Boulder

• 28th Street improvements — Pearl to Iris: This project will improve multimodal travel along 28th Street from Pearl to Iris. Northbound 28th and Valmont Road RTD Stop #17992 serving 205 and BOLT routes will be temporarily relocated to just south of the Valmont intersection until Dec. 31.

• 19th Street multimodal improvements: Work will continue to install curb/gutter, sidewalks and buffered bike lanes. 19th will be reduced to one lane with flaggers where work is occurring, until May 30.

• 19th Street and Fourmile Canyon Creek Underpass: Crews will begin replacing the bridge over Fourmile Canyon Creek and construct a bike/pedestrian underpass. Northbound RTD 204 bus stops at Riverside and Upland will be temporarily closed. Work is anticipated to end March 2, 2026.

• 28th and Colorado protected intersection: This project is to install a protected intersection, sidewalk-level protected bike lanes and bus lanes. There will be lane closures where work is occurring, as needed. Expect delays, pedestrian and bike detours when traveling in the area. Work is expected to be completed June 30.

• 63rd waterline replacement: Both lanes of traffic on 63rd Street between Gunbarrel Avenue to the 63rd Street railroad crossing will shift to the east side of 63rd Street. Work hours are 7 a.m.-5 p.m. Monday-Friday and is expected to be completed by June 29.

• 11th Street and Canyon Boulevard stormwater improvements: This is a city led project resolving a utility conflict between the storm sewer and sanitary sewer. Westbound lanes on Canyon Boulevard from Broadway to Ninth Street will be closed. Work will take place through May 31.

• Sixth Street bridge maintenance: Structural repairs on the surface and beneath the bridge, waterproofing, HMA overlay, tree trimming will take place on Sixth Street bridge. Full road closure during surface work and path closure during work beneath the bridge will occur. Work will take place from 8 a.m.-5 p.m. through June 4.

• 30th Street corridor multimodal improvements project: This project will improve 30th Street between Colorado and Arapahoe avenues. The improvements include adding protected bike lanes, wider sidewalks and new landscaping for safer, more comfortable and more convenient travel experience. Travelers can expect periodic delays and flaggers guiding traffic, impacts to the vehicle lanes with single lane closures as needed, RTD Bound stop impacts and detours for people walking and biking.

Boulder County

• Colo. 119 safety, mobility and bikeway construction: CDOT will begin work on Colo. 119/Diagonal Highway. This project is anticipated to be completed in spring 2027.

Frederick

• County Road 5 closure: Claystone Construction is installing a new sanitary sewer main to connect Erie’s Summerfield subdivision to the Erie North Water Reclamation Facility northeast of Highway 52 and East County Line Road. The road closure is WCR 5, between Colo. 52 and WCR 16.5. County Road 3.25 and County Road 7 (Aggregate Blvd.) north of Highway 52 will remain open as detour routes. Work will last until the end of May.

• Waterline installation: Thalle Construction is installing a 42-inch waterline as part of the Thornton Water Project. The waterline will pass through two miles of the Frederick Planning Area. The pipeline will be installed at a depth of at least 4 1/2 feet, with crossings under WCR 14 and WCR 16 at 6 feet deep. To install the pipeline, planned 72-hour road closures will be necessary WCR 14 in mid-March, WCR 17 in mid-June and WCR 16 in early July.

Erie

• WCR 7 waterline improvements: The town of Erie is working on the WCR 7 Waterline Improvements project. This project will install a new transmission waterline to secure the future delivery of potable water, impacting approximately 2.7 miles of WCR 7 and requiring significant traffic changes. Expect full closures between WCR 12 and Colo. 52, and single-lane traffic south to Erie Parkway through August.

• Lane closure and flagger operations on County Line Road: Duran Construction will return to County Line Road to complete final punch list items and install landscaping and irrigation. Work will occur between Cheesman Street and Telleen Avenue and is expected to continue through Friday, weather permitting. One northbound lane will be closed between intersections as work progresses. Flagger operations will be in place to manage traffic safely through the area. Per the project specifications, lane closures in front of the school — between Moffatt and Cheesman — will be limited to 9 a.m.-3 p.m. to avoid school pick-up and drop-off congestion. In the remainder of the work zone, lane closures may occur from 9 a.m.-4 p.m. Work will begin on the north end of the corridor, just south of Cheesman Street.

• County Line Road irrigation tap installation: On Saturday, crews will be working near the elementary school on County Line Road to install an irrigation tap. Work will begin at 7 a.m. and is expected to be completed, including paving, by 7 p.m. The northbound lane of County Line Road will be closed between Moffat Street and Cheesman Street throughout the day.