California Department of Transportation

Tradeoffs Between Person Throughput and (Level of Service) LOS Degradation When Mixed Flow Lanes are Converted to Bus Only Lanes


Fouad Ziaullah

Task Description

The Department’s engineers do not have the experience or tools to adequately assess the feasibility of proposed BRT projects when they require converting an existing travel lane on a conventional highway into a dedicated BRT lane.  Also, Caltrans design guidance states that we cannot approve a project that decreases LOS.  Any project that converts a mixed-flow lane to a bus-only lane will decrease LOS by some degree, which means we cannot approve these projects in any situation.  To honestly implement the BRT in Director’s Policy 27 or the soon to be approved Deputy Directive 98, we need to establish guidelines on how much LOS degradation is allowed for an increase in person throughput.

Task Objective

The objective of the proposed research is to identify and evaluate the impacts associated with implementing bus rapid transit in a bus-only running way setting on a conventional highway, and to determine under what conditions a BRT-related project may be implemented on a conventional highway.

Final Report/Deliverables

Assess the Trade-Offs between People Throughput and Level of Service Degradation in the Conversion of a Mixed Flow Lane to a Bus Only Lane on US 101