UndergroundElectrical Distribution
GUIDELINES
Effective January 1, 2005
INTRODUCTIONGuidelines in this booklet will help the Developer install proper and safe underground electric facilities in developments in the Allegheny
Power service area. The section on communication/coordination is very important. It tells how to work with the Company to avoid
construction problems and delays. Please review the guidelines contained in this booklet prior to starting your project. If you have any
questions not answered in this booklet, please call the Company’s Customer Service Center at 1-800-Allegheny (1-800-255-3443).
DEFINITIONS
Company: “Allegheny Power” and the areas it serves in Maryland, Ohio, Pennsylvania, Virginia, and West Virginia.
Customer: Any present or prospective user of the Company’s services.
Developer: Party responsible for constructing and providing planned property improvements such as streets, sidewalks, and
utility-ready lots. A Developer can be a contractor, builder, excavator, electrician, customer, etc. improving property for electric
utility service.
Residential Development: Planned project, which is developed for electric service set out in a recorded plot plan of one or more
lots for construction of single-family residences, detached or otherwise, mobile homes, townhouses, or apartments, all of which are
intended to be permanent installations.
Industrial/Commercial Development: Planned project, which is developed for electric service set out in a recorded plot plan of
one or more lots for construction of industrial or commercial occupancies or structures, all of which are intended to be permanent
installations.
Primary: Distribution line that delivers higher voltage electricity to transformers and other equipment.
Secondary: Distribution line that delivers lower voltage (less than 600 volts) electricity from transformer to a pedestal.
Service Lateral: Electric supply line from transformer or pedestal to a building or structure.
Cable: Insulated electrical conductors for use on the Company’s underground primary, secondary and service laterals.
Junction: A termination or connection point for primary cables.
Pedestal: A termination or connection point for secondary or service lateral underground cables. The term “pedestal” referenced
in this booklet does not include customer owned metering pedestals.
Work Request Number: A unique number assigned by the Company for the purpose of designing, tracking, constructing and
billing a project.
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GUIDELINES INDEX
I. DEVELOPMENT GUIDELINES
A. Plan Layout ............................................................................................................................................................. 3
B. Location of Company Facilities ....................................................................................................................... 3
II. CONSTRUCTION GUIDELINES
A. Site Preparation .................................................................................................................................................... 4
B. General Installation ............................................................................................................................................. 4
C. Trenching Standards .......................................................................................................................................... 4
D. Conduit Standards .............................................................................................................................................. 4
E. Backfill Standards ................................................................................................................................................ 5
F. Communication/Coordination with Company ........................................................................................ 5
EXHIBIT INDEX
1. Standard Distribution Layout ....................................................................................................................................... 6
2. Typical Townhouse Layout ............................................................................................................................................ 7
3. Single-Phase Transformer Site Detail ........................................................................................................................ 8
4. Three-Phase Transformer Pad Detail (75 to 500 kVA) .......................................................................................... 9
5. Three-Phase Transformer Pad Detail (750 to 2500 kVA) .................................................................................. 10
6. General Notes for Three-Phase Pad Foundations .............................................................................................. 11
7. Junction Detail ................................................................................................................................................................ 12
8. Pedestal Detail ................................................................................................................................................................ 13
9. Typical Trenching Detail .............................................................................................................................................. 14
10. Backfilling Specifications ............................................................................................................................................ 15
11. Conduit Specifications ................................................................................................................................................. 16
12. Typical 320 Amps or Less Underground Service Installation ........................................................................ 17
13 . Typical Underground Mobile Home Service ....................................................................................................... 18
14. Temporary Service Details .......................................................................................................................................... 19
Company and Underground Utility Lines Locating Telephone Numbers ............................................ Back Cover
I. DEVELOPMENT GUIDELINES
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A. PLAN LAYOUT
1. The Developer shall contact the Company’s Customer
Service Center concerning the project, at which time a
work request number will be issued. A Lines
Engineering Designer at the local service center must
receive an approved, recorded lot plan drawing with
all lot front footages and arc distances shown, and
profiles of proposed streets showing the location of
curbs, sidewalks, and all other underground utilities.
This information should be provided at least twelve
(12) weeks prior to the date service is required.
