13.7.4 Future Year Models
13.7.4.1 Geometry
In developing a future year model, other planned projects are considered as they may impact traffic in the study area. If there are geometric changes to the study area determined from planned projects in TxDOT’s Project Tracker or the Unified Transportation Plan (UTP), implement those changes by following the development guidance used to develop the existing model. Planned multimodal improvements are also included unless otherwise agreed upon.
13.7.4.2 Forecasted Demand
Future traffic demand is used to analyze planned projects in the future year models. Further guidance on the process of traffic forecasting is provided in
Section 3.3
of this manual. Traffic volumes are projected and balanced for the new conditions under the future year models to reflect the changes. Traffic volumes, classification data, vehicle characteristics, and traffic patterns are examples of inputs that are modified based on forecasted demand.13.7.4.3 Debugging
Future year models are recommended to follow the same debugging process as outlined in
Section 13.4.8
. Use engineering judgement when debugging.13.7.4.4 Validation
Validation demands data, which does not exist for future year analyses. Nevertheless, parameters are updated when necessary. Signal timing and phasing are changed to accommodate demand and new geometry improvements. Driving behavior can only be adjusted in future conditions when roadway geometry or traffic control changes drastically. The HCM 7th Edition provides guidance on adjusting capacities to accommodate CAVs. Guidance on CAVs in the HCM 7th Edition can be found in various chapters. For information on modeling autonomous vehicles, refer to the respective microsimulation software user guide.