UW Analysis Projects at Least 2 Billion Extra Dark School Commutes Under Permanent DST
Permanent DST would impose billions of darker school commutes and elevate morning pedestrian risk according to geospatial modeling published in Current Biology. The change also removes the strongest circadian cue for children already facing early start times, an effect unevenly distributed by geography and district policy. Senate inaction leaves the policy outcome unresolved through at least 2025.
The Sunshine Protection Act passed the House in summer 2024 and has pre-approval in 19 states, yet remains stalled in the Senate. University of Washington biologists used actual school start times, enrollment figures, and geospatial coordinates for 14 pre-approving states to quantify morning darkness under year-round DST versus the current biannual switch. Extrapolation to the full country yielded the two-billion-trip figure, concentrated in western time-zone edges and districts with starts before 8 a.m.
Traffic-safety data showed fatal school-age pedestrian collisions were approximately twice as likely before sunrise. The study also highlights circadian disruption: morning light is the primary zeitgeber for adolescents whose delayed sleep phase already conflicts with early bells, potentially worsening sleep debt, mood, and metabolic regulation. Prior observational work links chronic morning darkness to higher rates of seasonal affective symptoms and reduced physical activity before school.
Equity effects are pronounced; lower-income districts more often schedule early starts and lack after-school daylight buffers. The bill’s Senate prospects hinge on competing priorities in the lame-duck session and renewed state-level pressure after the 2024 elections.
Senate: The Sunshine Protection Act receives no floor vote before December 2025.
Sources (2)
- [1]Primary Source(https://www.cell.com/current-biology/fulltext/S0960-9822(24)01345-6)
- [2]Supporting Source(https://jamanetwork.com/journals/jamapediatrics/fullarticle/2791234)