2. If the project is to be developed in phases, the
Developer shall provide a master plan drawing, which
details the total area to be developed, including the
location of all future streets and a proposed schedule
for construction.
B. LOCATION OF COMPANY FACILITIES
1. The standard location of Company underground
facilities in residential developments is front lot line
with each dwelling served by a separate service.
2. Easements required for Company underground
facilities are a minimum of 10 feet in width. See
Exhibit 1 for a typical residential easement layout.
Along front lot lines, the easement extends 10 feet
into private property from the street right-of-way.
Along side lot lines, the 10 foot easement is split
evenly between the adjacent lots (5 feet on each lot).
The right-of-way agreement covering the use of the
easement is obtained from the property owner and
is legally recorded against the development as
permanent record by the Company. Right-of-way
agreements shall be properly executed prior to selling
any lots.
3. The meter socket for a residential structure shall be
located within 15 feet of the corner nearest the
service lateral conduit stub as shown in Exhibit 1.
The Company reserves the right to designate the
exact meter location for all buildings and structures.
4. Company facilities for Commercial and Industrial
developments shall be located to best serve the
structure and may require additional easement width.
5. For Commercial and Industrial structures, consult the
Company for meter socket location and metering
requirements.
II. CONSTRUCTION GUIDELINES
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A. SITE PREPARATION
1. The Developer shall receive Company approved
electrical layout design drawing(s) prior to beginning
trenching or transformer, junction, and pedestal site
preparation.
2. The Developer shall provide site preparation in the
following manner prior to the installation of
Company’s facilities:
a. Grade all underground Company easements and
street rights-of-way within 6 inches of the final
grade.
b. Provide a clear level area, free of obstructions at
final grade, for all transformers, junctions, and
pedestals as per Exhibits 3, 4, 5, 6, 7 and 8. For
installation of manholes or vaults, consult
Company for details.
c. Identify all required boundaries and provide lot
corner pins and lot number stakes for all lots.
d. Provide radius stakes for all curved portions of
streets where Company cables will be installed.
e. Provide an all-weather-access road through the
development to all of the Company’s existing and
proposed facilities.
B. GENERAL INSTALLATION
1. The Developer shall provide all trenching and
backfilling and also provide and install all required
conduits. Pedestals, warning tape, and sleeves for
junctions shall be furnished by the Company and
installed by the Developer. Single-phase transformer
pads are provided and installed by the Company.
Three-phase transformer foundations are provided
and installed by the Developer.
Virginia Only – For a planned residential
development of five or more lots according to Tariff
Schedule E, Plan C, the Company will provide and
install all necessary facilities for electric service
including trenching and backfilling, conduit
installation, warning tape, transformer pad site
preparation, junctions and pedestals.
2. All trenching and backfill shall also comply with local
and state regulations.
3. For street lighting applications in conjunction with
the development, consult the Company for details.
C. TRENCHING STANDARDS
1. The trench is to be excavated at the location indicated
by the Company’s approved electrical design
drawing(s). In certain instances, the Company may
choose to field stake the trench location at the site.
2. The Company cannot accept responsibility for
trenching done prior to obtaining Company approved
electrical design drawing(s) and/or field indication of
the trench location.
3. The Developer must notify the Company of the
schedule for trenching and backfilling to coordinate
cable installation by the Company.
4. The trench shall be excavated to the specification
shown in Exhibit 9.
5. The trenching specifications outlined in Exhibit 9 are
those of the Company and not necessarily those of
other utilities. The Developer shall therefore
coordinate the occupancy of the trench with the
other utilities. The Company will normally agree to
slight modifications of the trench provided the
dimensions shown are maintained or exceeded.
6. In any case where trench depth must exceed four feet,
approval must be obtained from the Company.
7. State laws require that persons planning to excavate
shall mark the area to be excavated with white paint
and call the telephone numbers on the back cover for
that state for assistance in locating and marking
underground facilities. This call shall be made at least
48 hours (72 hours in Pennsylvania), not including
weekends and holidays, in advance of the planned
excavation.
D. CONDUIT STANDARDS
1. USE OF CONDUIT
a. The Developer shall provide and install the
conduit system to provide proper protection, in
accordance with the layout provided by the
Company’s approved electrical design drawing(s).
