Littleton staff unveil eight-treatment traffic-calming toolbox; pilot results, accessibility and outreach flagged

Littleton transportation staff presented a draft neighborhood traffic-calming evaluation and an eight-treatment toolbox to the Transportation Mobility Board, describing design guidance, pilot projects and five example location designs intended to reduce speeds and improve pedestrian crossings.

The toolbox, presented by Kyle Morris, an engineer in the city's Transportation Group, recommends eight preferred traffic-calming treatments and accompanying design details. "This project is still ongoing," Morris told the board, "it's not finalized. This is our first real touch point. So, keep in mind, this is where we're at right now. Still work to be done." The effort is framed as part of the city's Safer Streets initiative and is designed primarily for local streets and neighborhood connectors.

The nut graf: staff said the toolbox seeks to provide standardized, deployable solutions to reduce travel speeds and improve crossings on Littleton's local streets. That includes both vertical deflection treatments (speed cushions and raised pedestrian crossings) and horizontal measures (curb extensions, chicanes, pinch points and diverters). Staff also emphasized quick-build pilots and the intent to align future installations with larger capital projects when possible.

Staff described the city's existing inventory and evaluation approach. The consultant team counted roughly 79 existing traffic-calming installations dating back to 1997 (staff summarized that as "over 80" to reflect recent pilot installations). The evaluation looked at relative speeds using Urban SDK phone-data metrics, targeted spot speed studies, physical condition and visibility, parking interactions and user compliance. Morris and staff said vertical elements in Littleton generally perform well; the evaluation recommended updating horizontal features to increase perceived restriction and produce greater speed reduction.

Morris and the consultant team laid out the eight preferred treatments and design guidance: speed cushions (with emergency-vehicle cutouts and delineator treatments where bike lanes exist), raised pedestrian crossings (noted as a combination of a speed table and an enhanced crossing), traffic circles (with larger inside radii to feel more like a roundabout), curb extensions and daylighting at crossings, chicanes and pinch points, pedestrian refuge islands, and diverters to reduce through traffic on neighborhood streets. Morris gave dimensions used in the draft: the speed cushion detail called for a 3-inch height profile; a raised crossing/raised intersection concept was described as about a 4-inch rise over 10 feet.

Board members and residents raised multiple concerns. Members asked for clearer before-and-after speed data from pilot installations; staff said speed studies for every existing calming feature are available in draft form and will be circulated. Several commissioners and commenters pressed the team on accessibility and maintenance: staff said design details will replace diagonal apex curb ramps with directional ramps and integrate RRFBs or pedestrian hybrid beacons when appropriate to improve sightlines and wheelchair accessibility. Staff acknowledged drainage and maintenance constraints as a limiting factor for some treatments (curb extensions in low-lying locations can create pooling without new storm infrastructure).

Several TMB members and residents questioned whether the evaluation had omitted local, commonly used measures. A resident and board member raised DIPs (depressed or dip-style treatments used in some Littleton locations) and recommended they be explicitly assessed; staff replied that dips perform as traffic calming in site-specific contexts but often require grading or drainage work that makes them less deployable across the city, which is why the toolbox focused on treatments that could be more readily applied as pilots and standard designs.

Staff said David Evans and Associates (DEA) is preparing five location designs using the toolbox as worked examples: Irving Street (Barrie to Bellevue), Haley Avenue (Princess to Windermere), Stern Parkway (Alati to Broadway) and trail crossing applications at Lee Gulch, Park Street and Windermere. Those designs are intended to show how the toolbox would be applied in real corridors and to provide templates for future project work.

Board members repeatedly urged a stronger communications strategy. Several members said residents want clear evidence about what pilot measures caused measured speed reductions and where temporary treatments were effective before the city adopts more permanent installations. Morris agreed: staff will finalize pilot speed results and circulate them to the board.

Ending: staff said the draft toolbox will be refined and that DEA's location designs and finalized speed data will be distributed to the board for follow-up. The board asked staff to prioritize public explanation of pilot outcomes and to include police, communications and school-district responsibilities in a Safer Streets outreach plan.