Parking and Transportation Demand Management Ordinance

Long shadow of bikes parked at Cambridge Main Library
Passengers sitting on an EZRide shuttle bus

The PTDM Ordinance is a national model for improving mobility and access, reducing congestion and air pollution, and increasing safety by promoting walking, bicycling, public transit, and other sustainable modes. The ordinance was adopted in 1998 and made permanent in 2006.

Participation is triggered when an owner of non-residential property proposes to add parking above the registered number. All projects subject to the PTDM Ordinance must have an approved PTDM plan before they can obtain all permits, including Special Permit, building permit, occupancy permit, etc.

Does the PTDM Ordinance Apply to Your Project?

To check the number of registered parking spaces on your parcel and determine whether your project requires PTDM approval, please contact Adam Shulman in the Traffic, Parking and Transportation Department at 617/349-4745,

How to Register Parking

Register parking spaces in the City of Cambridge, including commercial, non-commercial, and residential. Submit form to the Department of Traffic, Parking and Transportation:

Interdepartmental Parking Facility Registration Form

Large Project PTDM Plan

Total parking = 20 or more spaces

Plan requires:

  • Single-occupancy vehicle mode-share commitment
  • Comprehensive set of transportation demand management (TDM) measures
  • Annual monitoring and reporting
  1. Employee, visitor, and/or patron survey, including SOV rate
  2. Biennial counts of car and bike parking occupancy and driveway ins/outs
  3. Status of required TDM measures

A Large Project PTDM Plan requires the proponent to set a maximum mode-split commitment for single occupancy vehicles (SOV). SOV commitment is based on either similar project's traffic impact study assumption, ten percent reduction below 1990 US Census Journey to Work data, or baseline survey, depending on PTDM Officer determination. 

Determine the census tract for a specific address

Look up the 1990 SOV mode split for a specific census tract, including map

Small Project PTDM Plan

Total parking = 5 to 19 spaces

Plan requires:

How to Create a PTDM Plan

  1. Property owner submits Draft PTDM Plan
  2. PTDM Officer issues draft finding with comments and guidance for revisions
  3. Property owner submits Final PTDM Plan
  4. PTDM Officer issues final decision--Approved, approved with conditions, or denied

PTDM Officer has 60 days to issue a decision from the date of draft submission.

Helpful Resources for Submitting a PTDM Plan

Detailed instructions on how to write a PTDM plan

City of Cambridge Bicycle Parking Guidelines

Sample PTDM plan

Sample bicycle parking plan

PTDM Employee Transportation Coordinator Designation Form 

Complete when property subject to the PTDM Ordinance is transferred to new ownership:

PTDM Plan Property Transfer Form

Sample TDM measures

  • Transit subsidy
  • Pre-tax transit benefit
  • Free shuttle bus
  • Market-rate parking fee charged directly to employees or patrons
  • Daily parking charge available for occasional drivers instead of monthly parking pass
  • Financial incentive for walking or biking
  • Bicycle tools and air pump on-site
  • Showers/lockers on-site
  • Bluebikes station funds
  • Bluebikes membership
  • Emergency ride home program
  • Car/vanpool matching program
  • Priority/discounted HOV parking
  • Transportation information or real-time transportation information screen
  • TMA membership (Charles River TMA or Alewife TMA)
  • Hire Cambridge residents
  • On-site TDM coordinator
  • Provide bus shelter

Annual Reporting

Click here for the training course on how to submit your annual report using our online system.

Sample PTDM Annual Monitoring Report

Transportation Monitoring Program Results

Click here for the 2023 TDM Program Report

Click here for the fall 2022 PTDM Report

Click here for the 2018 PTDM Report

Click here for a video of the 2018 PTDM Report presentation at the 12/3/19 Transportation & Public Utilities Committee Meeting

Click here for the 2011 PTDM Report

Full Text of the Parking and Transportation Demand Management (PTDM) Ordinance

The citation is Cambridge Municipal Code Chapter 10.18 - Parking and Transportation Demand Management Planning, Parking Space Registration.

Click here for the full text of the Ordinance.

Full Text of the Vehicle Trip Reduction (VTRO) Ordinance

The citation is Cambridge Municipal Code Chapter 10.17 - Vehicle Trip Reduction Ordinance.

Click here for the full text of the Ordinance.

A bicylist and pedestrians move down Main Street past MIT's Stata Center in Kendall Square



Car-free Commuting Push Pays Off in Kendall Square 

For More Information

For more information, contact the City's PTDM Planning Officer Stephanie Groll at either 617/349-4673 or