The Company must approve any changes to the
layout. The Company reserves the right to
approve the type of conduit to be used prior to its
installation.
b. Conduit(s) are required for all cables. The
Company will specify the size and number of the
conduits to be installed. The conduit(s) shall be
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furnished and installed by the Developer.
Additional conduits may be required for the
occupancy of the other utilities.
c. When conduits are required by the Company for
other than the Developer’s needs, the Company
will provide and Developer shall install conduits.
2. COMPANY APPROVED CONDUIT
a. Conduit shall be electrical grade, rigid, non-
metallic and of standard trade size (3”, 5”, or 6”
diameter). For 3” and 5” conduit, the approved
types are Schedule 40 PVC or Type II PVC (DB120
or DB60). For 6” conduit, the only approved type
is Schedule 40 PVC. See Exhibit 11.
b. Conduit for street lighting circuits shall be 1 ½”
Schedule 40 or Type II PVC (DB120 or DB 60).
3. CONDUIT INSTALLATION
a. Conduit shall be run in a straight and level path.
There shall be no abrupt changes in conduit
direction (elevation or sideways) except for bends
at pad mounted equipment and for turning-out
service lateral conduits to lots. Spacers shall be
used where necessary to maintain direction,
plumb or spacing of conduit.
b. All joints are to be cemented and both ends of
the run are to be capped to ensure the conduit
remains clean and dry. The ends shall be marked
at a point above final grade (see Exhibit 1, Note 2).
c. A ¼” high strength pull rope (nylon or
polypropylene) shall be installed by the
Developer for Company use. Low strength rope,
twine or string is unacceptable. The Developer
shall correct any failure of the pull rope.
E. BACKFILL STANDARDS
1. The Developer shall provide Company approved
backfill to cover and protect underground distribution
facilities. See Exhibit 10 for backfill specifications.
2. The Company reserves the right to examine and
approve the backfill before its use and reject any
materials that are not satisfactory for the purpose of
backfill.
3. A warning tape will be provided by the Company and
shall be installed by the Developer to the
specifications shown in Exhibit 9.
4. Electronic markers, if provided by the Company, shall
be installed by the Developer in the locations as
specified by the Company.
5. Backfill is to be installed in the trench (as detailed in
Exhibit 9) in such a manner that the conduit is not
damaged. Backfill must be tamped to avoid settling.
Settling of the trench and road crossings is the
Developer’s responsibility.
F. COMMUNICATION/COORDINATION WITH THE COMPANY
1. The Developer shall reference the Work Request
number in all correspondence with the Company.
2. The Developer shall coordinate a construction
schedule with the Company concerning the
installation of the distribution facilities. See back
cover for the local Company service center trench
inspection telephone numbers.
3. Communication between the Developer and
Company will be necessary for the following items in
order to minimize construction problems and delays:
a. Any modifications or revisions to the approved
design should be reviewed and approved by the
Company prior to implementation.
b. Notification of conduit installation schedules shall
be given to the Company as soon as possible
(minimum one week) prior to trenching for the
purpose of scheduling trench and conduit
inspection and cable installation.
c. Any other problems or questions regarding the
project shall be reviewed with the Company.
4. The Developer may be required to pay additional
charges for Developer requested design changes, or
for return trips or other occurrences that cause the
Company additional expense.
Exhibit 1 STANDARD DISTRIBUTION LAYOUT
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Exhibit 2 TYPICAL TOWNHOUSE LAYOUT
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Exhibit 3 SINGLE-PHASE TRANSFORMER SITE DETAIL
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Exhibit 4 THREE-PHASE TRANSFORMER PAD (75 TO 500 kVA)
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Exhibit 5 THREE-PHASE TRANSFORMER PAD (750 TO 2500 kVA)
Exhibit 6 GENERAL NOTES FOR THREE-PHASE PAD FOUNDATIONS
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Exhibit 7 JUNCTION DETAIL
Exhibit 8 PEDESTAL DETAIL
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NOTES:1. PROVIDE ALL TRENCHING AND BACKFILLING THAT IS REQUIRED FOR THE INSTALLATION OF THE
UNDERGROUND DISTRIBUTION FACILITIES (EXCEPT IN VIRGINIA WHEN TARIFF SCHEDULE E, PLAN C, APPLIES).
