Florida DOT hits milestone in context-based street design

By Chris McCahill and Rayla Bellis

As part of its Complete Streets Implementation, the Florida Department of Transportation (FDOT) recently adopted eight context classifications to guide road design decisions. Under this new system, planners and engineers will consider existing and future characteristics such as land uses, building configuration, and street connectivity to ensure that roads are designed for the right vehicle speeds, road users, and trip types.

This new approach acknowledges that state roads often serve important local needs, such as when they run through town centers. According to FDOT, “the context classification provides an important layer of information that complements functional classification in determining the transportation demand characteristics along a roadway, including typical users, trip length, and vehicular travel speeds.” These classifications help determine whether an arterial roadway might need accommodations for pedestrians, bicycles, and transit users and whether it should have on-street parking, for example.

FDOT’s State Complete Streets Program Manager Dewayne Carver notes that “FDOT’s Complete Streets policy created a need to define context in a new way. After starting with the ITE/ CNU context zones, FDOT adopted a refined version of the draft AASHTO classifications, once those became available. The Department recognized early in our program that to provide ‘the right street in the right place’ we needed a more specific description of land use context.”

The approach is based partly on NCHRP Report 855: An Expanded Functional Classification System for Highways and Streets and mirrors documents like the Institute of Transportation Engineers’ Designing Walkable Urban Thoroughfares and Los Angeles County’s Model Design Manual for Living Streets. The Smart Transportation Guidebook, produced by the Pennsylvania and New Jersey Departments of Transportation in 2008, also describes similar context zones.

While the concept is not new, Florida is among the first states to incorporate it into formal decision-making processes. The classifications, which include “rural town,” “suburban commercial,” and “urban core,” will apply in design decisions for new or modified roads by determining allowable design speeds, lane widths, and other design controls and geometrics within the new draft Florida Design Manual.

The classifications will also eventually be used in FDOT’s Quality/Level of Service Handbook, while FHWA’s more general classifications of “urban” and “rural” will still apply in funding considerations.

Florida’s approach may provide a model other states can use to consider land use context in decision making. FDOT’s recently released context classification guidance provides fairly detailed methodologies for identifying context and determining user needs and travel demand for each mode. Washington State has also recently adopted a similar approch that could serve as a model for others, incorporating context classification into the current WSDOT Design Manual as part of the department’s Practical Design initiative.

Chris McCahill is an Associate Researcher at SSTI. Rayla Bellis is a Program Manager at SSTI.