Committee reviews Lone Tree/Butler corridor designs, advances school and bike‑safety ideas

Carlton, a staff member leading the presentation, told the committee the Lone Tree Road/Butler corridor work remains in active design and that traffic control on-site currently provides one lane in each direction while the eastern half remains closed for construction. He said a planned overpass cross‑section includes separated pedestrian and bikeway facilities and that modeling shows a steep redistribution of traffic around the new facility: "A 70% reduction of traffic is expected on Beaver in San Francisco," Carlton said, describing the model that drops a nearby link from about 10,000 daily vehicles to roughly 1,100 in the scenario presented.

Why it matters: The proposed overpass and associated changes aim to shift through‑traffic off neighborhood streets and add protected space for people walking and biking. Committee members pressed Carlton for specifics about where traffic will increase, particularly south of Butler, and for the underlying assumptions that generated the long‑range model estimates.

Staff walked the committee through earlier design iterations and the tradeoffs that shaped the current proposal: dual left‑turn lanes remain to handle congestion, while channelized right‑turn lanes were removed to shorten pedestrian crossing distances. Carlton told the group ADOT would not permit Butler intersection traffic to spill onto Route 66, a constraint that precluded some previously considered options.

The presentation placed a priority on separated bikeways because of safety benefits. Carlton cited an expected crash‑reduction effect of "up to 25%" for separated facilities versus on‑street bike lanes. Commissioners and attendees discussed transitions where separated paths reconnect to street lanes and where driveways might create conflicts.

Safe Routes to School was a central focus. Staff said a grant is funding the design work around Nolles and Sawa schools, with options that include curb‑level bikeways, raised sidewalks, widened parkways and two‑way off‑street paths in constrained locations. The committee debated whether certain short sections should be striped as one‑way bikeways or left unmarked to function as two‑way paths; one member noted user demand for two‑way use during school peak times and suggested removing stencils in tight segments to allow two‑way flow.

Participants flagged site constraints that affect crossing design. Carlton supplied slope figures used in the analysis — about 4% in one segment and more than 5% in another — and explained that steep grades can limit full‑stop control options, pushing the design team toward rapid‑flashing beacons and median refuges in some midblock locations. The group also discussed a nearby fire station driveway whose grade and profile complicate typical curb or ramp solutions.

The discussion extended into neighborhood corridors such as Cedar, where committee members explored road‑diet options, added street parking for traffic calming, and possible roundabouts at major nodes. Staff said striping upgrades and added green conflict markings on bike lanes could arrive in the near term on selected blocks.

What’s next: Staff said more detailed drawings and 60% plans for Butler and related intersections will be available at future meetings and that the team will continue outreach with schools, Mountain Line and property owners to refine crossing locations, bus‑stop placements and bike alignments. The committee lost quorum and adjourned before votes on further actions.

Ending: The committee asked staff for follow‑ups on modeling inputs, exact roadway cross‑sections at the southern end of Butler, and proposed crosswalk locations near bus stops; staff agreed to return with more detailed plans at the next session.