Fairfax County
Determining Multifamily Residential Development Parking Demand and Trip Generation in
Urbanizing Suburban Activity Centers; Lets Not Overpark
Provide a brief project description (1-3 sentences):
As the line between urban and suburban areas of Fairfax County have blurred, it has become
increasingly difficult to plan necessary parking supplies, and to understand the number of trips
generated, for and by multi-family residential developments in our urbanizing suburban activity
centers. This study would analyze parking demand and trip generation at 10 multi-family
developments around Fairfax County, broken down into the following three categories: 1-Sites
located within 1/4 mile of Metrorail, 2-Sites located within 1/4 mile of 2 or more bus transit
routes, and 3-Sites located within 1/4 mile of 1 or no bus transit routes. The results of this
analysis will help Fairfax County update the zoning ordinance with regards to parking
requirements for multi-family residential developments, likely reducing the construction of
unnecessary parking, as well as better understand the number of trips generated by these
developments to better mitigate their impacts.
Describe the final product that will result from this project (1-2 sentences):
The final product that will result from this project will be a technical report, summarizing the
findings of the study, along with recommendations to adjust parking requirements and
anticipated trip generation rates for multi-family residential developments in Fairfax County.
Explain what linkages the project creates between agencies or jurisdictions (1-2 sentences):
Internal to Fairfax County, a reduction in parking ratios and a better understand of trip generation
creates a linkage between agencies involved in the development and enforcement of parking
supplies and projects to mitigate traffic impacts, namely the Fairfax County Department of
Transportation, the Fairfax County Department of Planning and Zoning and the Fairfax County
Department of Public Works and Environmental Services among others. The difficulty in
determining an appropriate parking supply, and to understand trip generation, for and by multifamily residential developments in urbanizing suburban activity centers is a problem that’s
experienced in comparably urbanizing suburban communities in the DC Metro region, namely
Montgomery County and Prince George’s County in Maryland. It is anticipated that this project
will create similar internal linkages within these jurisdictions as well.
Explain how the project will yield clearly defined implementation and funding priorities or next
steps (1-2 sentences):
The project will provide recommendations to adjust parking requirements for multi-family
residential developments in Fairfax County that can directly be used as a basis to update the
Fairfax County Zoning Ordinance with regards to parking requirements. The project will also
produce trip generation rates that are specific to multi-family residential developments in Fairfax
County. Once the study is complete, the next step would be to present the Final Report to the
Fairfax County Board of Supervisors so that its results can be immediately utilized to determine
necessary mitigation to address trips generated by proposed developments and redevelopments
of properties anticipated to contain multi-family residential uses.
Project Not Located in/near Activity Center/Metro Station. Jurisdiction-wide project
Project does not involve any of the 25 stations in the TCSP “Improving Pedestrian/Bicycle
Access as Select Rail Stations” study.
Explain what lessons-learned or models the project will provide for the region (1-3 sentences):
As previously stated, Montgomery County and Prince George’s Counties, in Maryland, face
these same challenges, with projects like the Pike & Rose development in Rockville, the Crown
Development in Gaithersburg, or the Riverdale Park Station development in Riverdale. The Final
Report created through this study can be utilized by these adjacent jurisdictions to adjust their
own parking requirements and trip generation assumptions for comparably located multi-family
residential developments, reducing the unnecessary construction of parking and roadways on a
regional level.
Explain how the project will support the future enhancement of the local transportation and
land-use context. (1-3 sentences):
The anticipated recommendation of this study, for a reduction in parking requirements for multifamily residential development, is likely to have a positive impact on the cost to construct multifamily residential developments in Fairfax County, further encouraging this land use type. Multifamily housing is a compact development pattern that limits environmental impacts, strengthens
the desirability and demand for alternative modes of transportation and more efficiently utilizes
transportation infrastructure than other types of residential development patterns. Further, the
results of the study are also anticipated to show that multi-family residential developments in
Fairfax County produce fewer trips than standard ITE trip generation rates might suggest, which
will reduce the over engineering and construction of unnecessary transportation improvements
and allow a more efficient use of existing infrastructure.