RTD Lifts Final Light Rail Speed Restrictions

PAULINE HABERMAN
Project Manager, Special Projects
Denver Regional Transportation District (RTD), CO

Denver RTD has lifted all 31 light rail speed restrictions put into place last year as the agency implemented more rigorous inspections for our more than 120 miles of light rail track.

Track Maintenance Work and Repairs

Inspections began last May as RTD intensified its focus on maintaining its assets in a state of good repair and found several minor issues and track imperfections along isolated sections of the light rail network. Until preventative maintenance work could be completed, 10 mile-per-hour speed restrictions were implemented across four separate slow zones. A team of nearly 100 RTD staff worked in three shifts to safely complete the repairs.

Since last June, RTD crews have removed and replaced 12,091 feet of track, or a distance over two miles. The work primarily occurred during overnight maintenance windows and required crews to power down the system’s overhead wires. The work also involved carefully transporting and staging new sections of track for installation.

Over nine months, more than 50 miles of rail underwent grinding to remove surface defects, reducing the risk of cracks forming in the future. Crews also installed joint bars and leveled the ballast that provides stability and supports the light rail tracks. In total, RTD has replaced, lined, tamped, and surfaced more rail over the last year than during the previous 20 years combined.

RTD began extending overnight maintenance windows to maximize work being performed over consecutive days. This allowed us to plan for disruptions and provide bus shuttles to support impacted customers. Work completed during the overnight windows led to nine speed restrictions being lifted between January and March.

Track Inspections

RTD adheres to APTA standards for periodic inspection and maintenance of transit tracks. APTA’s standards include visual, electrical, and mechanical inspections of components that affect safe and reliable rail operations, as well as for implementing necessary speed restrictions.

RTD’s light rail inspections are conducted annually, quarterly, monthly, and twice weekly.

Once a year, RTD conducts an ultrasonic inspection of all 120 miles of light rail track, which uses high-frequency sound waves to detect internal flaws, cracks, or other structural issues. Staff also walk the entire system every 90 days to take additional measurements, identify recurring issues, and document any anomalies found.

Twice each week, a “hi-rail” vehicle drives the track at speeds where the rail can be carefully assessed.

Future Speed Restrictions

Due to RTD’s aging rail infrastructure, temporary speed restrictions will continue to be implemented in the future, when necessary, following regular track inspections. RTD’s light rail speed restrictions webpage is updated regularly to reflect any work underway that requires speed restrictions.