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Legal Basis for Establishment of Minnesota Trunk Highways

Legislative and Constitutional Routes. Like California and Utah (and probably other states), state highways (officially called "trunk highways") must be specifically authorized by law. The "Babcock Amendment," a constitutional amendment enacted by popular vote in 1920, set the stage for the current system of establishing highways; it listed 70 specific routes that would constitute the trunk highway system, and provided that the Legislature can add additional routes. These 70 routes ("Constitutional Routes") are therefore fixed in law and could only be changed by a constitutional amendment. All other routes ("Legislative Routes") can be added or removed by the Legislature. It should be noted that the Minnesota Constitution was revised in the late 1960s by moving many of its complicated provisions to statute, and among the sections moved was the list of constitutional trunk highways.

All sections of trunk highway are therefore either one of the "Constitutional Routes" or have been authorized by the legislature. All segments of authorized trunk highways, including Constitutional Routes, are described in Minnesota Statutes Chapter 161. These provisions describe individual sections of highway by starting and ending point, as well as any major towns it may pass through, and assign a sequential "Legislative Route" (L.R.) number. Especially with the Constitutional Routes, a change in the alignment of a trunk highway that causes it to miss a locality included in the route description may require establishment of a new Legislative Route. However, as described below, and unlike these other states, there is not necessarily a one-to-one correspondence between a marked trunk highway and an authorized Constitutional or Legislative route. An example of a legislative route description follows (Minn. Stat. 161.115):

Subd. 31. Route No. 100. Beginning at a point on Route No. 22 at or near Gaylord, thence extending in an easterly direction to a point on Route No. 3 westerly of Red Wing; affording Gaylord, Henderson, New Prague, Northfield, Cannon Falls and Red Wing a reasonable means of communication each with the other and other places within the state.

Note that the "Route Numbers" in this provision are not necessarily the marked trunk highway number. MnDOT may number the route as it wishes, and in the example above, Route 100 is marked as MN-19 between Gaylord and Red Wing; Route 22 is MN-22, and Route 3 is U.S. 61. MN-19 extends west from Gaylord as well, authorized as other Legislative Routes.

There are four separate groups of state trunk highways listed in the statutes (note direct links to statutes on the Minnesota North Star server):

  1. Constitutional Routes. (Minn. Stat. 161.114) This section lists the constitutional routes provided by the Babcock Amendment (click here for list). Because they were authorized by a constitutional amendment, routes 1 through 70 are permanently fixed and cannot be removed without another constitutional amendment. Any other routes (71 and higher) established by the legislature can be removed by a subsequent act of the legislature. (When the format of the Minnesota Constitution was modified to reduce verbiage, the routes listed in the Constitution were moved to Minnesota Statutes, even though these routes are not subject to change).
  2. Legislative Routes. (Minn. Stat. 161.115) This includes all routes authorized by the Legislature since 1920, other than those listed below, and currently go up to L.R. 338.
  3. Interstate Routes. (Minn. Stat. 161.12) Even though most interstates were constructed over previously authorized (and usually Constitutional) routes, they have separate Legislative Route numbers not in the sequence of other routes. Certain routes constructed with Federal interstate dollars are not subject to the limits on mileage in the trunk highway system. These separately authorized routes are numbered L.R. 390-396.
  4. Other Authorized Routes. (Minn. Stat. 161.117) There are a few routes that can be established by order of the Commissioner of Transportation. Some of these were the routes involved in the Hennepin County highway swap in 1988. Currently these are numbered L.R. 380-384. Another statute (Minn. Stat. 161.13) allows MnDOT to designate short connecting routes between Interstate highways and the old route bypassed by the freeway in six specified locations (no L.R. numbers were specified for these segments). Only one such route was authorized (MN-324 between I-35 and MN-361 [old U.S. 61] at Pine City), and this was recently turned back.

When MnDOT turns back a section of road, the legislation that authorized that portion may or may not be modified or removed to reflect the change in jurisdiction. There are numerous routes previously authorized and still in the statutes that are no longer state highways (particularly in the Twin Cities Metro area). A few of these routes have been removed from statutes.

Other routes marked as trunk highways. In the past, the state has marked a few short segments of roads under county or city jurisdiction as continuations of trunk highways even though they are not part of the trunk highway system. From 1920 to 1933, the continuation of trunk highways entering Minneapolis and St. Paul were marked through the cities, even though they were not themselves trunk highways. Short sections of other highways were also marked for continuation purposes, though most were later added to the trunk highway system. I'm not aware of any such routes existing today except for a few business routes.


How Minnesota Highways Are Funded

The Minnesota Constitution provides a formula for distributing gasoline tax and auto registration fee revenues and funding of highways. Monies paid into these taxes go into the Highway Users Fund, are distributed as follows: 62 percent goes to the Trunk Highway Fund, 29 percent to the County State-Aid Highway Fund, and 9 percent to the Municipal State-Aid Fund. Counties can designate some of the roads under their jurisdiction as County State-Aid highways (abbreviated CSAH). Not all county routes are CSAH; some are funded strictly from local county funding sources. In addition, cities can designate up to 20 percent of their street mileage as municipal state-aid streets. This qualifies construction and maintenance expenses on these streets to be funded in part from the state gasoline tax. Unlike County State-Aid Highways, municipal state-aid streets are not marked or numbered.

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Originally uploaded December 19, 1997 Last updated December 3, 2006