Current through 2022-14, April 6, 2022

A. Rural

Rural principal arterial system

The rural principal arterial system consists of a connected rural network of continuous routes having the following characteristics:

1. Serve corridor movements having trip length and travel density characteristics indicative of substantial statewide or interstate travel.
2. Serve all, or virtually all, urban areas in Maine.
3. Provide an integrated network without stub connections except where unusual geographic or traffic flow conditions dictate otherwise (e.g., international boundary connections and connections to coastal cities).

The principal arterial system is divided into the following two categories:

Interstate System. The Interstate subclassification consists of all presently designated routes of the interstate System.

Other principal arterials. This subclassification consists of all non-Interstate principal arterials.

Rural minor arterial road system

The rural minor arterial road system should, in conjunction with the principal arterial system, for a rural network having the following characteristics:

1. Link cities and larger towns (and other traffic generators, such as major resort areas, that are capable of attracting travel over similarly long distances) and form an integrated network providing interstate and intercounty service.
2. Be spaced at such intervals, consistent with population density so that all developed areas of the State are within a reasonable distance of an arterial highway.
3. Provide (because of the two characteristics defined immediately above) service to corridors with trip lengths and travel density greater than those predominately served by rural collector or local systems.

Minor arterials therefore constitute routes whose design should be expected to provide for relatively high overall travel speeds, with minimum interference to through movement.

Rural collector road system

The rural collector routes generally serve travel of primarily intracounty rather than statewide importance and constitute those routes on which (regardless of traffic volume) predominant travel distances are shorter than on arterial routes. Consequently, more moderate speeds may be typical, on the average.

In order to define more clearly the characteristics of rural collectors, this system is subclassified according to the following criteria:

Major collector roads. These routes generally:

1. Provide service to any county seat not on an arterial route, to the large towns not directly served by the higher systems, and to other traffic generators of equivalent intracounty importance, such as consolidated schools, shipping points, county parks, important mining and agricultural areas, etc.;
2. Link these places with nearby larger towns or cities, or with routes of higher classification; and
3. Serve the more important intracounty travel corridors.

Minor collector roads. These routes are generally:

1. spaced at intervals, consistent with population density, to collect traffic from local roads and bring all developed areas within a reasonable distance of a collector road;
2. provide service to the remaining smaller communities; and
3. link the locally important traffic generators with their rural hinterland.

Rural local road system

The rural local road system should have the following characteristics:

1. Serve primarily to provide access to adjacent land; and
2. provide service to travel over relatively short distances as compared to collectors or other systems.
B. Urban

Urban principal arterial system

In every urban environment there exists a system of streets and highways which can be identified as unusually significant to the area in which it lies in terms of the nature and composition of travel it serves. In smaller urban areas these facilities may be very limited in number and extent, and their importance may be primarily derived from the service provided to travel passing through the area. In larger urban areas, their importance also derives from service to rural oriented traffic, but equally or even more important, from service for major movements within these urbanized areas.

This system of streets and highways, called here the urban principal arterial system, serves the major centers of activity of a metropolitan area, the highest traffic volume corridors, and the longest trip desires; and carries a high proportion of the total urban area travel on a minimum of mileage. The system is usually integrated, both internally and between major rural connections.

The principal arterial system carries the major portion of trips entering and leaving the urban area, as well as the majority of through movements desiring to bypass the central city. In addition, significant intra-area travel, such as between central business districts and outlying residential areas, between major inner city communities, or between major suburban centers is served by this class of facilities. Frequently, the principal arterial system will carry important intraurban as well as intercity bus routes. Finally, this system in urbanized areas provides continuity for all rural arterials which intercept the urban boundary.

Because of the nature of the travel served by the principal arterial system, almost all fully and partially controlled access facilities is a part of this functional class. However, this system is not restricted to controlled access routes. In order to preserve the identification of controlled access facilities, the principal arterial system is stratified as follows: (1) Interstate, (2) other freeways and expressways, and (3) other principal arterials (with no control of access).

For principal arterials, the concept of service to abutting land is subordinated to the provision of travel service to major traffic movements. It should be noted that only facilities with the "other principal arterial" subclass are capable of providing any direct access to land, and such service should be purely incidental to the primary functional responsibility of this class of roads.

Urban minor arterial street system

The minor arterial street system interconnects with and augments 'the urban principal arterial system and provides service to trips of moderate length at a somewhat lower level of travel mobility than major arterials. This system also distributes travel to geographic areas smaller than those identified with the higher system.

The minor arterial street system includes all arterials not classified as principal and contains facilities that place more emphasis on land access than the higher system, and offers a lower level of traffic mobility. Such facilities may carry local bus routes and provide intracommunity continuity, but ideally should not penetrate identifiable neighborhoods. This system should include urban connections to rural collector roads where such connections have not been classified for internal reasons as urban principal arterials.

Urban collector street system

The collector street system provides both land access service and traffic circulation within residential neighborhoods, commercial and industrial areas. It differs from the arterial system in that facilities on the collector system may penetrate residential neighborhoods, distributing trips from the arterials through the area to the ultimate destination. Conversely, the collector street also collects traffic from local streets in residential neighborhoods and channels it into the arterial system. In the central business district, and other areas of like development and traffic density, the collector system may include the street grid which forms a logical entity for traffic circulation.

Urban local street system

The local street system serves primarily to provide direct access to abutting land and access to the other systems. It offers the lowest level of mobility and usually contains no bus routes. Service to through traffic movement usually is deliberately discouraged.


17-229 C.M.R. ch. 304, § 01

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