Hyde Park police say radar speed-trailer reduced speeds; data show majority still exceed posted limit

Hyde Park’s police chief reported to the city council on June 25 that a radar speed-calming trailer placed at 700 East at 356 North produced measurable slowing but also showed that a majority of recorded vehicles exceeded the posted limit.

City police said the trailer was deployed June 18 and retrieved June 24. “We placed it up on 700 East at 356 North there, and it was on the East side of the highway with the sign facing north,” the chief said during the meeting. “This particular trailer is known as a speed calming trailer… I’d set it at 30, and when people got to 31, the red and blue started to flash, and we did see a calming influence.”

Key findings presented by the chief and staff - Vehicles recorded: 6,455 (June 18–24). 3,045 (47%) were at or below the posted speed; 3,410 (53%) exceeded the posted speed. - Average speed recorded: 24.76 mph; fastest recorded: 50 mph. - 80th percentile speed: 29 mph. - Speed distribution: 2,116 of the 3,410 speeding vehicles were in the 26–30 mph range.

Council discussion highlighted measurement nuances: council members asked whether recorded averages were skewed by very slow speeds (cars leaving driveways or turning) and whether the device’s “closing” and “away” readings capture approach vs. departing speeds. The chief explained the unit measures heading “from the front” (approaching) and also records the direction moving away, and that the trailer’s lights flash only for approaching vehicles on the side where the lights are visible.

The chief recommended using the trailer data to guide signage and enforcement placement and said it also provides time-of-day and direction data that are useful for public works and grant applications. Council members requested additional locations and schedules for future deployments; the chief said the department has one modern unit with data capability and two older units with power issues.

What the data mean Council members and staff said the trailer demonstrated a calming influence for at least approaching vehicles and that the 80th percentile speed (29 mph) would, by engineering practice, imply a higher posted limit than currently desired by some council members (some argued for a 25 mph posting on that road). Chief and staff emphasized the trailer’s value for targeted enforcement and public-works planning rather than as a replacement for enforcement.

Sources and records Police provided the trailer report with the vehicle counts, speeds, and distribution used for the briefing. The chief said the department will continue to move the trailer to locations with high-speed complaints and will share future deployment schedules with the council.