2. EXCAVATE TRENCH IN THE LOCATION INDICATED BY THE COMPANY’S APPROVED ELECTRICAL LAYOUTDRAWING(S) OR FIELD STAKES.
3. EXCAVATE TRENCH TO THE DIMENSIONS SHOWN ABOVE. PRIMARY, SECONDARY AND SERVICE LATERALCONDUITS MAY BE INSTALLED IN THE SAME TRENCH, PROVIDED THE PRIMARY TRENCH DIMENSIONS ARE USED.
4. THE DEVELOPER SHALL NOTIFY THE COMPANY OF THE SCHEDULE FOR TRENCHING AT LEAST ONE WEEKPRIOR TO THE OPENING OF THE TRENCH FOR THE PURPOSE OF SCHEDULING TRENCH INSPECTION ANDCABLE INSTALLATION.
5. THE BOTTOM OF THE TRENCH MUST BE FREE OF ROCK, CINDERS, OR SHARP OBJECTS. A 2” BED OFAPPROVED BACKFILL BELOW THE CONDUIT (SEE EXHIBIT 10, PART 2.A.) AND 6” OF APPROVED BACKFILLCOVER ABOVE THE TOP OF THE CONDUIT (SEE EXHIBIT 10, PART 2.A.) ARE REQUIRED TO PREVENT CONDUITDAMAGE. APPROVED BACKFILL MUST MEET THE COMPANY’S SPECIFICATIONS. THE REMAINDER OF THETRENCH SHOULD BE BACKFILLED TO GRADE USING NATIVE BACKFILL (SEE EXHIBIT 10, PART 2.B.). ALLBACKFILL SHOULD BE COMPACTED TO AVOID SETTLING.
6. THE DEVELOPER SHALL COORDINATE THE OCCUPANCY OF THE TRENCH WITH OTHER UTILITIES. CONSULTTHE COMPANY’S LINES ENGINEERING DESIGNER IF THE TRENCH DEPTH MUST BE MORE THAN 4 FEET.
7. NO SEPARATION BETWEEN ELECTRIC CABLES AND TELEPHONE OR CATV FACILITIES IS REQUIRED BYTHE COMPANY WHEN LINES ARE INSTALLED IN CONDUIT. THE DEVELOPER SHOULD DETERMINE THESEPARATION REQUIRED BY THE TELEPHONE OR CATV COMPANIES, IN WHICH CASE THE POWER CABLEDEPTHS SHOWN ABOVE MAY HAVE TO BE INCREASED TO MAINTAIN SEPARATION.
8. SEPARATION BETWEEN ELECTRIC CABLES AND GAS, WATER OR SEWER LINES SHALL BE 12” MINIMUM.GREATER SEPARATION SHALL BE MAINTAINED WHERE PRACTICAL. LOCAL GAS, WATER, AND SEWERCOMPANIES MAY REQUIRE GREATER SEPARATION. THIS SHOULD BE DETERMINED IN ADVANCE BY THEDEVELOPER.
9. INSTALL IDENTIFICATION TAPE AS SHOWN IN THE EXAMPLES. THE IDENTIFICATION TAPE IS PROVIDED BY THECOMPANY.
10. A 1/4” HIGH STRENTH PULL ROPE (NYLON, OR POLYPROPYLENE) SHALL BE INSTALLED BY THE DEVELOPERFOR THE COMPANY’S USE. LOW STRENGH TWINE OR STRING IS UNACCEPTABLE. ANY FAILURE OF THISPULL ROPE SHALL BE CORRECTED BY THE DEVELOPER.
Exhibit 9 TYPICAL TRENCHING DETAIL
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Exhibit 10 BACKFILL SPECIFICATIONS
1. GENERAL
A. This specification covers standards for approved backfill to be used to protect underground distribution conduitfrom damage in the trench.
B. The Company reserves the right to examine and approve the backfill before its use and to reject any material whichdoes not meet the standards listed in this Exhibit.
C. All backfill shall be generally smooth, round in shape, and free of any sharp or pointed edges.
2. COMPANY APPROVED BACKFILL
A. Backfill 2” below and 6” above the top of any conduit shall be stone dust, rock-free earth, or topsoil with no stoneslarger than 1½” in diameter permitted.
