By: Megan Mills Contributing Author
Missouri highways will soon be sporting a new look, with wider, longer-lasting pavement markings that will make driving Missouri roads safer. Along with being safer, the new system uses innovative, cost-effective products.
Thanks to the recent passage of Amendment 3—the Smooth Roads Initiative—the Missouri Department of Transportation (MoDOT) received additional funds to focus on improving Missouri’s roads and making them “Smoother, Safer, Sooner,” according to the slogan. The new pavement-marking system is just one way that MoDOT plans to achieve the safer part of the program.
“MoDOT is making roads safer by improving signs, adding miles of guard cable and installing emergency reference markers,” said MoDOT Director Don Hillis. “Pavement markings, like paint and tape, are the final piece of the puzzle in providing the best roadway-visibility plan for Missouri.”
Until now, MoDOT did not have a comprehensive pavement marking or striping plan. A mix of materials were used to stripe different roadways, including waterborne paint, epoxy paint, polyurea, tape and beads.
Currently, MoDOT spends $31 million annually on pavement markings and will save approximately $2 million over eight years with the new system. While the savings are not huge, the new system’s safety benefits are significant.
The new elements of the pavement-marking system are more reflective and durable to improve roadway visibility, reduce crash potential and provide for uninterrupted traffic flow.
MoDOT’s pavement-marking plan was approved for implementation in July. The system was first implemented in August to newly paved roadways and will be applied to 2,200 miles of new pavement by the end of 2007.
The plan
MoDOT tested nine products on a test deck on I-54 in Callaway County to determine the best components of the new pavement-marking system. Tested products included tapes, liquid markings, various bead combinations, rumble-edge lines and rumble strips. From this research, MoDOT developed two pavement-marking systems, one for major roads and one for minor roads. Major roads are defined as the top 5,500 miles of roads, which serve 76% of the Missouri traffic volume.
On major roads, pavement markings will include rumble strips, epoxy-paint edge lines and waffle-tape center lines. Multilane divided roadways will have epoxy edge lines and waffle tape, and multilane undivided roadways will have the rumble stripes. Two-lane roadways will have epoxy and rumble edge lines and will be marked with a fourth-generation paint system.
“The pavement marking industry is constantly evolving, and MoDOT will keep abreast of these changes by continuing to test new materials and processes,” Hillis said. “We want to continue to provide the safest possible roadways for Missouri motorists.”
Rumble stripes are MoDOT’s new solution to providing a more visible edge line to alert motorists early that they are leaving the travel lane. MoDOT hopes rumble stripes will help avoid some possible crashes and injuries. A rumble stripe is the combination of a milled rumble strip and an epoxy-paint edge line. The noise and vibration of the rumble strips alert motorists they are on the shoulder, and the edge line paint enhances its visibility.
MoDOT has used epoxy paint since 2000, but now it will be used on all the major roads in the state. The paint used in the rumble stripes is fairly durable and will only need to be repainted every three to four years. The stripes also can be repainted without removing the existing paint. Even though it is more expensive than some other paint, it lasts longer and helps keep crews off the road more. That means fewer disruptions to traffic flow.
The new waffle tape will be wider than the previous 4-in. center-line markings and will be used on major roads. The 6-in. center-line tape has a raised pattern and a high level of reflectivity, which will improve visibility for motorists, especially in wet or night conditions. Based on Minnesota’s experience with this product, MoDOT expects the tape to last up to eight years, unlike current methods, which require yearly maintenance. The tape will be installed in a groove to protect it from snowplows.
Fourth-generation paint was tested in one section of the state and will now be used statewide on the department’s minor road system—approximately 27,000 miles of roads. It is acrylic-based and more durable than some other paints. This was the best, most cost-effective choice for these roads, and because it lasts up to two years, crews will only need to repaint every other year.
MoDOT’s new pavement-marking system allowed the department to provide options for good visibility in wet and night conditions, so the department has decided to discontinue installing any raised pavement markers. Raised pavement markers were installed in 1996 to provide motorists with increased roadway visibility, but some of them have become loose in the pavement. Because of this, existing raised markers will remain in place until the road is resurfaced, and MoDOT will conduct routine inspections to ensure they are removed before becoming a safety concern. Annual physical inspections of them include striking the markers individually with a hammer, and if they move, the crews remove them.
The rest of the puzzle
Besides pavement markings, MoDOT has made changes in other areas to make Missouri roadways safer. These efforts include more visible emergency reference markers, median guard-cable installation, and installation of reflective markers on median barriers.
