West Mississippi Avenue Pilot Traffic Calming Project

These strategies are designed to slow down drivers and reduce their speeds.

• Narrowed Travel Lanes

  West Mississippi Avenue received a new asphalt surface this year. This allowed the city to install new striping that makes the travel lanes 11-feet in width.

• Speed Cushions

  Speed cushions are similar in shape and size to speed humps, but they include small gaps called “cutouts” that allow wider‑tracked vehicles, such as emergency vehicles, some trucks, and some buses, to pass through without being affected. Passenger vehicles, however, must still travel over the raised portion. Like a traditional speed hump, speed cushions are designed to be comfortable to drive over at around 20–25 mph. They are often preferred on primary emergency response routes or transit routes where a traditional speed hump may not be feasible.
  
  Six speed cushions will be installed between Pierce and Sheridan. The speed cushions will include wheel slots to allow West Metro Fire vehicles to travel through this segment without having to slow down significantly, resulting in minimal impact to the fire response. West Metro Fire has reviewed and approved the design for this pilot project.
  • Watch the speed cushion video to learn more.
    
    

• Median Islands

  Four median islands will be installed along the street’s centerline that visually narrow the roadway. Using vertical posts to delineate the island, the visual appearance of the lane narrows to encourage motorists to slow down. Vehicles will still be able to turn left at intersections.

• Pedestrian and Bicycle Crossings

  Two crossings, one at Marshall and one at Depew streets, will be installed to create greater safety for cyclists and pedestrians crossing West Mississippi by using median islands to provide a pedestrian refuge in the middle of the street.

Traffic count

Before installing these items, the city collected and documented the current traffic volumes and average speeds of vehicles on this stretch of roadway.

• On a typical weekday, a total of 14,771 vehicles travel in both directions on this segment. Traffic counts were taken May 22-23, 2025, just east of Marshall Street.
• The average speed was 33 mph, and 85 percent of the cars were going 42 mph or slower.
• During the traffic count, there were 1,976 vehicles on May 22 that exceeded the posted speed limit of 35 mph by more than 10 mph.

Once these items are fully installed, the city will evaluate their effectiveness based on changes in driver behavior, feedback and analysis of any crashes. The results of this analysis will also be posted here on the project’s webpage when they are available.

Crash information

The following data is from five years: April 1, 2021-March 31, 2026.

• 74 total crashes occurred on this portion of Mississippi. Of these 25 crashes resulted in 34 injuries to people, and the remaining 49 were property damage (or noninjury) crashes.
• The 74 crashes can also be classified by type, as follows: 26 broadside, 20 rear-end, 9 left turn, 6 fixed object, 5 head-on, 3 sideswipe, 2 bicycle, 1 overtaking, 1 pedestrian, and 1 other.
• 56 crashes occurred in the daytime, while 15 were at night, and 3 at dawn/dusk.
• 11 crashes involved alcohol or drugs with an at-fault driver.

West Mississippi Avenue Crash Summary

West Mississippi Avenue Crash Map
The data system stacks the crash symbols if they are coded to the same location, so there will be fewer than 74 dots or squares. Dots represent crashes involving only property damage, and squares represent injury crash locations.

Crash Dashboard from Denver Regional Council of Governments
Zoom in on the map for more information on each crash in your area of concern.

Crash data for similar streets
This data shows this segment of Mississippi has more injury crashes than West 10^th, West First, West 14th, West Florida, West Jewell and West Yale avenues between Pierce and Sheridan.

This project is also part of the Vision Zero Action Plan for Jefferson County, which is an effort by the county and all of the cities within it to strive toward zero deaths or serious injuries from traffic crashes.

This pilot project also follows the city’s action to reduce the speed limit to 20 mph on residential neighborhood streets. These are the local streets that directly serve homes and encourage walking, social connections and a sense of community. This 20 mph speed limit does not apply to larger collector and arterial streets that carry more traffic such as West Mississippi Avenue. Learn more about this at LakewoodCO.gov/SafeStreets