Write Up:

Motorists want to travel through work zones with as little inconvenience as possible. MoDOT works to minimize travel impacts by adjusting work times, using technology that provides valuable information to customers, and implementing innovative traffic‑control devices to promote efficient traffic flow. To measure the effectiveness of these strategies, MoDOT monitors the performance of work zones with the greatest potential to impact traffic each quarter. The goal is to minimize the number of times a work zone creates a traffic delay of 10 minutes or more.

In 2023, the highest number of delays and overall congestion occurred compared to the previous five years. Calendar year 2026 is trending higher for both the number of delays and overall congestion than 2025. When comparing year-to-date 2026 with YTD 2025, there is a 90% increase in the number of delays yet only a 35% increase in overall congestion. MoDOT has monitored 354 work zones, resulting in 855 work‑zone delays of at least 10 minutes and total congestion of 277 hours.

This quarter, geometric improvements on I‑70 in St. Charles County and the US 71 Bridge project in Kansas City were the largest contributing projects, causing 42 hours and 24 hours of congestion, respectively. These projects have contributed a total of 66 hours of the 277 hours (24%) of congestion this quarter. Pavement reconstruction and widening along I‑70 has contributed 118 hours of congestion. For the year, bridge improvement projects continue to be the largest contributor of delays at 137 hours (49%) of total congestion.

The target for cumulative statewide work‑zone congestion was set at 568 hours, the average of the previous three years of completed data. This target will remain a rolling three‑year average based on data from calendar years 2023–2025.

Purpose of the Measure:

Work zones are designed to allow the public to travel through them safely and with minimal disruptions. This measure tracks the performance of significant work zones.

Measurement and Data Collection:

Work zone impacts are identified using automated data collection and visual observations. An impact is defined as the additional time a work zone adds to normal travel. Impacts resulting in a delay of at least 10 minutes are included in this report. The targeted hours of work zone congestion are based on previous years' data and an acceptable tolerance of 30 total minutes for work zone congestion statewide. The target for this measure is updated quarterly.