Michigan Highways: Since 1997.

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M-22 & M-109 junction route signage in Glen Arbor, Michigan

Controlled-Access Highways

Freeway vs. Expressway

This page helps define the terms Controlled-Access, Limited-Access, Freeway, and Expressway as they are used both on the Michigan Highways website and in the "official" world of transportation planning and highway engineering. One of the attributes of each state trunkline highway route as detailed in the Route Listings portion of the site is its "Controlled-Access status." (Other attributes include length of the route, termini, historical notes, etc.) Since the meaning of the terms "freeway" and "expressway" have changed over the decades and can be different in different parts of North America, this site uses the technical definition as employed by transportation planners, engineers and agencies for consistency. But first, we need to define these terms.


Controlled-Access Highway – Designed exclusively for high-speed, unhindered vehicular traffic, with no traffic signals, intersections, or property access. These highways are free of any at-grade crossings with other roads or railroads, which instead use overpasses and underpasses to cross the highway. Entrance and exit to the highway is provided by ramps at interchanges. Opposing directions of travel are usually (but not always) separated by a median or some sort of traffic barrier. Generally, pedestrians, non-motorized vehicles and farm machinery are not allowed on these types of highways, although some exceptions do exist in certain areas.

Limited-Access Highway – A highway or arterial road for high-speed traffic which has many characteristics of a Controlled-Access highway (see above), including limited or no access to adjacent property, some degree of separation of opposing traffic flow, the use of grade-separated interchanges to some extent, and few or no intersecting roadways. Unlike Controlled-Access highways, pedestrians, non-motorized vehicles (e.g. bicycles), and farm machinery are not explicitly prohibited (although exceptions may exist). However, with the variation across the spectrum of Limited-Access Highways—some are essentially freeways with 70 mph speed limits, save for one or two remaining crossroads yet to be grade-separated, while others are simply 55 mph two-lane rural highways which happened to be constructed on a Limited-Access right-of-way and feature copious intersecting crossroads—it would be generally advisable for non-motorized vehicles and pedestrains to avoid using many of the state's Limited-Access Highways, for safety's sake if no other reason.

Freeway – In official use, a Freeway is the same as a Controlled-Access Highway. During the 1950s and 60s, freeways were often referred to as "expressways" in many parts of North America and still are in certain areas. Even today in some areas, freeways bear the name "Such-and-Such Expressway" even though the actual highway itself is constructed to freeway standards. In Chicago, for instance, all but one of the freeways are called "Expressway" (e.g. Dan Ryan Expwy, Eisenhower Expwy, Kennedy Expwy—the exception being the Bishop Ford Frwy) while the public almost universally refers to the freeway system as "expressways." On the other hand, in Detroit all of the former "Expressways" have slowly become known as "Freeways" (e.g. John C. Lodge Expwy and the Davison Expwy are now named the John C. Lodge Frwy and Davison Frwy). While the names of the freeways in Greater Detroit are now all officially "Freeway," you may still hear the "Freeways" referred to as "expressways" by certain segments of the population.

Expressway – In official use, an Expressway is the same as a Limited-Access Highway. Some states, like neighboring Wisconsin, make heavy use of Expressways, while they are rather rare in Michigan. This is because in the 1950s, State Highway Commission John C. Mackie saw the benefit in upgrading corridors directly to freeway standards regardless of whether it bore an Interstate route designation or not. Other states concentrated their freeways in the Interstate corridors, leaving other primary routes as expressways (limited-access highways).

Some highway departments have used expressways as a stepping-stone to eventually constructing a route to full freeway standards. In Michigan, the US-31 St Joseph Valley Pkwy between Niles and Berrien Springs was originally opened to traffic as an expressway—with limited access only at certain cross roads. Over the following several years, each intersecting roadway was either closed or a grade separation (overpass or underpass) was constructed. Once the final intersecting road was grade-separated, that portion of US-31 officially became a freeway and, accordingly, the speed limits were raised from 55 to 70.

Site Usage

In the Route Listings on the Michigan Highways website, the values given for the lengths of any Freeway or Expressway mileage along any route is based primarily on two things: MDOT Right-of-Way Maps and common sense. The Right-of-Way Maps indicate the limits of the public right-of-way along a state trunkline highway as well as if there is any control of access present. (In Michigan, a motorist can often spot a Controlled- or Limited-Access highway by the existence of a "right-of-way fence" along the edge of the highway's right-of-way.) Areas where access to the highway right-of-way from adjacent properties has been disallowed (or "controlled") are shown with a distinctive symbol on the maps.

While Access Control is rather well-defined, making a determination of which portions of a route are specifically controlled as Freeways (Controlled-Access) or Expressways (Limited-Access) is not as precise. The principle of common sense, therefore, has been used to delimit where a freeway segment, for example, transitions to an expressway segment.

For example, as US-31/BL I-196 enters the City of Holland from the south, it does so as a fully Controlled-Access Freeway. After passing through the Washington Ave/Blue Star Hwy interchange (Exit 47), the highway transitions to a Limited-Access Expressway. The transition point, as noted on this website, has been placed just south of the Central Ave intersection where the southbound US-31 Michigan Left turnaround to northbound US-31 (and Central Ave) occurs. South of this point, the route is considered a Freeway, while north of that location, it is an Expressway.

Even in situations where short "quasi-freeway" segments occur, such as along further to the north along US-31 in the Holland area between 8th Ave and James St (complete with two full freeway-style interchanges at BL I-196/Chicago Dr and Lakewood Blvd), those segments are simply considered to be part of the overall Expressway portion of the route. While one could theoretically classify segments like these as short freeways, unless there seems to be a specific intent to convert that segment into a longer freeway in the future, this site will continue to classify those as being part of the Expressway portion of the route.

Additional Information