District Department of Transportation

Traffic Safety Investigations

Street in SE DC

The District Department of Transportation (DDOT) is committed to making our city’s streets safer for everyone while minimizing impacts to traffic operations. A combination of traffic control devices and traffic calming measures helps keep all users of the roadway safe. DDOT's Traffic Safety Investigations identify intersections and corridors of concern, analyze existing conditions, and provide a plan for safety mitigations.

A Traffic Safety Investigation is initiated when a resident, ANC, or other community member or organization raises traffic safety concerns within the public right-of-way. When a traffic safety concern is identified, DDOT’s Roadside Safety Branch of the Traffic Engineering and Signal Division will perform a Traffic Safety Investigation to evaluate the extent of the safety issue and determine if any action is needed.

The Traffic Safety Investigation (TSI) Dashboard tracks the process from start to finish. Many of the TSI requests are complex and require review, data collection, or other investigations. DDOT is tracking to make sure residents can see where their request is in the process.

Residents should complete a Traffic Safety Investigation Questionnaire to provide information about the reported issue. Additionally, residents are required to obtain a letter of support from their ANC Commissioner. A petition is not required. For more information about the Traffic Investigation process, please review the How to Request a Traffic Safety Investigation flyer. 

The Traffic Safety Investigation process takes approximately 130 days to complete. Once completed, DDOT will deliver the study results to the resident before closing out the request. If safety mitigation is necessary, DDOT will develop recommendations and work with the community to identify the most appropriate solution(s). If the proposed recommendations change existing traffic control and/or on-street parking, a Notice of Intent will be issued by DDOT, which includes a 30 business-day public comment period. The timeline for installation of improvements varies based on the safety mitigation identified.

Traffic Safety Investigation Instructions

You must follow all the steps in the instructions below. If DDOT does not receive the necessary information, your Traffic Safety Investigation request will be closed in 40 days. You will receive one reminder email before the request is closed.

1.      Complete the Traffic Safety Investigation Questionnaire (linked below)

2.      Receive endorsement from your local Advisory Neighborhood Commissioner (ANC) or Councilmember. An endorsement may be in the form of either a physical signature or email.

Need help finding this information? Visit the links below:

3.      Email completed questionnaire and endorsement to DDOT at [email protected]

·         In your form or email, reference the 311 Service Request number assigned to this Traffic Safety Investigation request

Please Note: This request will be closed without the endorsement of the ANC Commissioner or Councilmember.

Contact TTY: