Castle Rock council unanimously lowers speed limit on Crystal Valley Parkway to 35 mph

The Castle Rock Town Council unanimously approved a motion Tuesday to reduce the posted speed limit on Crystal Valley Parkway from higher posted limits to 35 miles per hour along the segment between Lake Gulch East/West and the roundabout at Crystal Valley Parkway and Plum Creek, citing pedestrian safety near parks and increasing local traffic.

Council member Deetz moved the change, saying, “I would like to change the speed limit to 35 in Crystal Valley Parkway.” The motion was seconded and carried by a roll-call vote with every councilmember voting in favor.

Why it matters: Council members described the change as a safety measure intended to slow drivers approaching the roundabout and the park area. Supporters said signage alone often does not change drivers’ behavior and that engineering changes — such as the roundabout already planned for the area — would have a larger effect, but a lower posted limit could reduce the top-end speeds until the physical improvements are completed.

What council discussed: Council members and staff debated the merits and limits of changing posted speeds without a formal engineering study. Dan, a public-works staff member who spoke to the council, told members the town typically follows the Manual on Uniform Traffic Control Devices and performs an engineering evaluation before formally changing speeds. He warned that ‘‘signs alone will not change the behavior’’ and that enforcement burdens on police often increase when speed limits are reduced without other calming measures.

Council member Deetz and other members said they hoped the change would dovetail with construction of a planned roundabout at the Crystal Valley interchange and other traffic-calming measures. Council member Bracken asked for speed-monitoring strips after the change so staff could collect data and determine whether the new limit influenced driver behavior.

Outcome and next steps: The motion passed unanimously. Council directed staff to install the new signs and to report back with speed data and any operational impacts on enforcement. Councilmembers said they expect the speed reduction to be supported by the upcoming physical changes, including the roundabout, and by additional monitoring.

Local context: Residents who live near Crystal Valley Parkway and several councilmembers cited pedestrian activity around a park and the growing local traffic as key reasons for the change. The posted-limits action applies only to the segment described at the council meeting; staff said any broader or longer-term changes should be based on an engineering analysis.