Current through 2022-14, April 6, 2022

A. General

The original criteria used in 1975 serve well to distinguish arterial from collector highways. In order to make a distinction between collector and local highways, the following five criteria will be used in conjunction with the 1975 criteria:

1. Land Use
2. Relative Annual Average Daily Traffic (AADT)
3. Trip Length
4. Network Configuration and Continuity
5. Route Spacing

In all cases, if a route generally meets three out of the five criteria, with Land Use, Relative AADT, and Trip Length having a heavier weight in the criteria, then the route will be considered a collector.

If the above criteria are not applicable, then three additional criteria will be used to make a distinction between collector and local highways. In all cases, if a road meets all of the following three criteria, it will be designated a collector:

1. The road has a State Route Number assigned to it,
2. The road is within a city, town or plantation, and
3. The road provides direct access to a significant acreage of Maine Public Reserve Land.

If the above criteria are not applicable, then the following additional criteria will be used to make a distinction between minor collector and local highways. In all cases, if a road meets all of the following criteria, it may be designated a minor collector/State Aid:

In order to promote continuity in the state-aid highway system, and

1. Not withstanding any existing laws, rules and regulations, and
2. Subject to a signed petition representing the majority of municipal officers of the requesting municipality(ies), and
3. IF it enables the connection of a State Aid road presently NOT connected on one end to a State Highway or State Aid, and
4. IF the present TOWNWAY/LOCAL section is SHORTER than the connecting STATE AID in question,

Then, based on meeting ALL of the above criteria:

MDOT may, upon review, accept a road that is classified LOCAL / designated TOWNWAY to be a Minor Collector State Aid Highway.

In addition, overall Federal Highway Administration percentage guidelines for federal functional classes of Maine roads must be satisfied and this could affect any future reclassification efforts.

Current main office staff knowledge, Maintenance Division Engineers, and file information, supplemented by local input, will be used in the application of this and the following criteria.

B. LAND USE (Density of Development - Presence of Traffic Generators)

Land use criteria will be considered for those roadways and city streets which have previously been or would tend to be classified in the minor collector or local category.

1. Collectors or Arterials Generally Serve:
a. Regional shopping
b. Industrial parks and free standing manufacturing or processing plants employing a substantial number of persons.
c. Recreational uses such as golf courses, marinas, horse racing tracks, and major boat landings.
d. Institutional uses such as regional schools, colleges, and hospitals.
e. Military bases or regional airports.
2. Roadways and streets classified as "Local" are expected to service the following land uses and minor traffic generators:
a. Residential neighborhoods and strip residential development.
b. Local businesses.
c. Farms.
d. Agricultural or timber lands.

The Annual Average Daily Traffic (A.A.D.T.) varies widely throughout the State due to heavily and sparsely populated areas. Therefore, Annual Average Daily Traffic per se is not a direct input for criteria in determining functional highway classifications, but will be used on a percentage basis relating the individual communities' urban areas (inside the Maine Department of Transportation compact area) and the rural areas separately.

The highway functional classification indicated by this criteria will be determined by multiplying the average of the area's three (3) highest traffic volumes (latest existing area wide traffic volumes) by the following percentages:

Highway Classification Percent of Average Volume
Collector 16-39
Local 0-15

In determining the average of the three (3) highest volumes in urban areas, only one (1) of the three volumes will be taken from the Central Business District (CBD).

The resulting volume will be compared to available traffic information on specific facilities to categorize roadways into the above groups, under this criterion.

Additionally, the presence of heavy trucking will tend to associate with collector facilities. This will be considered to the extent information is available.


Trip Length will be incorporated into the study by considering the following:

Functional classification defines the role that any particular road or street serves in accommodating the flow of travel through a highway network. The following guidelines describe the type of travel generally associated with the various functional classes:

Collector Travel distances are shorter than those on the Arterial system. Primarily serves trips from local residential areas, commercial/industrial area, and locally important traffic generators such as, consolidated schools, hospitals, etc., to the arterial system.

Local Predominant travel distances are short. Predominantly serves travel from adjacent land areas to the arterial and collector systems.

Data to be used include ADT, available mapping, field reviews and local input.


Continuity and configuration of the functional systems will vary with population density. The following guidelines are general and may vary depending upon the type of area served by the roadway under consideration.

1. Collector System. Serves as local feeder routes connecting local service roads to the arterial systems. In urban areas routes on this system should be configured such that they serve the function of linking residential neighborhoods, commercial/industrial areas and locally important traffic generators with the arterial systems. Generally collectors have no stub ends or do not include dead end roads. A traffic route number would generally associate with a collector.
2. Local Service System Consists of all roads not classified as Arterials or Collectors. These roads which can connect with any of the functional classes of roadway serve the function of carrying travel from adjacent land areas to the arterial and collector systems. No traffic route numbers are usually formed on local service-facilities.

Special care will be used in assuring continuity between rural and urban designations in the vicinity of compact lines and designation changes will be made at logical breaks in facility service. Generally, urban designations will be at least equivalent to rural designations at those transition points.

A review of area mapping and available aerial photography will generally establish the distinction between locals and collectors from a network configuration and continuity standpoint.


Routes on the Arterial System shall be spaced so that all developed areas of the State are within reasonable distance of an arterial highway.

Routes on the Collector System shall be spaced at intervals, consistent with population density to provide service to locally important traffic generators such as, consolidated schools, hospitals, etc.

Spacing of highways with like functional classification shall be evaluated to assure that their geographical distribution provides the desirable levels of service.

In the event parallel routes are determined to provide identical function, a determination will be made as to which of the routes predominate and other parallel route(s) will revert to the next lower functional classification.

Available mapping and aerial photography will provide the basis for use of this criterion.


The following guidelines will determine the extent of functional systems and will be applied on a Statewide and on an individual urban area basis. The rural guidelines will also be applied on a county basis but a reasonable variation will be allowed, if offset by other counties so that the Statewide percentages are met. If the percentage guidelines indicate adjustments are desirable, a reevaluation of marginal roads in communities least affected by the reevaluation will be made in order to comply with the percentage guidelines on a statewide basis.


Percentage of Total
Rural Miles
Arterial System 6 - 12
Collector System 15 - 30
Local Road System 60 - 75


Percentage of Total
Rural miles
Arterial System 15 - 25
Collector System 5 - 10
Local Road System 65 - 80


17-229 C.M.R. ch. 304, § 02

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