Objective

Today’s transportation professionals, with limited resources available to them, are challenged to meet the 

mobility needs of an increasing population. At many 

highway junctions, congestion continues to 

worsen, and drivers, pedestrians, and bicyclists 

experience increasing 

delays and heightened 

exposure to risk. Today’s 

traffic volumes and travel 

demands often lead to 

safety problems that are 

too complex for conventional intersection designs 

to properly handle. Consequently, more engineers 

are considering various 

innovative treatments as

they seek solutions to 

these complex problems. 

The corresponding technical report, Alternative 

Inter sections/Interchanges: Informational Report (AIIR) (FHWA-HRT-09-

060), covers four intersection designs and two 

interchange designs that 

offer substantial advantages over conventional 

at-grade intersections 

and grade-separated diamond interchanges. The 

AIIR provides information 

on each alternative treatment covering salient 

geometric design features, 

operational and safety issues, access management, costs, 

construction sequencing, environmental benefits, and 

applicability. This TechBrief summarizes information 

on one of these alternative intersection designs—the 

median U-turn (MUT) intersection (see figure 1).

Figure 1. MUT intersection treatment in a corridor in Michigan.

Research, Development, and Technology Turner-Fairbank Highway Research Center 300 Georgetown Pike, McLean, VA 22101-2296

www.tfhrc.gov

TECHBRIEF

FHWA Publication No.: FHWA-HRT-09-057

FHWA Contact: Joe Bared, HRDS-05, (202) 493-3314, joe.bared@dot.gov

This document is a technical summary of the Federal Highway Administration 

report, Alternative Intersections/Interchanges: Information Report (AIIR)

(FHWA-HRT-09-060).

Median U-Turn Intersection
2

Introduction

MUT intersections can be implemented as either full 

MUTs—where direct left turns from both the major and 

minor approaches are eliminated from the main intersection—or as partial MUTs—where direct left turns 

from only the major approaches are eliminated. On 

the major road, left turns are eliminated by requiring 

drivers to first travel straight through the at-grade main 

intersection and then execute their left turns by making U-turns at the median opening downstream of the 

intersection. They then must turn right when they reach 

the cross street. On the minor street, drivers who want 

to turn left onto the major road must turn right at the 

main intersection, execute a U-turn at a downstream 

median opening, and proceed straight through the main 

intersection. Figure 2 shows the geometric design of a 

full MUT, while figure 3 and figure 4 show the left-turn 

movements from major and minor roads for this design.

MUT intersections have been widely used in Michigan, 

particularly in the Detroit metropolitan area where many 

roadways were constructed with wide medians on wide 

right-of-ways. Partial implementations (keeping the cross 

street left turns at the main intersection) with similar 

concepts have appeared in Florida, New Mexico, and 

Louisiana. The MUT intersection typically is considered 

a part of a corridor treatment. The elimination of leftturning traffic from the main intersection as well as 

left-turn signal phases results in both operational and 

safety improvements for the MUT intersection design.

Geometric Design

The primary design elements of the MUT intersection 

(see figure 2) are as follows:

•	 One-way crossovers are placed in the median to 

accommodate left turns from the major road to 

the side streets and left turns from the minor road.

•	 Median width requirements of 40 to 70 ft are 

necessary to accommodate large trucks. Where 

medians are narrower, MUT intersections can still 

be constructed; however, loons must be added to 

accommodate truck turns.

•	 The appropriate spacing from the main intersection to a U-turn crossover is an important design 

Figure 2. Typical MUT intersection view with crossovers on mainline approaches. 150 200 First Street (102)

R 130

250

150

Main Road (301)

660 ‘ (± 100’) from the major intersection
3

decision. Although variation exists in practice, 

the American Association of State Highway and 

Transportation Officials recommends spacing from 

400 to 600 ft, while the Michigan Department of 

Transportation (MDOT) suggests 660 ft ±100 ft as 

the standard spacing.(2)

•	 Crossovers (and loons if needed) for U-turns may 

be one lane or two lanes wide depending on U-turn 

and opposing traffic volumes and the number of 

receiving lanes. 

•	 Turn bays leading into U-turn crossovers are 

typically at least 250 ft long to provide for adequate deceleration and storage. 

•	 As a safety measure, driveways should generally 

be prohibited in close proximity to the main 

intersection and also on the opposite side of the 

arterial from a median U-turn crossover to prevent 

wrong-way movements in the crossovers. 

•	 Pedestrian crosswalk locations at an MUT intersection are unchanged from where they would 

be at comparable conventional intersections; 

however, in an MUT intersection, pedestrians are 

exposed to fewer conflicts with vehicles and therefore are expected to be safer. The major street 

crossing can be made in one or two stages.

Traffic Signal Control

The main intersection in an MUT intersection design 

is almost always signalized. A few unsignalized MUT 

intersections exist in Michigan, but these are limited 

to intersections with low volume cross streets. The 

crossover at an MUT intersection may or may not be 

signalized. Agencies should use standard signal 

warrants and/or guidelines for protected left turns in 

making the decision about whether to install signal 

control at the crossovers. The signals at the main intersection and the crossovers in an MUT intersection design 

have only two signal phases because direct left-turning 

traffic at the main intersection is redirected to a U-turn. 

