Section 229-299-A-2 - TECHNICAL STANDARDSDriveways onto any state and state aid highway located outside urban compact areas must comply with the basic safety standards in Section 2.1. If the driveway is onto a Mobility Arterial, it must also comply with the additional or increased standards set forth in Section 2.2. If the driveway is onto a Retrograde Arterial, it must also comply with the additional or increased standards set forth in Sections 2.2 and 2.3.
2.1. Basic Safety Standards A. Sight Distance. The minimum allowable sight distances for all accesses onto all state and state aid highways located outside urban compact areas are set forth in Table 1. MaineDOT may require up to 50% greater sight distances when at least 30% of the traffic using the driveway will be by larger vehicles. Table 1 - Sight Distance
| Posted Speed (MPH) | Sight Distance (Feet) |
| 20 | 155 |
| 25 | 200 |
| 30 | 250 |
| 35 | 305 |
| 40 | 360 |
| 45 | 425 |
| 50 | 495 |
| 55 | 570 |
| 60 | 645 |
B. Driveway Width. Unless a waiver is granted pursuant to Section 3.3(C), driveway width within the highway right of way must be between 12 and 22 feet inclusive. The width of a driveway is the distance across the driveway, excluding radii, measured parallel to the highway.C. Corner Clearance. Unless a waiver is granted pursuant to Section 3.3(C), the minimum corner clearance for driveways is 75 feet for un-signalized intersections and 125 feet for signalized intersections except that at no time will a driveway be located on the radius of the two intersecting roadways.D. Turnaround Area / Parking. Driveways will be designed such that all maneuvering and parking of any vehicles will take place outside of the highway right of way and such that vehicles may exit the premises without backing onto the highway traveled way or shoulder. All driveways will have a turnaround area at least 8 feet wide by 15 feet long. MaineDOT may require a larger turnaround area to accommodate larger vehicles that are expected to use the driveway on a regular basis. Where the state or state aid roadway speed limit is posted at or below 35 mph, a waiver may be granted, in accordance with Section 3.3(C) for a use in existence as of May 25, 2002 that proposes a driveway alteration or change of use so long as the change of use generates no more than 50 trips per day.E. Drainage Standards. (1) Culvert Size. Pursuant to 23 M.R.S.A. §705, MaineDOT will determine the diameter of culverts within the highway right of way depending upon local conditions.(2) Construction and Maintenance Standards. Driveways, on-site ditches, swales, pipes and other structures that direct runoff toward MaineDOT ditches or drainage systems must be constructed, crowned, stabilized and maintained with stable materials and appropriate erosion control measures such as permanent vegetation or stone.(3) Mitigation. If the proposed development poses a significant drainage risk, then the applicant must mitigate the impacts of increases in peak flow from storms into MaineDOT drainage systems through measures specified by MaineDOT, unless a waiver is granted pursuant to section 3.3(C). Mitigation measures may include on-site controls, off-site improvements, or payment of a fee pursuant to 23 M.R.S.A. §57-A. A "significant drainage risk" exists (a) when the applicant proposes a fixed connection to a closed system drainage structure owned by MaineDOT or (b) when MaineDOT determines, using accepted engineering and hydrologic principles, that: (i) the proposed driveway has a grade of 10% or greater for a length of 150 feet or more draining toward the highway; (ii) the proposed development has more than 10,000 square feet of impervious surface draining toward the highway, or (iii) the proposed development will substantially contribute to the failure of a downstream MaineDOT facility. "Impervious surfaces" are the footprint of buildings, pavement, gravel, or other low-permeability or compacted surfaces, not including natural or man-made water bodies. "Peak flow" is the greatest rate of flow in a drainage way, measured as volume per unit of time, resulting from storms up to a 50-year event.F. Intersection Angle / Radius of Edges. To the maximum extent practical, the driveway will be constructed perpendicular to the highway at the access point. The minimum radius on the edge of a driveway, if any, must be 10 feet. MaineDOT may require that the edges of the driveway have a radius if larger vehicles are expected to use the driveway on a regular basis.G. Double Frontage Lots. Unless a waiver is granted pursuant to Section 3.3(C), driveways for lots with frontage on a Non-compact Arterial and another public way, will be restricted to the other public way, unless MaineDOT determines that queuing of traffic entering a driveway off the other public way would interfere with traffic on the Non-compact Arterial due to insufficient lot frontage along the other public way. If the other public way is a mobility or retrograde arterial, the driveway must be located on the highway frontage that allows the intent of this rule to be most effectively and efficiently met.2.2. Mobility Arterial Standards In addition to the standards in Section 2.1, driveways onto Mobility Arterials must also comply with the increased or additional standards in this Section 2.2.
A. Mobility Sight Distance. Unless a waiver is granted pursuant to Section 3.3(C), the sight distance for driveways onto Mobility Arterials must meet or exceed the distance listed in Table 2. Sight distance is measured in accordance with its definition. Table 2 - Mobility Sight Distance
| Posted Speed (MPH) | Sight Distance (Feet) |
| 20 | Not applicable |
| 25 | Not applicable |
| 30 | Not applicable |
| 35 | Not applicable |
| 40 | 580 |
| 45 | 710 |
| 50 | 840 |
| 55 | 990 |
| 60 | 1,150 |
B. Spacing Between Driveways. Unless a waiver is granted pursuant to Section 3.3(C), new driveways onto Mobility Arterials must be separated from other existing or proposed driveways or entrances including those located across the highway and those serving the same lot, in accordance with the minimum spacing standards set forth in Table 3. Driveway spacing is measured from edge of proposed driveway/entrance to edge of driveway/entrance, excluding radii. Driveways or entrances located directly across the highway from the proposed driveway are not counted in applying the spacing standard.Table 3 - Minimum Driveway Spacing Standards
| Posted Speed (MPH) | Driveway Separation (Feet) |
| 25 or less | Not applicable |
| 30 | Not applicable |
| 35 | Not applicable |
| 40 | 175 |
| 45 | 265 |
| 50 | 350 |
| 55 or more | 525 |
C. Mobility Arterial Corner Clearance. The minimum corner clearance for driveways onto Mobility Arterials must be 125 feet, except as provided in Section 2.2(D) and unless a waiver is granted pursuant to Section 3.3(C). The Department of Transportation may require greater corner clearance if the department determines it is necessary to prevent a significant impact on public safety or a reduction in the posted speed limit.D. Controlled Access Off-Ramp Setback. The minimum corner clearance for driveways onto Mobility Arterials from a controlled access off-ramp must be 500 feet, unless a waiver is granted pursuant to Section 3.3(C). Minimum corner clearance for driveways onto Mobility Arterials from controlled access on-ramps must meet the requirements of section 2.2(C).E. Shared Driveways. Whenever possible, property owners will seek opportunities for shared driveways onto Mobility Arterials. 2.3. Retrograde Arterial Standards In addition to the applicable standards in Sections 2.1 and 2.2, applicants for driveways onto Retrograde Arterials may be required to create or expand paved shoulders for a length not to exceed 75' on either side of the proposed driveway and pave the apron of the proposed driveway if MDOT reasonably determines that, when built, the driveway will significantly impact public safety or will necessitate a reduction in posted speed.
17-229 C.M.R. ch. 299, § A-2