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.

Small Project PTDM Plan if total parking = 5 to 19 spaces.

Large Project PTDM Plan if total parking = 20 or more spaces.

Small Project PTDM Plan requires:

Large Project PTDM Plan requires:

  • Single Occupancy Vehicle mode-share commitment (Generally set at 10% below 1990 Census Data, our environmental baseline for PTDM projects)
  • Comprehensive set of transportation demand management (TDM) measures
  • Annual monitoring and reporting
    1. Employee and/or patron survey, including SOV rate
    2. Biennial counts of car and bike parking occupancy and driveway ins/outs
    3. Status of TDM measures

Full Text of the PTDM Ordinance

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

Click here for the full text of the Ordinance.

PTDM Results

Click here for the 2011 PTDM Annual Report.

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,

Why Do You Need to Comply with the Ordinance?

All projects subject to the PTDM Ordinance must have an approved PTDM plan before they can obtain the necessary permits.

How a PTDM Plan is Created

  1. Developer submits Draft PTDM Plan
  2. PTDM Officer issues draft decision with recommendations for revisions
  3. Developer 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 submittal.

Click here for detailed instructions on how to write a PTDM plan.

Click here for the City of Cambridge Bicycle Parking Guidelines.

Sample Plans & Reports

Click here for sample PTDM plan.

Click here for sample bicycle parking plan.

Click here for sample PTDM annual monitoring report.

Sample Surveys


Click here for the employee survey (weekdays).

Click here for the employee survey (one weekend day).

Click here for the employee data submission template.


Click here for the patron survey.

Click here for the patron data submission template.

College Students

Click here for the college student survey.

Click here for the college student data submission template (same as employee).

K-12 Students

Click here for the K-12 student survey.

Click here for the K-12 student data submission template.


Click here for the resident survey.

Click here for the resident data submission template.

Sample TDM measures

  • Transit subsidy
  • Free shuttle bus
  • Bus shelter
  • Market-rate parking fee charged directly to employees or patrons
  • Daily parking charge available for occasional drivers in stead of monthly parking pass
  • Bicycle parking above minimum zoning requirement
  • Shower/locker
  • Financial incentive for walking or biking
  • Emergency ride home
  • Car/vanpool matching
  • Priority/discounted HOV parking
  • Transportation information
  • Hiring of Cambridge residents
  • On-site TDM coordinator
  • TMA membership

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

PTDM-Related Census Links

A Large Project PTDM Plan requires the proponent to set a maximum mode-split commitment for single-occupancy vehicles (SOV), based on 1990 US Census Journey to Work data.

Determine the census tract for a specific address (coming soon)

Look up the 1990 SOV mode split for a specific census tract, including map (coming soon)

PTDM Ordinance Forms

Click here for the Interdepartmental Parking Facility Registration Form.

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

Click here for the PTDM Plan Property Transfer Form.

Must be completed when property subject to the PTDM Ordinance is transferred to new ownership.

Click here for the PTDM Small Project Form.

Submit a plan for a project that will have a total of 5 to 19 parking spaces.

Click here for a PTDM Employee Transportation Coordinator Designation Form.

Press Related to PTDM

 Car-free Commuting Push Pays Off in Kendall Square

Boston Globe Sunday Editorial on decreased traffic in Kendall Square.

For More Information

For more information contact PTDM Officer Stephanie Groll at either 617/349-4673 or