Highway

Below is MaineDOT's methodology to provide a fair, structured framework to prioritize programs and projects. There are two parts - the Highway Corridor Priority (HCP), and the Customer Service Level (CSL).

See the glossary for the descriptions of each level in the priorities.

This data is available for viewing in the MaineDOT Map Viewer.

Highway Corridor Priority (HCP)

The first part of the method, the Highway Corridor Priority (HCP), categorizes our highway assets into six levels of priorities.

Highway Corridor Priority	Miles	% Miles	% Traffic	Example (click on thumbnail to view image)/th>
Priority 1	1881	8%	43%	The Interstate and all other National Hwy System corridors, such as Brewer-Calais Rte 9, Newport-Gilead Rte 2, Houlton-Madawaska Rte 1
Priority 2	1246	5%	18%	High-priority, non-NHS such as Caribou-Ft. Kent Rte 161, Bangor-Greenville Rte 15, Ellsworth-Eastport Rte 1, Farmington to Rangeley Rte 4
Priority 3	1306	6%	11%	China-Hampden Rte 202, Cornish-Fryeburg Rte 5, Lincoln-Topsfield Rte 6, Baileyville to Houlton Rte 1
Priority 4	4598	20%	16%	Major/Minor Collectors not included above (including 3 miles of marine highway)
Priority 5	14489	62%	13%	Local Roads & Streets

 * Data based on 2025 asset inventory.

Customer Service Level (CSL)

The second part of the method is determining the Customer Service Level (CSL) that measures MaineDOT managed highway assets (Priority 1-5) in three areas. The CSL uses customer-focused engineering measures to track highway (1) Safety, (2) Condition and (3) Serviceability, and grades them similar to a report card (A – F). The information below lists the individual measures that make up the overall service level grade. To view this data in our map viewer, click on a header below.

CSL Mileage Summary Charts

Highway Corridor Priority and Customer Service levels are overlaid to show an aggregated state-wide view of the different priority roads with their corresponding service levels. Percentages do not reflect highway assets not managed by MaineDOT.

Current Highway CSL Miles by Priority

Updated for projects with Construction Complete Dates on or before Monday, June 01, 2026.

Condition

HCP	A	B	C	D	F	Total
1	433	447	450	92	71	1,493
2	467	417	203	94	39	1,220
3	635	377	170	85	25	1,291
4	2,821	1,040	502	184	32	4,580
Total	4,356	2,280	1,325	456	166	8,584

Safety

HCP	A	B	C	D	F	Total
1	304	610	375	157	70	1,516
2	264	484	296	150	47	1,240
3	388	475	262	144	35	1,304
4	998	1,798	863	577	360	4,596
Total	1,954	3,367	1,796	1,027	512	8,657

Service

HCP	A	B	C	D	F	Total
1	1,012	373	111	14	7	1,516
2	871	256	86	17	10	1,240
3	1,031	181	45	44	3	1,304
4	2,112	105	2,373	4	2	4,596
Total	5,026	915	2,615	78	22	8,657