Trip reduction ordinances

Trip reduction ordinances include different types of regulations or measures to help mitigate congestion. Typically, there are three forms: restrictions or requirements for developers, employer trip reduction programs, and/or forming transportation management districts and associations.

Key characteristics





WSDOT regions

Strategy description

City, state, and local agencies use trip reduction ordinances to encourage different travel choices by mandating investments, offering incentives, or setting goals for reducing drive-alone trips. Developers, transportation agencies, and employers have different, but critical, roles to play in planning and implementing trip reduction strategies.

Development and construction projects

Before permitting land use or rezoning a parcel of land, cities may provide incentives to developers who meet congestion mitigation requirements. Rules and regulations on new developments may require developers to provide sufficient ridesharing or public transit facilities (e.g., including a bus station with convenient access) before construction is allowed.

To reduce the traffic impact of their projects, developers can include trip reduction strategies in their state- and federally-mandated traffic impact analysis (TIA) reports.

Businesses and employers

Businesses and large employers are prime candidates for trip reduction ordinances as they contribute to high levels of travel during peak commuting times. Because even small reductions in trips during peak travel times can reduce congestion, the most benefit comes from pairing trip reduction ordinances with incentive programs.

Washington State’s Commute Trip Reduction (CTR) Law requires businesses with over 100 employees in congested regions to reduce drive-alone commute trips (1). Employers must develop and manage trip reduction programs based on locally adopted goals for reducing vehicle trips and miles traveled.

Employers may also provide employee incentives, such as flexible schedules or compensation for alternative travel choices. They can also promote ridesharing, transit, alternate modes and routes, and/or shift the time that employees are expected to travel.

Transportation agencies

Transportation management districts or associations (similar to a homeowners association) encourage the use of trip reduction ordinances by promoting the benefits or encouraging/enforcing various programs. For example, WSDOT’s CTR program provides technical assistance to jurisdictions and employers to help them set up and monitor trip reduction programs (2).

When to use this strategy

Trip reduction ordinances make sense for regions with serious congestion or pollution issues, where drive-alone trips are a significant contributor to congestion. Ordinances are best targeted at large employers and major activity centers (e.g., stadiums, convention centers) that draw significant crowds of people.

Strategy benefits:

  • Reduced congestion by reducing the amount of vehicles on the road during commute times
  • Improved travel reliability for road users as a result of reduced congestion
  • Environmental improvements resulting from reduced traffic volume, reduced congestion, and increased active transportation of walking and bicycling
  • Relatively low cost (when compared to other mitigation strategies)
  • Increased use of alternative travel modes like transit, bicycling, or carpooling

What you need in order to implement

Policy needs:

  • Determining whether measures should be compulsory or voluntary, and what the appropriate methods of enforcement should be for employers and developers that do not comply

Planning needs:

  • Technical support programs to assist developers, businesses, and local agencies in implementing ordinances
  • Baseline understanding of existing employee commute behavior and the availability of alternatives (typically gained through surveys)
  • Methods for collecting data on travel patterns, mode sharing, and other metrics to evaluate the effectiveness of trip reduction ordinances

Agency resources needs:

  • Agency staff to oversee the program, work with employers, develop programs, and write, revise, and interpret related policies

Learn more about this strategy

USDOT’s Commuter Choice Primer: An Employer's Guide to Implementing Effective Commuter Choice Programs

Works cited:

(1) Washington State Revised Code, RCW 70.94.531, Transportation demand management - Requirements for employers

(2) WSDOT Commute Trip Reduction (CTR) program website.

About key characteristics

Location notes:

Trip reduction ordinances are most applicable for urbanized areas that experience congestion during the morning and evening peaks, as well as metropolitan suburban areas where much of the drive-alone trips originate.

Cost notes:

Trip reduction ordinance costs are low when compared to other congestion mitigation strategies. The main costs are related to program administration, enforcement, and assistance as required by businesses and local governments.

Technology notes:

Some trip reduction strategies may include technology, like employee ridematching applications, but for the most part technology needs for trip reduction ordinances are low.

Collaboration notes:

Agencies, employers, chambers of commerce, trade organizations, and employees should collaborate to identify reasonable trip reduction goals, appropriate strategies, and effective incentives as part of a comprehensive trip reduction ordinance.