18.7.230 ATTACHMENT TO HIGHWAY STRUCTURES
(1) For existing attachments:
(a) Attachments to existing structures in
place prior to
the
effective date of these rules are considered to be in compliance with this
rule, provided:
(i) The owner shall inspect the attachment
annually and shall repair any deficiencies. The owner shall maintain a record
of the inspections.
(ii) If the attachment is not currently
permitted by a structure attachment permit, the owner shall submit an application
for a permit and drawings to the appropriate district office for approval under
these rules within six months of the effective date of these rules.
(2) For proposed attachments to existing
structures:
(a) Where it is feasible and reasonable to
locate utility facilities elsewhere, attachment to highway structures will not
be allowed. Where other locations create undue hardship for the installation of
the facility, consideration will be given to attaching the utility facility to
a highway structure. The following conditions will apply:
(i) All utility facilities attached to
structures shall be attached as provided in this rule unless written approval
to do otherwise is granted by the department's bridge engineer.
(ii) Attachments to structures shall be
inspected by the owner at least once per year and the owner shall repair any
deficiencies immediately. Records of the inspections shall be maintained by the
owner for a minimum of three years.
(iii) Attachment to longitudinal structures on a full control access facility
system generally will not be permitted except to exclusively serve a highway
facility. Attachments to existing structures crossing the full control access
facility will be considered on a case-by-case basis.
(iv) The attachment method shall conform to engineering standards for
preserving the highway, its safe operation, maintenance and appearance.
(v) Attachment of a utility facility will
not be permitted unless the structure can support the additional load, and
accommodate the utility facility without
compromising highway user safety and convenience, and its attachment
does not impair bridge inspection or maintenance.
(vi) Manholes will not be allowed in the driving lanes of a bridge deck. Where the structure has a minimum shoulder
width of 3.048 meters (10 feet) , manhole access through the deck in the
shoulder area may be allowed within the discretion of the department.
(vii) The utility attachment will be installed on the bridge in a manner which
will not reduce the vertical clearances above river, stream, pavement or top of
a rail.
(viii) Utility attachments to the outside
of a structure that is located within 402.336 meters (440 yards) of a residential
structure, park, fishing access site, or other recreational facility will not
be permitted. A residential structure is any go building intended for human
occupancy, including businesses. This provision may be waived by the district
administrator if
the
utility can demonstrate the provision will place an economic hardship on the
utility and that the design and attachment of the facility will not detract
from the aesthetics of the structure. In other areas where, in the opinion of
the district administrator, bridge aesthetics are not a particular concern, a
utility may be attached to the outside of the structure. Utilities attached to
the outside of the structure will be on the downstream side.
(ix) Utility facilities shall be firmly attached to the structure and where
necessary padded to eliminate noise and abrasion due to vibrations caused by
wind or traffic.
(x) The installation of a utility through the
abutment or wing wall of an existing structure shall not be permitted.
(xi) In
locations where a utility attached to a structure is carried beyond the back of
the abutment, the utility shall curve or angle out to its proper alignment
outside the roadbed area within the shortest possible distance from the
abutment.
(xii) So
long as utility facilities comply with the other conditions set forth in these
rules such a facility may be attached to structures by hangers or roller
assemblies suspended from inserts in the underside of the deck or from hanger
rods clamped to a flange of a superstructure member.
(A) Bolting through the deck or concrete beams
shall not be permitted.
(B) Welding of attachments to steel members or
bolting through such members shall not be permitted.
(C) The use of anchors driven using the
explosive type drilling force shall not be permitted.
(D) Drilling in prestressed concrete beams shall
not be permitted.
(E) Attachments of utilities facilities to
bridge handrail or guardrail or their anchorage systems shall not be permitted.
(F) Attachment of pipelines carrying deleterious
or corrosive substances shall not be permitted.
(xiii) The design of a utility attachment to a highway structure shall include
provisions acceptable to the department for lineal expansion and contraction
due to temperature changes. Line bends or expansion couplings may be used for
this purpose.
(xiv) Each proposed bridge attachment will be considered on a case-by-case
basis by the department.
(xv) Trenching in the vicinity of piers, bents or abutments shall be a sufficient
distance from footings to prevent undercutting or material from sloughing from
under the footing.
(xvi) An
application which involves the reduction of existing waterway area shall not be
permitted.
(xvii) Utilities attached to bridges shall not be maintained from the bridge deck
without the prior approval of the department's district engineer.
(xviii) Utility facilities shall not be attached to bridges on or eligible for listing
on the national register of historic
places
without written consent of the state historic preservation officer.
(xix) By
accepting the occupancy permit, the owner of the utility facility shall be
fully liable to the department, or others, for any damage to the structure, or
the surrounding environment, caused by the placement and use of the facility on
a highway structure. If the structure is damaged by the utility facility,
through negligence or otherwise, so that the structure can not be used by the traveling
public, then the utility must pay all costs to repair the structure, and
associated costs.
(xx) The
department shall not allow any new attachments to a highway structure by
petroleum, natural gas, or other products pipelines in seismically active areas
(those areas where the anticipated acceleration coefficients due to an
earthquake exceed 100 of gravity) unless the structure has been retrofitted or
built in conformity to the department's seismic requirements since January 1,
1992. The department may waive this requirement if the department determines
that the structure is adequate for the seismic area within which it is located.
