Kalamazoo Road Diets Show Safety Benefits on City Streets

Published on October 23, 2026

The City of Kalamazoo’s efforts to calm traffic and make streets safer continue with implementing traffic-calming measures across the city to protect not only motorists but pedestrians and bicyclists as well.

Kalamazoo’s crash frequency has declined substantially. During a four-year period from 2016 through 2019, the City experienced 14,507 reported traffic crashes, representing an annual average of approximately 3,627 crashes. By comparison, the City recorded 2,808 crashes in 2025. This represents a reduction of approximately 819 crashes annually – 22.6 percent compared with the historical baseline.

Through the adoption of the City’s Safe Streets for All Safety Action Plan, Kalamazoo maintains its commitment to further reducing crashes and enhancing a safe network for walking, biking, riding, and driving throughout the city. The Safe Streets for All Action Plan is a continuation of work that began in 2024 and also unlocks additional federal funding for infrastructure improvements.

Among the Safe Streets for All’s measures is the implementation of “road diets” that change four-lane streets to three lanes. Three-lane conversions have already occurred on Whites Road as well as on Oakland Drive. City traffic crews have just wrapped up a road diet on Portage Street along a stretch of Portage Street from Stockbridge Avenue south to East Cork Street. The next road diet project will take place in 2027 on Cork Street between Westnedge Avenue and Portage Street, thanks to a $750,000 federal highway safety grant just approved by the Kalamazoo City Commission.

Four-lane to three-lane conversion: safety outcome

To evaluate the effectiveness of three-lane conversions on Portage Street, Whites Road, and Oakland Drive, traffic engineers reviewed nearby construction projects that affected traffic volume, and conducted analysis of the before-construction years 2017, 2018, and 2019 on those thoroughfares. They also compared the analysis after 2025 on those thoroughfares and through September this year.

Their studies show three-lane conversions remain associated with fewer crashes even after accounting for changes in traffic volumes. The 2026 year-to-date check remains below the pre-conversion same-date baseline, especially outside signal influence areas.

An interpretation of the findings shows that: 1) While traffic exposure declined about 13 percent, the exposure-normalized crash rate declined about 30 percent; 2) When crashes within 250 feet of traffic signals are removed – along with the corresponding roadway length from the exposure calculation – the 2025 crash rate declines about 59 percent; and 3) Through September 11 this year, the corridors had 56 crashes – 13 percent below the 2017–2019 same-date average of 64.7 crashes. Outside the 250 ft signal areas, 2026 year-to-date shows 13 crashes – 43 percent fewer – versus a before same-date average.

“Road diets work,” said Dennis Randolph, public works manager and traffic engineer for the City of Kalamazoo, “and they reduce vehicle crashes by 30 to 60 percent. For many years, streets with two, four, or six lanes have been recognized as higher-crash streets in cities, especially when there are many intersections and driveways, such as Portage Street, because left turns tend to block the center-most lanes. The more left turns, the more blockages, weaving, and lane-changing by drivers going around the turning vehicles. This trend has been clearly evident on Portage Street, resulting in crashes.”

Portage Street road diet

Portage Street is now one lane in either direction between Stockbridge Avenue and Cork Street. The road diet project also includes the placement of bike lanes on both sides of Portage Street as well as pedestrian islands for easier and safer intersection-crossing in any direction.

“Our primary objective on Portage Street is to reduce crashes,” said Randolph. “To do this, we must address speed. Speeding causes crashes, and the faster you go, the more severe the crash. When we reduce crashes or the potential for crashes, we reduce fatalities, crippling injuries, the demand for emergency room and emergency services, repair costs for damaged vehicles, lost time for work and wages, and a host of other costs that burden people.”

City traffic studies show that prior to the Portage Street road diet, the average mile-per-hour speed from Stockbridge Avenue to Cork Street ranged in the mid-30s, with the 85th percentile near 40 mph. To address speed concerns, City traffic crews have implemented several recognized and proven crash countermeasures. Together, these countermeasures make Portage Street safer for car and truck traffic, pedestrians, bicyclists, and buses and their passengers.

• Pedestrian islands: They provide a refuge area for pedestrians crossing the street. They also make it harder for drivers to violate city ordinance and state vehicle codes by using the center-left turn lane to pass.
• Bus lanes: Portage Street is on a METRO route. Traffic crews have marked bus stops where buses can discharge passengers while still allowing traffic to pass safely. The marked bus stops also warn drivers that people may be getting off a bus and trying to cross the street and also tell motorists to watch out for pedestrians.
• Optical Speed Markers: These white blocks are painted on the turn lane near Alcott Street and provide an optical clue for drivers to slow down. They are relatively new to this region but have been used for years around the country and throughout the world.
• Bike lanes: The elimination of a driving lane and resulting available space allowed markings for bicycle traffic. On Portage Street, much of the bike lane is buffered, which provides additional separation between cars and bicycles.
• Reduced lane width: For many years, it has been known that the wider a traffic lane, the more crashes that happen. This goes back to the basic speed relationship: wider lanes make speeding easier; the faster motorists go, the more crashes occur, and the faster they go, the more severe the crashes. Not only are the narrower lanes safer, but they’re also cheaper to build and contribute to street sustainability by using fewer materials and less salt in the winter.

City traffic crews anticipate that it may take two to three weeks for traffic (and drivers) to settle into the new configuration on Portage Street, and eventually they expect only a 1- to 2-minute increase in travel time. “The trade-off,” Randolph said, “is a much safer street.”

Cork Street road diet

The $1.15 million three-lane conversion project on Cork Street is set to begin next spring and continue through the fall. The project involves adding several pedestrian islands and bike lanes along each side of the road. The project also includes the installation of rectangular rapid flashing beacons along Cork Street at Park Street, Rose Street, Ash Street, and Burke Street. Other street infrastructure will take place as well, including permanent signing and pavement markings.

Kalamazoo remains steadfast in implementing traffic safety and calming measures across the city in addition to road diets. These include lane elimination and narrowing, roundabouts, traffic circles, bike lanes and cycle tracks, enhanced pedestrian crossing lighting and signing and refuge islands, dynamic signal timing, audible pedestrian crossing signals, signal backplates, changing YIELD signs to STOP signs, adding STOP signs to uncontrolled intersections, general traffic signing upgrades, and speed humps.

“Each of the safety and calming measures we’ve implemented brings its own specific safety benefit,” said Randolph. “By tailoring these devices and measures to specific crash and street characteristics at locations around the city, we are able to maximize safety overall to our street system. Our emphasis on the number of people we can prevent from death or getting seriously injured and needing medical attention will always be our primary objective.”