Work Zone Mobility and Safety Program
Photo collage: temporary lane closure, road marking installation, cone with mounted warning light, and drum separated work zones.
Office of Operations 21st Century Operations Using 21st Century Technologies

Best Practice

Main Guidebook > Find a Practice > Best Practice Categories > Project Development/Design

BEST PRACTICE:

E3−3: Access/Egress Practices in Work Zones

DESCRIPTION:

In a work zone, construction vehicles are entering, leaving, and sometimes crossing open travel lanes to deliver materials and equipment to job sites or perform other work−related activities. These actions bring sometimes slow−moving work vehicles into faster−moving traffic driving past a work zone, presenting a potential risk of collision between construction vehicles and motorists. To address these issues, States have developed construction vehicle access/egress policies and practices to promote safety for workers and motorists in work zones. Policies typically address how job sites will provide a safe means for work vehicles and equipment to enter and exit travel lanes and for delivery of construction materials to the work space. Practices for safe access/egress range from coordination meetings to design specifications for acceleration/deceleration lanes to the use of technology.

Many States have policies or guidelines that specify how access/egress should be addressed on projects. The Virginia Department of Transportation (VDOT) Work Area Protection Manual includes a section describing techniques that should be used in the field to promote safe access/egress in work zones, including the use of flashing lights on construction vehicles at night to increase their visibility to motorists. VDOT's Transportation Management Plan Requirements include a list of considerations for acceleration/deceleration lanes in work zones and state that access/egress points shall be considered and discussed in each project's Temporary Traffic Control Plan. Section 11 of Texas DOT's Work Zone Safety and Mobility Guidelines includes a list of strategies that work zone practitioners should consider when implementing work zone access/egress points. Maryland State Highway Administration's access/egress guidelines are included in its Book of Standards and Standard Specifications. These documents provide general information on where signage should be placed to alert motorists of construction vehicles entering the roadway, require that construction vehicle access/egress be in the same direction as the flow of traffic, and list additional strategies that practitioners could employ if necessary in specific work zones of concern.

In Virginia and several other States, project teams meet with the construction contractor's vehicle operators prior to construction to educate them on the correct areas and methods for entering and leaving the job site. Follow−up meetings are held as needed to reinforce key concepts, discuss issues, and inform drivers of modifications to the access/egress locations due to construction phasing or other changes.

While it is always preferable to provide adequate acceleration/deceleration space for work vehicles to enter/exit travel lanes smoothly, sometimes project site space limitations make this infeasible. For work zones that have limited visibility or limited acceleration/deceleration lanes, the Minnesota DOT (MnDOT) uses vehicle detection technology to identify when construction vehicles are beginning merge, deceleration, or crossing activities and then alerts motorists. The identification of a construction vehicle triggers a message on a changeable message sign (CMS) to inform motorists in the travel lane that a slow vehicle is about to enter, leave, or cross the road, enabling the motorist to make an informed decision to either slow down or move over to avoid the vehicle. MnDOT's Intelligent Work Zone Toolbox (http://www.dot.state.mn.us/trafficeng/workzone/iwz/MN−IWZToolbox.pdf) identifies when this type of motorist information system is appropriate, and specifies how to configure the signage for maximum visibility and comprehension.

Maryland and Texas use CMSs with general work zone guidance information, additional signing for motorists approaching access/egress points, and flaggers to assist with construction vehicles entering and exiting the roadway.

REASON(S) FOR ADOPTING:

Work zones are often areas of constrained access and capacity that have construction vehicles entering, leaving, and crossing active travel lanes, which presents potential safety and mobility concerns. Access/egress policies and practices help agencies and contractors better provide for safe and effective work zone entry/exit during design and construction.

PRIMARY BENEFIT(S):

Providing adequate access and egress points in a work zone enables work vehicles to safely enter and exit the travel lanes of a road. Providing design features such as an acceleration/deceleration lane allows work vehicles to adjust their speed outside the travel lanes, and alerting motorists to work vehicle movements, both can reduce the risk of crashes and congestion when work vehicles merge into traffic.

MOST APPLICABLE LOCATION(S)/PROJECT(S):

Providing adequate access and egress points in a work zone enables work vehicles to safely enter and exit the travel lanes of a road. Providing design features such as an acceleration/deceleration lane allows work vehicles to adjust their speed outside the travel lanes, and alerting motorists to work vehicle movements, both can reduce the risk of crashes and congestion when work vehicles merge into traffic.

STATE(S) WHERE USED:

Maryland, Minnesota, Texas, Virginia , Colorado

SOURCE/CONTACT(S):

KC Matthews, Colorado DOT
Phone: (303) 757−9543
E−mail: KC.Matthews@dot.state.co.us
Office of Operations