paying for materials for signing improvements. Many requests are received each year for traffic related assistance from local governments who do not have traffic & safety engineering personnel on their staff.

To request to be included in the signing safety improvement program - click here.
South Dakota Strategic Highway Safety Plan

The mission of the South Dakota Department of Transportation (SDDOT) is to efficiently provide a safe and effective public transportation system. In order to provide a safe transportation system, the SDDOT and the South Dakota Department of Public Safety, in partnership with the Federal Highway Administration (FHWA), found it necessary to update the 2014 Strategic Highway Safety Plan (SHSP).  The updated plan, guided by the safety vision statement of:  Eliminate ALL deaths and life-changing injuries on South Dakota roads so everyone arrives home safely, identifies various strategies intended to reduce traffic fatalities to 100 or fewer and serious injuries to 400 or fewer by 2024.

Strategic Highway Safety Plan

South Dakota Vulnerable Road User Safety Assessment

Centerline Rumble Stripes
The South Dakota Department of Transportation will be placing Centerline Rumble Stripes (CLRS) on stretches of state highways with high traffic numbers. CLRS are a proven countermeasure to reduce the risk of cross centerline crashes such as head-on and side-swipe collision. Although these types of crashes represent a low number of overall crashes in South Dakota, they represent a significant number of severe crashes due to the high speed differential. CLRS are a low cost safety improvement that have been shown to reduce cross centerline crashes by 50 percent.

Centerline Rumble Stripe Facts

Every Life Counts - Partnering to Save Lives
  • Centerline Rumble Stripes (CLRS) are grooved patterns in the pavement placed on centerline that provide both an audible warning and a physical vibration to alert drivers that they are leaving the driving lane.
  • CLRS are a proven low cost safety improvement to reduce target crash types. Target crashes for CLRS are head-on, sideswipe opposing, and run-off-road left - statewide there were 352 (30% of state's total) fatal and serious injury crashes of these types on rural 2-lane roads between 2010 and 2014.
  • The South Dakota Strategic Highway Safety Plan identifies CLRS as a priority safety strategy for reducing head-on vehicle collision with a 60% reduction of this crash type.
  • SDDOT implemented CLRS guidelines in 2016 to reduce lane departure crashes systematically and proactively.
  • The guidelines recommend that CLRS be placed on rural, undivided roadways with daily traffic greater than 2,500 vehicles.
  • Lane Departure crashes occur on all types of roadways; however, there are some common factors that were used to determine roads covered in the guidelines:
    • Driver related - Young drivers, fatigued and drowsy drivers, distracted driving, and higher speeds.
    • Road and environmental related - Two lane, undivided roads; rural, high speed roads; high traffic volumes; horizontal and vertical curves.

Noise Concerns:

  • One of the designed intents of CLRS is to get the driver's attention through noise; this can be disturbing to residences near CLRS.
  • SDDOT CLRS guidelines allow flexibility in gapping rumbles near residences.
  • MnDOT conducted a research project to develop a CLRS pattern that has a significant reduction in external nuisance noise. The new CLRS pattern is called a Sinusoidal Rumble Design, or Mumble Strips.
  • Mumble Strip CLRS will be used in lieu of standard CLRS patterns on segments adjacent to residences.

The South Dakota DOT started initiating standalone shoulder rumble strip projects in 2010. Since these installations, SDDOT has seen a 20% reduction in fatal and serious injury run-off-road crashes.

Michigan DOT has shown a 50 percent reduction in all types of target crashes (head-on, sideswipe opposing, and run-off-road left) after statewide installation of centerline rumble strips on 5,400 miles of its rural, non-freeway highway system.
To learn more about CLRS in South Dakota:
Centerline Rumble Stripe Fact Sheet

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