Current through 2022-14, April 6, 2022

1. General

Where other arrangements are not feasible, MaineDOT will consider permitting attachment of Facilities on Highway Structures. Each such attachment will be considered on an individual basis, and permission to attach will not be considered as establishing a precedent for granting subsequent requests for attachment. The following requirements are established for attachment to any Highway Structure:

A. P.E. License & Certification

A Maine Licensed Professional Engineer shall design all proposals for attachments to Highway Structures in accordance with the latest AASHTO standards. In the case of Bridges, each design proposal shall be fully evaluated in accordance with the latest edition of AASHTO LRFD Bridge Design Specifications and the Maine Department of Transportation Bridge Design Guide (as applicable) to assess the effect of the attachment(s). A statement certifying that the additional loading will not exceed allowable limits is required as part of the design submittal.

B. Out-of-Service Facilities

All Facilities that are taken out-of-service shall be removed in accordance with Section 7(4), Out-of-Service Facilities.If any such Facilities are not removed, MaineDOT may elect to remove such Facilities at the Authorized Entity's expense.

C. Other Applicable Permits

Authorized Entities are responsible for acquiring any and all permits that may be applicable to their proposed work. Some of the applicable permits may include:

(1) Coast Guard Permits

A Coast Guard permit or notification may be required whenever the proposed work will occur over a navigable waterway.

(2) Railroad Permits

Work permits may be required for any work done over, under or near a Railroad and are obtained directly from the Railroad Company.

(3) Environmental Permits

Permits may be required by the Natural Resources Protection Act (NRPA) administered through the Department of Environmental Protection (DEP), Shoreland Zoning, Army Corps and others.

D. Identification Tag

A permanent tag shall be affixed to each end of the attached Facility identifying the Authorized Entity, the type of attachment, and a contact telephone number. All tags shall be maintained in a legible condition with current information.

E. Communication and Electric Supply Lines

Communication and Electric Supply Lines shall be suitably insulated, grounded, and carried in protective Conduit or pipe from the point of attachment to the point of exit per applicable National Standards.

F. Hazardous Transmittants

Mutually Hazardous Transmittants shall be isolated by compartmentalizing or by auxiliary Encasement of incompatible carriers. This shall include Electric Supply Lines, gas lines, effluent lines and sanitary sewer lines.

G. Casing Vents

Where a pipeline on or in a structure is encased, the Casing shall be effectively opened or Vented at each end to prevent possible buildup of pressure and to detect leakage of gases or fluids.

H. Uncased Attachments

Where a Casing is not provided for a pipeline on or in a structure, additional protective measures shall be taken, such as employing a higher factor of safety in the design, construction and testing of the pipeline than would normally be required for encased construction.

I. Pipeline Shutoffs

Pipeline shutoffs, preferably automatic, shall be required within close proximity of attachments unless other sectionalizing devices can isolate segments of the lines. Shutoff valves shall be located on both sides of a Highway Structure footing.

J. Brackets/Bolt Material

For painted steel structures, all brackets and bolt material in contact with the structure shall be hot-dipped galvanized. For weathering steel (ASTM A588, A709, etc.), all brackets and bolt material shall also meet an applicable ASTM weathering steel designation.

K. Connection Type

All attachments shall be bolted. Bolt holes are normally drilled 1/16inch larger than the bolt diameter. No stainless steel bolts shall be used except on concrete or timber structures.

L. Welding

Welding to steel components is not permitted.

2. Bridges

The following standards are specific to Bridges and in addition to the General Standards listed above.

A. General
(1) First Girder/Beam

All Facilities attached to a Bridge shall not be located outside the first girder or beam, except for precast box beam and voided slab as long as they were originally designed for Facility installation.

(2) Precast & Truss Bridges

Attachments that are not incorporated in the original Bridge design will not be permitted on either precast concrete Bridges or on the main truss members of a truss Bridge.

