| (D) Unencasement.
(i) Where encasement is not employed, the utility shall
show that the welded steel carrier pipe will provide sufficient strength
to withstand the internal design pressure and the dead and live loads
of the pavement structure and traffic. Additional protective measures
must include:
(I) heavier wall thickness, higher factor of safety
in design, or both;
(II) adequate coating and wrapping;
(III) cathodic protection; and
(IV) the use of Barlow's formula regarding maximum
allowable operating pressure and wall thickness, as specified in 49
CFR §192.105.
(ii) Shallow anode bed types exceeding 48 inches in
width may not be used in the department's right of way. All others
must have a depth of coverage of at least 36 inches. Deep well anode
beds of up to 60 inches in diameter are acceptable. Rectifier and
meter loop poles shall be placed at or near the right of way line.
(iii) The minimum length of the additional protection
is the same as that required for an encased crossing.
(iv) The district may allow existing lines under low-volume
highways to remain in place without encasement or extension of encasement
if they are protected by a reinforced concrete slab or equivalent
protection or if they are located at a depth of five feet under the
pavement structure and not less than four feet under a highway ditch.
(E) Vents. Vents shall be installed at both ends of
an encasement, regardless of length, with a marker on at least one
end. Vents shall be placed at the right of way line immediately above
the pipeline, situated so as not to interfere with highway maintenance
or be concealed by vegetation. The utility's name, address, and emergency
telephone number shall be shown on each vent marker.
(F) Aboveground appurtenances. Except for vents, pipeline
markers, and gas rectifiers, above ground appurtenances are prohibited
within department's right of way.
(c) Water lines.
(1) Material type. All material types used for water
lines shall conform to American Water Works Association, applicable
local requirements, and 30 TAC §290.44(a) (relating to Water
Distribution).
(2) Depth of cover. The minimum depth of cover is 36
inches from the lowest point of grade for longitudinal utility facilities,
and 60 inches from the lowest point of grade for all crossings.
(3) Encasement. Water lines crossing under paved highways
shall be placed in an encasement pipe within the department's right
of way. Existing water lines that are 24 inches or greater in diameter
may be allowed to remain unencased under the pavement of new low volume
highways, provided that the depth and all other requirements of 30
TAC §290.44 are met.
(4) Manholes. The width dimensions of manholes may
not be larger than is necessary to hold equipment involved and to
meet safety standards for maintenance personnel. The maximum inside
diameter of the manhole chimney may not exceed 48 inches. The outside
diameter of the manhole chimney at the ground level may not exceed
36 inches.
(5) Aboveground appurtenances.
(A) Fire hydrants and valves. When feasible, fire
hydrants and blow-off valves shall be located at the right of way
line. Fire hydrants may not be placed in the sidewalk or any closer
than five feet from the back of the curb. Valve locations shall be
placed so as not to interfere with maintenance of the highway.
(B) Water meters. Individual service meters shall be
placed outside of the department's right of way. Master meters for
a point of service connection may be placed in a manhole with a maximum
width of 48 inch inside diameter. If additional volume is required,
a manhole with a neck of 60-inch depth shall be used.
(d) Non-potable water control facilities.
(1) Applicability. This subsection applies to agricultural
irrigation facilities, water control improvement districts, municipal
utility districts, flood control districts, canals, and similar non-potable
water control facilities.
(2) Depth of cover. The minimum depth of cover, regardless
of type of pipe used, is 36 inches for longitudinal utility facilities,
and 60 inches from the lowest point of grade for all crossings.
(3) Encasement. All non-potable water control lines
crossing under paved highways shall be encased. At the district's
discretion, encasement may be omitted under center medians and outer
separations that are more than 76 feet wide.
(4) Location and design requirements. Longitudinal
buried pipe facilities installed within the right of way must conform
with §21.41(c) of this subchapter (relating to Overhead Electric
and Communication Lines), consistent with the clearances applicable
to all roadside obstacles. Open ditch facilities may not be installed
longitudinally within the department's right of way. Aboveground appurtenances
within the horizontal clearance of the highway facility are prohibited.
(5) Levee/ditch travel road location. Coordination
with and approval by the district is required where levee/ditch travel
roads intersect the highway.
(e) Sanitary sewer lines.
(1) Material type. All material types used for sanitary
sewer lines must conform to applicable provisions of 30 TAC Chapter
217 and applicable local requirements.
(2) Depth of cover. The minimum depth of cover for
gravity lines is 30 inches and not less than 18 inches below any pavement
structure. The minimum depth of cover for pressurized sanitary sewer
lines is 60 inches for crossings and 36 inches for longitudinal utility
facilities.
(3) Encasement. All crossings of paved highways within
the right of way shall be encased. At the district's discretion, the
district may exempt the encasement requirement under center medians
and outer separations that are more than 76 feet wide.
(4) Manholes. Manholes serving sewer lines up to 12
inches shall have a maximum inside diameter of 48 inches. For lines
larger than 12 inches, the manhole inside diameter may be increased
an equal amount, up to a maximum diameter of 60 inches. Manholes
for large interceptor sewers shall be designed to keep the overall
dimensions to a minimum. The outside diameter of the manhole chimney
at the ground level may not exceed 36 inches.
(5) Lift stations. Lift stations and pump stations
for sanitary sewer lines shall be located outside of the department's
right of way.
(f) Electric lines Lines.
(1) Depth of cover for longitudinal placement. All
underground electric lines placed longitudinally within the right
of way may be installed by direct bury at depths equal to or greater
than 48 inches.
(2) Depth of cover for crossings. The minimum depth
of cover for underground electric lines is 60 inches below the lowest
point of the crossed grade.
(3) Encasement. Electric lines crossing the roadway
shall be encased in high-density polyethylene(HDPE) or comparable
material with a strength greater than or equal to ductile iron, with
satisfactory joints, or materials and designs that provide equal or
better protection of the integrity of the highway system and resistance
to damage from corrosive elements to which they may be exposed. The
lines shall be buried a minimum of 60. Encasement shall be provided
as outlined in this section.
(4) Installation. The utility facility shall be located
as set forth in §21.37(b) of this subchapter (relating to Design).
(5) Aboveground appurtenances.
(A) Aboveground appurtenances installed as part of
an underground electric line shall be located at or near the right
of way line, and may not impede highway maintenance or operations.
(B) Structures that are larger in plan view than single
poles may be placed on the right of way if:
(i) the installation does not hinder highway maintenance
operations;
(ii) the housing is placed at or near the right of
way line;
(iii) the installation does not reduce visibility and
sight distance of the traveling public;
(iv) the dimensions of the housing are minimized, particularly
where the need to allow space for highway improvement or accommodation
of other utility lines is apparent;
(v) the outside width, length (longitudinal with respect
to the right of way), and height dimensions of the aboveground portion
of the housing do not exceed 36 inches, 60 inches, and 54 inches,
respectively;
(vi) the supporting slab does not project more than
three inches above the ground line, nor extend more than 12 inches
on either side of the housing structure; and
Cont'd... |