Much of the efficiency gained from installing MUT intersections stems from the two-phase signal operation.

Operational Performance

The traffic simulation software VISSIM was used to 

compare the operational performance of the MUT intersection to a conventional intersection. Two geometric 

cases were simulated under six sets of traffic volumes. 

The reduction in signal phases at the MUT intersection 

provided increases in vehicle throughput ranging from 

20 to 50 percent over the conventional intersection. 

While there is additional travel distance for those making 

left turns at an MUT intersection compared to a conventional intersection, the total network travel time savings 

at the MUT intersection usually outweighs the travel 

time from the additional distance traveled.

Safety Performance

An MUT intersection has 16 conflict points compared to 

32 in a conventional intersection. Studies performed by 

the MDOT and the University of Michigan show that total 

crash reductions ranging from 20 to 50 percent can be 

expected with this level of conflict reduction.(3–5) Moreover, 

head-on and angle crashes that have high probabilities 

of injury are lower for MUT intersections compared to 

conventional intersections.

Applicability

Candidate corridors for MUTs are medium to high speed 

four-lane divided highways. In rural areas, MUTs may be 

installed to address existing operational and safety needs 

and also anticipated needs when it is clear that the area 

may be developed into a more suburban setting. In existing suburban (and urban) settings, MUTs will result in 

immediate benefits in safety and operations, especially 

for through travelers on the major and minor streets. 

Figure 3. MUT left-turn movements from the major 

street.(1)

Figure 4. MUT left-turn movements from the minor 

street.(1)

Minor Street

Minor Street

Major Street Major Street
4

Researchers—This study was performed by Principal Investigators Warren Hughes and Ram Jagannathan. For 

more information about this research, contact Joe Bared, FHWA Project Manager, HRDS-05 at (202) 493-3314, 

joe.bared@dot.gov. 

Distribution—This TechBrief is being distributed according to a standard distribution. Direct distribution is 

being made to the Divisions and Resource Center.

Availability—This TechBrief may be obtained from the FHWA Product Distribution Center by e-mail to 

report.center@dot.gov, fax to (814) 239-2156, phone to (814) 239-1160, or online at http://www.tfhrc.gov/safety.

Key Words—Median U-turn, Alternative intersection, median U-turn intersection treatment (MUTIT), and MUT.

Notice—This document is disseminated under the sponsorship of the U.S. Department of Transportation in the 

interest of information exchange. The U.S. Government assumes no liability for the use of the information 

contained in this document. The U.S. Government does not endorse products or manufacturers. Trademarks or 

manufacturers’ names appear in this report only because they are considered essential to the objective of the 

document.

Quality Assurance Statement—The Federal Highway Administration (FHWA) provides high-quality information to serve the Government, industry, and public in a manner that promotes public understanding. Standards 

and policies are used to ensure and maximize the quality, objectivity, utility, and integrity of its information. 

FHWA periodically reviews quality issues and adjusts its programs and processes to ensure continuous quality 

improvement.

October 2009 FHWA-HRT-09-057

HRDS-05/10-09(3M)E

MUT intersections are most readily applicable under the 

following conditions: 

•	 Locations where heavy side street through volumes, relatively low to medium side street left-turn 

volumes, and moderate to heavy left-turn volumes 

from the major road exist.

•	 Locations where median widths are more than 

40 ft, or if median widths are less than 40 ft, locations 

where loons can be installed to accommodate 

large truck movements.

•	 The minor road total volume to the total intersection 

volume ratio is typically less than or equal to 0.25.

Highway agencies may decide that an MUT intersection 

is not applicable if left-turn efficiency is a problem or 

if right-of-way availability is limited.

Summary

A full MUT intersection reroutes both major street 

and minor street left-turning vehicles through one-way 

median openings located several hundred feet from 

the main intersection. This eliminates all left turns from 

the main intersection, reducing conflict points. It also 

allows two-phase signal controls at the intersection and 

the signalized U-turn crossovers. The benefits of the 

MUT intersection include increased capacity and safety. 

More details can be found in the full AIIR report available from the Federal Highway Administration.

References

1. American Association of State Highway and 

Transportation Officials. (2004). A Policy on Geometric 

Design of Highways and Streets, Washington, DC.

2. Jagannathan, R. (2007). Synthesis of the Median 

U-Turn Intersection Treatment, Safety, and Operational Benefits, FHWA-HRT-07-033, Federal Highway 

Administration, Washington, DC. 

3. Maki, R.E. (1992). Directional Crossovers: Michigan’s 

Preferred Left-Turn Strategy, Michigan Department 

of Transportation, Lansing, MI.

4. Scheuer, M. and Kunde, K.L. (1996). Evaluation of 

Grand River Avenue (M-5/M-102) Safety Improvement 

Project Before and After Study, Michigan Department 

of Transportation, Lansing, MI. 

5. Castronovo, S., Dorothy, P.W., Scheuer, M.C., and 

Maleck, T.L. (1995). The Operational and Safety 

Aspects of the Michigan Design for Divided 

Highways, Vol. I, Michigan State University College of 

Engineering, East Lansing, MI.