Chapter 16: Driveways
16.1 Overview
Driveways provide the physical transition between the public highway and the abutting property. Driveways should be located and designed to minimize negative impacts on traffic operations while providing safe entry and exit to/from the abutting property.
The location and design of the driveway should consider characteristics of the roadway, the abutting property, and the potential users. To ensure that driveways provide for safe and efficient traffic movements, it is necessary to consider the driveway's critical dimensions and design features.
This chapter applies to new driveways, and modification of existing driveways.
This chapter provides guidance on the location and geometric design of driveway connections intended to provide vehicular access to a highway on the State Highway System.
The guidance provided herein may not always be completely applicable due to the highly variable field conditions with respect to driveways.
Departures from this design guidance for driveways to meet field conditions do not require or constitute a need for any type of design exception or design waiver unless the driveway is defined as a public driveway (see
below).
However, departures from guidance may require support documentation in the form of traffic operations and safety analysis.
For additional information refer to TxDOT’s
for permitting guidelines and for additional access discussion. For additional information on when
may be considered at driveways refer to the
, Section 10.2.2.
16.1.1 Definitions
- Access Connection- Facility for entry and/or exit such as a driveway, street, road, or highway that connects to a highway on the State Highway System; as defined by .
- Commercial Driveway- An entrance to, or exit from, any commercial business, or similar type establishment.
- Divided Driveway- A driveway providing a median, between the ingress/egress sides of a driveway. Medians can be painted (fully traversable) when curbing is not allowed within the right-of-way (ROW), slightly raised curb (mountable) when U-turns are allowed or curbed (traversable) when U-turns are not allowed.
- Driveway Apron- Normally the distance from the roadway edge of pavement or face of curb and gutter to the back of taper/radius return.
- Effective Turning Radius- The minimum radius appropriate for turning from the right-hand travel lane on the approach street or driveway to the appropriate lane of the receiving street or driveway. This radius is determined by the selection of a design vehicle appropriate for the streets or driveway being designed and the lane on the receiving street or driveway into which that design vehicle will turn.Urban roadways with limited distance from the road to the ROW line may use lesser radii that fit within the State ROW.See and for additional discussion on effective turning radius.
- Farm/Ranch Driveway- A Private Driveway providing ingress/egress for vehicles and farm/ranch equipment associated with the operation of the farm/ranch. Such driveways may also serve the residence of persons living and working on the farm/ranch and the other associated buildings.
- Field Driveway- A limited-use Private Driveway providing occasional/infrequent ingress/egress for equipment used for the purpose of cultivating, planting and harvesting or maintenance of agricultural land, or by equipment used for ancillary mineral production.
- Non-simultaneous Two-Way Driveway- A driveway intended to accommodate both entering and exiting traffic but not at the same time. For example, if an exiting vehicle is present in the driveway, the entering vehicle must wait until the exiting vehicle has cleared the driveway.
- One-way Driveway- A driveway designed for either an ingress or egress maneuver but not both.
- Private Driveway- An entrance to or exit from a residential dwelling, farm, or ranch for the exclusive use and benefit of the permittee as defined by .
- Private Residential Driveway- A Private Driveway serving a residential dwelling with anticipated P design vehicle and less than 20 vehicles per day using the driveway. A Private Residential Driveway should be designed as a Commercial Driveway if the anticipated design vehicle is SU or larger, or more than 20 vehicles per day are anticipated to use the driveway. Refer to for information on the various design vehicle designations
- Public Driveway (Streets and Roads)- An approach from a publicly maintained street, road, or highway as defined by . See for design requirements of Public Driveways.
- Radial Return or Flared Taper Return- The physical transition connection between the driveway and the roadway. A Radial Return is a curved radius. On a curb and gutter section, a Flared Taper Return may be a drop-down curb (parallel to the roadway) or an angular return curb (chorded between roadway and driveway).The top of curb profile must be 10 percent or flatter.
- Service Driveway- A Commercial, Public, or Private Driveway for occasional or infrequent use by vehicles or equipment to service an oil or gas well, electric substation, water well, water treatment plant, sewage lift station, wastewater treatment plant, detention basin, water reservoir, emergency services, automated or remotely controlled pumping station, logging road, and other activities that may be identified by TxDOT.
- Simultaneous Two-Way Driveway- A driveway designed with a combination of return radius and throat width that allows a selected design vehicle to enter at the same time that another selected design vehicle is exiting the driveway.
- Throat Length- The distance parallel to the centerline of a driveway to the first on-site location at which a driver can make a right turn or a left turn, measured on roadways with curb and gutter, from the face of the curb, and on roadways without a curb and gutter, from the edge of the shoulder. Refer to .
- Throat Width- The driveway width measured at the end of the return radii. Refer to .