(3) For proposed attachments to new bridge structures:
(a) Where the department plans to construct a new structure, the design of the
structure will, upon request of a utility company, be reviewed by the
department's bridge bureau for accommodation of existing or proposed utility
installations consistent with the requirements set forth herein. The utility
company may be required to reimburse the state for additional design and
construction costs associated with accommodating the utility facility on the
new structure.
(b) Installation of a utility facility on a new structure shall be coordinated with
the bridge construction so as not to interfere with the operations of the
highway contractor.
(c) The
applicant shall submit complete plans and specifications of the proposed
installation, including the weight per lineal meter (foot) and detail drawings
to the department prior to the department's completion of plans and
specifications for the proposed structure.
(d) Utility facilities may be installed through free standing bridge abutments, but
shall not be permitted through abutments or bents that are expected to move as
the thermal expansion and contraction affects the bridge. The hole created in
the bridge abutment must be of the minimum size necessary to accommodate the
utility and it shall be sleeved to permit relative movement between the
abutment and utility.
(4) For pipelines:
(a) At the option of the utility, pipelines must be attached to a
highway structure by one of the following methods:
(i) The
carrier line shall be encased throughout the length of the structure and the
casing shall be carried beyond, but not through, the bridge abutments and shall
be effectively opened or vented at each end. The casing shall be designed to
withstand the same internal pressure as the carrier pipe; or
(ii) The
carrier line may be attached to the structure unencased using the following
design factors:
Class Location 1 0.50
Class Location 2 0.40
Class Location 3 0.33
Class Location 4 0.27
The
design factor specified shall be obtained in accordance with the equations set
forth in 49 CFR 192 by any combination of wall thickness and/or pipe yield
strength that will provide the required design factors. If the design factor is
obtained by increasing steel strength, the utility shall provide certification
at the time of installation to the department that the pipe, in fact, meets the
strength requirements in the design calculations.
(b) The
carrier pipe shall be pressure tested before start-up in accordance with
the latest edition of applicable industry codes, as well as the applicable
statutes and regulations.
(c) The
attachment shall be designed to prevent any discharge from damaging the
structure or reaching the waterway in the event of a rupture. That capability
shall be demonstrated to the satisfaction of the department's bridge engineer
prior to approval of the attachment.
(d) Pipelines using bridge members to resist
forces generated by fluids in motion shall not be permitted.
(e) The
following information shall be included in the application: outside diameter,
inside diameter, pipe material, actual working pressure, substance carried,
type of coating, and any other information requested by the department.
(f) Pipelines attached to highway structures
shall be electrically isolated from the structure.
(g) Pipelines shall be attached to provide sufficient clearance for convenience and
safety during maintenance and repair of the structure or other utility
attachments on the structure. The pipeline shall be located to minimize the
possibility of damage from traffic. Pipelines shall include the capability to
allow for expansion and contraction of the structure and the pipeline.
(5) For power and communication lines:
(a) Electric power and communication conductors attached to a highway structure
shall be insulated from the structure, and carried in protective conduit or
pipe throughout the structure. Exposed metallic conduit shall be grounded on
each end. Where metallic conduit is installed within two meters (seven feet) of
any metal parts of the structure which are readily accessible, including, but
not limited to, railings, platforms, or stairs, the metallic conduit shall be
bonded to the metal parts of the structure. When bonding, all sections of the
structure shall be bonded to the metallic conduits.
(b) Electrical power and communication lines
shall be attached to provide sufficient clearance for convenience and
safety
during maintenance and repair of the structure or other utility attachments on
the structure. The conduit shall be located to minimize the possibility of
damage from traffic. Conduits shall allow for the expansion and contraction of
the structure.
(c) Attachments shall comply with the national
electrical safety code and applicable regulations.
(d) Metallic conduit attached to structures that are cathodically protected shall
meet all of the above requirements and shall not adversely affect the cathodic
protection of the structure, i.e., insulate the conduit from the soil and use
anodes at each end for grounding. Method to be used shall be approved by the
department's bridge engineer on a case by case basis.
(6) Aerial
power or communication lines will not cross over bridges where it is possible
to avoid such installations. A minimum vertical clearance of 7.62 meters (25
feet) from the top of the bridge rail will be maintained. A horizontal
clearance of 7.62 meters (25 feet) will be maintained from the neat lines of
the structures.
(7) For attachment materials:
(a) All
attachments to structures shall be constructed from durable materials designed
for long service life and be free from routine servicing or maintenance. All
materials shall conform to current applicable industry specifications and
codes.
(b) All steel materials used in attaching a
utility conduit to a structure shall be stainless or galvanized.
(c) Materials used for attaching a utility facility to the structure shall be
compatible with the structural material to eliminate the possibility of
corrosion.
History: Sec. 60-3-101 and 60-4-402 MCA; IMP, Sec. 60-3-101 and 60-4-402 MCA; Eff. 12/31/72; AMD, 1995 MAR p. 854, Eff. 5/12/95.