Based upon the Transportation Impact Study submitted by the developer, daily Saturday traffic will increase from 980 trips to 13,773 trips to/from the AT&T site! (page 68). That is a 1305% increase of trips generated!

Weekday traffic will also increase by 173% from the AT&T site with an increase to 11,573 vehicles entering or leaving the AT&T site. An estimate of 700-900 more cars per hour during normal waking hours on Chain Bridge Corridor.

The developer is required to use a standard trip generation database for calculating trips. However, Fairfax County allowed the developer to reduce the estimated number of trips for the development’s residents by 25%. This reduction incentive is called a Transportation Demand Management (TDM) Incentive. Based upon the Transportation Study, the developer is planning to publish bus schedules, improve pedestrian walkways, provide bike parking and provide on-site parking spaces for car sharing to receive this 25% reduction.

In addition to the TDM 25% reduction, the developer is allowed to deduct for trips that do not use the current road system (Internal Capture) as well as trips that stop by the commercial retail and then head to another location. (Pass-by Reduction). 

As an example, stopping by the AT&T’s site grocery store before going to a friend’s house for dinner is a pass-by reduction. Even though this trip uses the Chain Bridge corridor, it is excluded from the count! 

A total of 5,372 trips are reduced from 19,145 calculated trips by the above factors.

If the developer built according to the current Comprehensive Plan, he would be able to build 635 dwellings including 106 affordable housing units versus 854 dwellings plus a shopping center.

The 635 dwellings would generate less trips than the proposed development.

Is another coffee shop or small grocery store worth a 1305% increase in Saturday traffic along Chain Bridge?

Fairfax VDOT is currently reviewing this study. Let them know what you think by signing the petition (no need to contribute) and forwarding to your neighbors https://chng.it/5LkX6xGxsv .