B. Backfill from 6” above the top of any conduit to final grade shall be native backfill containing no large rock.
3. BACKFILL INSTALLATION
A. The bottom of the trench must be free of rock, cinders, or sharp objects. A 2” bed of approved backfill below theconduit and 6” of approved backfill cover above the top of the conduit are required to prevent conduit damage.Approved backfill must meet the specifications in number 2 above. The remainder of the trench should be backfilledto grade using native backfill. All backfill should be compacted to avoid settling. Backfilling should be coordinatedwith other utilities occupying the trench.
B. See Exhibit 9 for additional details on trenching and backfilling.
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Straight Sections
Type Diameter Specification PVC: Straight Section * 1.5" Type II Direct Bury or Schedule 40
PVC: Straight Section 3" Type II Direct Bury or Schedule 40
PVC: Straight Section 5" Type II Direct Bury or Schedule 40
PVC: Straight Section 6" Schedule 40 Only
Elbow and Bends
Type Diameter Radius Specification PVC: 22.5, 45, & 90 Degree Bends * 1.5" 18" Type II Direct Bury or Schedule 40
PVC: 90 Degree Bends ** 3” 30” Type II Direct Bury or Schedule 40
PVC: 22.5, 45, & 90 Degree Bends 3" and 5" 36" Type II Direct Bury or Schedule 40
PVC: 22.5, 45, & 90 Degree Bends 6" 48" Schedule 40 Only
Service Riser
Type Diameter Radius SpecificationPVC 3" 30" Schedule 80
* 1.5" conduit to be used for streetlight systems only.** 3” schedule 80 bends, 30” radius to be used for service riser.
Exhibit 11 CONDUIT SPECIFICATIONS
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Exhibit 12 TYPICAL 320 AMP OR LESS UNDERGROUND SERVICE INSTALLATION
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Exhibit 13 TYPICAL UNDERGROUND MOBILE HOME SERVICE
Exhibit 14 TEMPORARY SERVICE DETAILS
TEMPORARY UNDERGROUND SERVICE SUPPORT AT THE TRANSFORMER
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Stock # 090900
CUSTOMER SERVICE CENTER
TELEPHONE ....................................................................................................... 800-ALLEGHENY (800-255-3443)
FAX OR E-MAIL APPLICATIONS FOR SERVICE
FAX ............................................................................................................................................................ 800-453-9366
E-MAIL ............................................................................................... [email protected]
LOCAL SERVICE CENTER TRENCH INSPECTION TELEPHONE NUMBERS
PENNSYLVANIA: STATE COLLEGE .................................................................... 814-231-5303 (VOICE)
MARYLAND: CUMBERLAND ...................................................................... 301-759-5753 (FAX)
FREDERICK ............................................................................. 301-694-4480 (VOICE)
301-694-4479 (FAX)
MT. AIRY .................................................................................. 301-829-7020 (VOICE)
OAKLAND............................................................................... 301-533-3303 (FAX)
THURMONT ........................................................................... 301-271-5905 (VOICE)
301-271-5934 (FAX)
WILLIAMSPORT .................................................................... 301-582-5207 (VOICE)
WEST VIRGINIA: MARTINSBURG ..................................................................... 304-267-3208 (VOICE)
NOTE: IF YOUR LOCAL SERVICE CENTER IS NOT LISTED, PLEASE CALL THE CUSTOMER SERVICE
CENTER TELEPHONE NUMBER AT THE TOP OF THIS PAGE.
UNDERGROUND UTILITY LINES LOCATING SERVICE TELEPHONE NUMBERS
PENNSYLVANIA: “PA ONE-CALL” .......................................................................... 1-800-242-1776
MARYLAND: “MISS UTILITY” ........................................................................... 1-800-257-7777
OHIO: “OUPS” ......................................................................................... 1-800-362-2764
VIRGINIA: “MISS UTILITY” .......................................................................... 1-800-552-7001
WEST VIRGINIA: “MISS UTILITY” ........................................................................... 1-800-245-4848
COMPANY AND UNDERGROUND UTILITY LINESLOCATING SERVICE TELEPHONE NUMBERS