From the FHWA website:
“The Manual on Uniform Traffic Control Devices for Streets and Highways or MUTCD defines the standards used by road managers nationwide to install and maintain traffic control devices on all public streets, highways, bikeways and private roads open to public travel”. It is “a compilation of national standards for all traffic control devices including road markings, highway signs and traffic signals.“

The MUTCD covers every aspect of street and roadway design. This includes the design of crosswalks and all sorts of pedestrian and bicycle facilities. If bicycle or pedestrian advocates want “Super Sharrows”, “Green Lanes” or other kinds of innovative treatments, they usually have to be part of the MUTCD to be approved for use on city streets.

Though it’s been around since the 1970s, starting in 2009 states were required to adopt the MUTCD as their legal State standard, and some traffic engineers treat the manual the way a religious fundamentalist treats the bible. Part of the reason for this is that following the MUTCD protects engineers, cities, and states from liability. During the last 50 years, Federal and state courts have adopted what’s known as the “Arbitrary and Capricious” standard for most state and federal agencies. As long as an agency isn’t doing something that a court can construe as “arbitrary or capricious” (meaning “random”, “malicious” or “non-standard”) then they are protected against lawsuits. When it comes to street and road design, the MUTCD provides a legal standard of what is considered good, accepted practice. So even if some of its standards are horribly dangerous or exclusionary for pedestrians or bicyclists, as long as an engineer follows it, they can’t be sued if someone gets killed or if cyclists or pedestrians are effectively excluded from using or crossing a public street or highway.

The MUTCD covers things like “Signal warrants”– how much car, pedestrian or bike traffic is needed to qualify for a particular traffic signal type, or 4-way stop, crosswalks or other kinds of street treatments. We frequently hear that “There’s not enough people crossing at this intersection to warrant a traffic signal”, even when multiple people have been injured or killed and there is a popular destination on the other side of the street (such as a school, bus station or retail shop). This is partly the reason why we often have half-mile or mile distances between traffic signals on major 4-lane roads like Snelling Avenue, Rice Street, Shepard Road or parts of West 7th Street. Signal warrants can present a “chicken and egg” problem: you can’t get a traffic signal installed unless more pedestrians cross, but more pedestrians aren’t going to cross without a signal or other measures to make that crossing safer. Engineers can get “Variances” from warrants, but they are required to do a lot of extra work to demonstrate why a variance is necessary and they potentially expose themselves and their cities to legal liability.

The MUTCD requires municipalities and states to project future motor vehicle traffic growth and account for this in street and road designs, but it doesn’t require the same protections for pedestrians or cyclists. A new housing development, like what’s going in at the old Ford Site in Saint Paul, may generate more motor vehicle traffic, but it’s also going to generate lots more pedestrians and cyclists who’ll want to use Mississippi River Road, Ford Parkway and other neighborhood streets and sidewalks for biking, walking dogs, jogging, or other forms of recreation. But the city isn’t required by the MUTCD to forecast this growth in pedestrian and bikeway demand or account for it in street designs.

If a community group or city mayor wants to lower posted speed limits on a major arterial city street, they can’t just unilaterally do it. The MUTCD requires that they do an “85th percentile study”. The local agency has to go out and study the speed that most folks actually drive on the roadway and then set the speed limit at 85% of this.

Another way I’ve encountered the MUTCD is when it comes to physically protecting cyclists and pedestrians. If pushed, DOT’s will sometimes put in pedestrian refuge islands or sidewalk bump-outs. They will either do it permanently, just making a raised area with curbs, or they’ll do it temporarily, using plastic poles. But these refuge islands don’t physically or psychologically protect a pedestrian. An errant vehicle could still easily kill a pedestrian standing in the refuge island, and many of the temporary bump-outs or protected bike lanes regularly get their poles or signage mowed down by cars. What’s needed is concrete bunkers, concrete or steel bollards, or temporary concrete jersey barriers which will actually stop a car that’s about to hit the pedestrian or cyclist. A few cities use these and state highway departments will allow their use to protect their own workers from cars near road work and construction sites, but they won’t allow their use them on city streets. I am sometimes told that the “Highway manual doesn’t allow us to use them” or, if they’re used, they require protective devices at the ends or in front of them to cushion their impact on errant cars. Similarly, some DOTs regard sidewalks as an “Auto Recovery Zone” or “Clear Zone” and prohibit trees, planters, or large stationary objects near the street or roadway so errant motor vehicles have room to “recover” when they run off the road. This design mentality is understandable on freeways, but on city streets it’s part of the reason that so many people get hit by cars at bus stops, on sidewalks, in bike lanes, or even inside buildings.

In these and many other ways, the MUTCD is overwhelmingly oriented towards motor vehicles with the goal of moving as many motor vehicles as possible as quickly as possible. Yet 25% of the public has no driver’s license and this percentage is probably even higher in cities. And while overall severe injuries and deaths of the nation’s drivers have gone down, pedestrian and cyclist deaths have remained stubbornly high. 2020 may set a new record for pedestrian injuries and deaths.

The MUTCD is supposed to be updated periodically to accommodate the nation’s changing transportation needs and to address new safety technologies, traffic control tools, and traffic management techniques. But these updates are few and far between. The latest version of the manual came out in 2012, so it hasn’t been updated for nearly 10 years. The good news is that it’s getting updated now. The FHWA is accepting comments on the manual up until May 12. America Walks, The League of American Cyclists and other groups are pushing for progressive changes in the document and have created write-in campaigns for comments. The America Walks campaign is at–
https://americawalks.org/urgent-action-alert-demand-a-better-recipe-book-for-safer-streets/

So, if you have pet peeves about the MUTCD and state highway manual design guidelines, this is the time to say something and write in.