(3) Vertical Clearances

Vertical clearances for any Highway or Railroad overpasses or for Bridges over navigable waters shall not be reduced from existing conditions.

(4) Conduits in New Bridges

When a request is made during the design phase of a proposed Bridge, MaineDOT may allow Conduits to be incorporated into the construction of the Bridge. The Authorized Entity will be responsible for the additional costs relating to such accommodation. Facilities shall not be allowed in the bridge sidewalk, bridge rail or hollow bridge members that are not of sufficient size to allow maintenance personnel to maintain the structure while protecting the Facility.

(5) Connections to the Bottom of Bridge Decks

No Facility connections shall be allowed to the bottom of the bridge deck.

(6) Load And Resistance Factor Rating (LRFR)

A Utility must perform a LRFR load rating in accordance with the AASHTO Manual for Bridge Evaluation, current edition, and the MaineDOT Load Rating Guide when considering attachment to an existing bridge structure. The Utility shall not be allowed on structures whose legal load ratings are less than 1.0.

(7) Hazardous Transmittant Pipelines

Hazardous Transmittant pipelines shall not be allowed to attach to bridges over traffic. Hazardous Transmittant Pipelines attached to bridges over waterways shall have shutoff valves placed at each end of the bridge. In the event of high water and/or debris threatening or reaching the bottom chord of the bridge, the pipeline shall be shut off on both ends of the bridge until the threatening conditions have subsided.

B. Connection Requirements

Drilled holes in the web area, which are located at least 6 inches from the flanges, are permitted. Attachments to the flanges are not permitted.

(2) Diaphragms

For any attachments located between two steel beams, replacement of the diaphragms with Facility support brackets may be permitted, provided the replacement is equal in strength to the original and of compatible materials.

(3) Holes through Abutments

Any holes through concrete abutments shall be core drilled and sealed with a waterproof seal, such as a link seal, to prevent water leakage and migration of fines.

(4) Approach Slabs

Cutting through concrete approach slabs may be permitted providing the slab is repaired to achieve the same strength as the original design. The method of these proposed repairs are to be reviewed and accepted by MaineDOT.

(5) Electric Supply Lines /Communication Lines

Buried cable shall be carried to a manhole located beyond the back wall and/or approach slabs of the Bridge. Carrier and Casing pipe should be suitably insulated from Electric Supply Line attachments.

(6) Clearances
(a) A minimum offset of 12 inches from any point on the main carrying members (flanges & webs) and substructure units (foundations) to the edge of the outer face of the pipe or insulation is required. Additional clearance may be required for smaller beams or Facilities over 12 inches to ensure adequate access for future maintenance.
(b) Brackets shall be located a minimum of 6 inches above the bottom flange of the steel beams to allow sufficient clearance for rolled staging.
(c) A minimum 2-foot clearance is required on at least one side of any Facility attachment located between beams to allow access for maintenance.
(d) Any attachments to concrete members (such as abutments, piers, and concrete slab superstructures) require a minimum 12-inch clearance.
3. Buried Highway Structures

For buried Highway Structures, the preferred location for any Facilities is at the edge of the right of way or at least 15 feet upstream or downstream from the end of the structure. If it is not possible to be located in this manner and the Facility must be buried in the roadway, a 12-inch vertical clearance from the structure to the Facility is required.

B. Additional Design Requirements

All Facilities and Appurtenances must be located and designed to allow reasonable replacement of Highway Structures. In most cases, excavation slopes will be at least 1.5:1. For example: a 10-foot pipe with 3 feet of fill will necessitate an excavation width at the roadway surface of at least 50 feet in length. Facilities installed within such areas shall be designed and constructed with due consideration given toward providing temporary support of the Facility during replacement or repair of the Highway Structure.


17-229 C.M.R. ch. 210, § 13

The following state regulations pages link to this page.

State regulations are updated quarterly; we currently have two versions available. Below is a comparison between our most recent version and the prior quarterly release. More comparison features will be added as we have more versions to compare.