Tysons Corner Consolidated Transportation Impact Analyses (CTIAs) BOS Transportation Committee May 8, 2012

Tysons Purpose of CTIAs Analyze impact of pipeline developments. Individual impact studies (TIAs) do not consider pipeline developments Analyze 2030 and 2050 levels of development for the analysis area and determine associated mitigation measures Finalize grid of streets including Functional classification Number of lanes between and at intersections Accommodation of transit, bikes, and pedestrians Right-of-way needs Create a Tysons-wide simulation model Bullet 1 – the necessary adjustments would provide an acceptable level of traffic flow, be cost effective, and identify the minimum ROW required with the least negative impacts to adjacent properties and the environment by taking into consideration the provisions of the Tysons comprehensive plan Bullet 2 – Three levels of development are being tested – 1. Plan Buildout including Rezonings, 2. Rezonings with existing development, and 2030 GMU Forecast

Tysons East is used as an example Macroscopic Models – Regional Transportation Model Public policy, regionally significance projects Mesoscopic Models – Sub Area Extractions Link regional trip purpose to details of micro-simulation models Microscopic Models – Street Traffic analysis “Visualization” of solutions, detailed intersection operations analysis Tysons East is used as an example

MWCOG Regional Model This is an overview of the entire MWCOG model. The entire model is heavily concentrated in the Metro Washington area which includes a great level of detail in Fairfax County. The red polygon shoes the full extent of the VISUM model while the smaller red polygon represents the Tysons East study area.

Tysons East Analysis Area -This image is of the Tysons East CTIA Analysis Area. -The CTIA analysis area is defined as a coherent area of Tysons where rezoning activity is prevalent and where the traffic impact of the rezoning activity is significant. It is also typically a sub-district as defined in the Tysons Comprehensive Plan with adjustments resulting from taking into consideration traffic impact and the grid of streets. Gateways providing access and egress to and from the analysis area will be included in the analysis.

Tysons Central Analysis Area -Like the last image, this is the Tysons Central Analysis Area

Tysons West Analysis Area -Finally, this is the Tysons West Analysis Area

Volume/Capacity Sample Output -This map shows a sample result, output by the model of a Volume-to-capacity ratio map. (Explain how these are used and how we are coordinating this data with the developers and their consultants for review.)

Measures of Effectiveness (MOE) Level of Service and Delay at Intersections Vehicles Mile Travel Hours of Delay Average Speed Travel Time Queue Length

CTIA Process with Stakeholders Weekly meetings Inclusive, collaborative process Full access to information Analyze suggestions from stakeholders Many iterations of testing alternative mitigation measures – what transportation measures are required to accommodate proposed land use intensity levels? Focus is cost-effectiveness

CTIA Analysis Process – Tiered Approach No right of way impact (traffic reassignment, signal modification, lane restriping) Some right of way impact (turn lanes, additional through lane, additional grid link) Additional mitigation -Mention use of CDPs -describe large scale mitigations. -used in conjunction with lesser mitigations (ex: lane config changes depending on what large scale mitigation used)

TIER 2 – ROW Impacts

TIER 2 – ROW Impacts

TIER 3 – Additional Mitigation

I-495 Dolley Madison

Conclusions (Tysons East) Traffic impacts were mitigated Identified right-of-way needs Finalized grid of streets Next Steps Submit analysis to VDOT to meet VA traffic impact study requirements Plan amendment