Commission reviews traffic‑calming revisions and new sidewalk‑gap scoring; staff warns against speed humps on streets without sidewalks

At the May 20 meeting the Ann Arbor Transportation Commission received two linked staff updates: a revision to the neighborhood traffic‑calming program focused on accessibility for streets without sidewalks, and a proposed update to the sidewalk‑gap prioritization system (version 4.0) that reweights criteria to prioritize schools, transit access and equity.

Cynthia, the transportation engineer supporting the program, and Kalista, the city’s new transportation coordinator who said she will serve as project manager for the neighborhood traffic‑calming update, told the commission staff paused installations on some retrofit raised devices while they review accessibility concerns. "Speed humps are not accessible for all users and that when there's no sidewalk connections then vertical devices are not appropriate for that corridor," Cynthia said, explaining the program is shifting toward paint‑and‑post quick builds and other horizontal measures for streets that lack continuous sidewalks.

Staff described coordination with the city sidewalk‑gap program: sidewalk requests tied to traffic‑calming petitions on streets without sidewalks will receive higher priority points in the sidewalk scoring matrix. Kalista and Cynthia said the goal is to maintain accessibility for people who must travel in the street and to ensure retrofit calming does not inadvertently make routes unsafe or unusable for people with mobility challenges.

Nick presented the proposed sidewalk‑gap prioritization update (version 4.0). The automated GIS‑driven system was trimmed from nine to seven core criteria and reweighted. The highest weights in the proposed model go to proximity to schools and proximity to transit; other criteria include whether a gap lies on a Tier 1 or Tier 2 safety corridor, evidence of community support (petitions or desire lines), roadway classification and whether sidewalks exist on one or both sides, proximity to other attractors (parks, libraries, major commercial areas), and a transportation‑equity index drawn from the transportation plan. Each criterion scores up to 10 points and the combined weighted result drives the public dashboard used for CIP selection.

Commissioners focused questions on the equity weighting, whether the automated scoring accounts for construction cost or technical feasibility, and how sidewalk projects might be bundled with resurfacing or utility work to capture economies. Nick said cost and complex technical constraints (trees, drainage, slopes) are considered during project selection after the automated scoring runs; the scoring itself is designed to be objective and streamlined, with a recommended "set‑aside" human review to catch anomalies that the automated model ranks unusually high or where sidewalk construction is infeasible.

Commissioners also discussed the sidewalk millage (passed in 2020) and how to get more miles built per year; staff said pairing sidewalk builds with other planned projects, using millage funds strategically, and soliciting community petitions where there is neighborhood support are among the levers available.

Staff invited public feedback; two virtual office‑hours sessions were announced (May 26 noon and June 3 6:30 p.m.). The revised sidewalk prioritization will be rerun after commission feedback and then used to select projects for the next TIP and CIP cycles.