Emergency reference markers are mile markers placed along the outside shoulder to improve delineation and used to convey information to drivers about their location on the interstate for navigation and emergency situations. The reference markers are located every tenth of a mile, so motorists will always be in sight of a sign.
The new signs will tell the driver their direction of travel and route number. They also help motorists determine the edge of a roadway in poor visibility. The new markers are larger, more durable and easier for drivers to see. The markers will last 10 years instead of two (like the flexible delineators that have been used in the past) and could save MoDOT more than $200,000 a year.
MoDOT has already installed or is currently completing approximately 160 miles of guard cable on highways throughout the state. Several projects are planned over the next two years to add more than 430 additional miles of guard-cable barriers on interstate highways.
“Median guard cables are effective in reducing the number of cross-median crashes both disabling and fatal and they are cost-effective,” said MoDOT State Traffic Engineer Eileen Rackers. “The cables are hit more often, but more lives are being saved.”
The most common types of interstate median barriers are guard cables, concrete barriers and guardrails. Missouri chose guard cable because the cost of installation is 40% less than guardrail and 80% less than concrete barrier. Additionally, guard cables produce less damage to vehicles and their occupants because of their flexibility.
Effective this past July, guardrails, guard cables and median barriers now are required to have reflective materials placed 50 ft apart if within 2 ft of the shoulder. This will provide motorists with guidance through areas with obstacles close to the roadway.
MoDOT’s new pavement-marking system is the last piece in the puzzle the department has been putting together to make Missouri roads smooth, safe and as soon as possible. By implementing the new system, updating emergency reference markers, installing guard cable and improving reflective materials on median barriers, MoDOT hopes to make roadways safer for all Missourians.
The department also hopes to make the roads smoother by resurfacing 2,200 miles of roadway throughout the state by 2007. Some major roadways being resurfaced include I-70 and I-44.
MoDOT also set a goal to complete most of its construction projects sooner by increasing the number of construction zones and encouraging early project completion. Missouri roadways will have more than 800 active construction projects this year.
“It’s all about providing the safest, smoothest roads we can as quickly as possible,” Hillis said. “We want Missourians to be proud of their highway system, and it’s our job to do the most we can with the funds we have. We hope by implementing these latest changes, everyone will see a difference when they drive our roads.”
The new signs will tell the driver their direction of travel and route number. They also help motorists determine the edge of a roadway in poor visibility. The new markers are larger, more durable and easier for drivers to see. The markers will last 10 years instead of two (like the flexible delineators that have been used in the past) and could save MoDOT more than $200,000 a year.
MoDOT has already installed or is currently completing approximately 160 miles of guard cable on highways throughout the state. Several projects are planned over the next two years to add more than 430 additional miles of guard-cable barriers on interstate highways.
“Median guard cables are effective in reducing the number of cross-median crashes both disabling and fatal and they are cost-effective,” said MoDOT State Traffic Engineer Eileen Rackers. “The cables are hit more often, but more lives are being saved.”
The most common types of interstate median barriers are guard cables, concrete barriers and guardrails. Missouri chose guard cable because the cost of installation is 40% less than guardrail and 80% less than concrete barrier. Additionally, guard cables produce less damage to vehicles and their occupants because of their flexibility.
Effective this past July, guardrails, guard cables and median barriers now are required to have reflective materials placed 50 ft apart if within 2 ft of the shoulder. This will provide motorists with guidance through areas with obstacles close to the roadway.
MoDOT’s new pavement-marking system is the last piece in the puzzle the department has been putting together to make Missouri roads smooth, safe and as soon as possible. By implementing the new system, updating emergency reference markers, installing guard cable and improving reflective materials on median barriers, MoDOT hopes to make roadways safer for all Missourians.
The department also hopes to make the roads smoother by resurfacing 2,200 miles of roadway throughout the state by 2007. Some major roadways being resurfaced include I-70 and I-44.
MoDOT also set a goal to complete most of its construction projects sooner by increasing the number of construction zones and encouraging early project completion. Missouri roadways will have more than 800 active construction projects this year.
“It’s all about providing the safest, smoothest roads we can as quickly as possible,” Hillis said. “We want Missourians to be proud of their highway system, and it’s our job to do the most we can with the funds we have.”
About The Author: Mills is an assistant outreach coordinator with MoDOT; phone 573/526-4141.
