Intersection Buffers 

Image Source: Google Earth – MN 95, Minnesota

DEFINITION AND DESCRIPTION

Intersection buffer treatments can be applied at rural, high-speed intersections with side-street stop control. They narrow the mainline approach intersections by adding a striped buffer area that includes centerline rumble strips. This narrowing is intended to encourage drivers to reduce speed as they approach the intersection. The striped buffer area also enhances separation between opposing traffic and increases the visibility of the intersection.  Following installations in Minnesota, fatal and injury collisions decreased by 22% (Moreland et al., 2024).

Implementation Categories

CONSIDERATIONS

• At intersections with left-turn lanes, the buffer should be placed between the through lane and the left-turn lane to provide a positive offset.
• The maximum through lane width at the intersection is 10 ft. This application is not appropriate for roadways with lane widths less than 11 ft.
• See MUTCD Part 3 – Markings for information on pavement markings.
• If noise from the rumble strips are a concern, consider sinusoidal rumble strips. Details for these applications are on HSIP’s Project Development Resources website.

APPLICATION

• May be applied at rural, two-lane undivided, side-street, stop-controlled intersections.
• When turn lanes are not present begin the taper to narrow the lane approximately 300 ft prior to the intersection. The taper rate should be 1:posted speed.
• When turn lanes are present, the lane width taper should begin at the start of the turn-lane taper. Turn-lane widths are not reduced.
• The buffer is typically 4 ft, but may be 2 ft if existing through lane widths are narrower than 12 ft.
• Lane widths are typically narrowed to 10 ft.
• Rumble strips are applied on the approach side of the buffer and between the through and turning lanes.
• Can be included in resurfacing projects.

example

Image Source: Minnesota DOT