Easement Control Electrical Pole Inspections

2. Scope
This procedure provides guidelines covering the management of electricity easements. It is
applicable to all electricity easements covering Power and Water underground and overhead
power lines.
3. Definitions
Controlled Activities are activities and developments that are acceptable provided the
conditions of use are agreed in writing by Power and Water beforehand.
Easement is an encumbrance on private land that gives Power and Water the right to use and
have access to the land for the purpose for which the easement is granted. It is noted on both
the Title and the Survey Plan, which shows the exact dimensions of the easement.
Permitted Activities are activities and developments that may be carried out within overhead
line easements without risk to personal safety or line integrity.
Prohibited Activities are activities or developments within an easement that cannot be
tolerated under any circumstances or at any time. If such activities or developments do occur,
Power and Water will require that they be discontinued or removed as appropriate.
4. Introduction
4.1 Purpose of an Easement
Wherever Power and Water assets such as overhead power lines or underground
cables cross private land it is necessary for Power and Water to have an assured right
of access to construct, inspect and maintain the asset. Easements are established to
safeguard these needs. Rules for the use of an easement by others are set up to
ensure the safety of persons within the easement and to protect Power and Water’s
plant.
This in turn ensures that the security and reliability of service to customers can be
maintained, and requires that Power and Water can restrict activities within the
easement to minimise the risk of personal injury and to retain unimpeded access.
Throughout this Policy references to overhead lines and cables include all associated
equipment such as substations, switch yards and distribution pillars.
4.2 Establishing an Easement
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1 NT Crown Lands Act 2000 Division 4
2 Land Titles Act 2007 Division 4
The need for an electricity easement arises when Power and Water is required to install
new plant to supply new customers or reinforce supply to existing customers and
cannot reasonably do so using public land. Most commonly, in new URD subdivisions,
pillars and substations are located on easements off the road reserve. The developer is
required to provide these at no cost to Power and Water.
Where it is necessary to install new network assets on private property, Power and
Water will approach private land owners affected by the proposal and seek easements
across the land.
If a land owner requests a change to the route or location, then these wishes will be
incorporated wherever practicable.
Wherever practicable, a valuation for the easement should be obtained from the Office
of the Valuer General. However, if the landowner refuses to grant an easement at the
value decided upon by the Valuer General, then consideration must be given to a
higher offer, or compulsory acquisition. The latter is generally a last resort, and legal
costs and time mean that the cost of this alternative is often very high.
Compensation amounts in excess of the Valuer General’s valuation should be referred
to the Manager Network Engineering.
On completion of these negotiations, the easement will be surveyed.
On receipt of the survey plan, the matter should be referred to the Office of the
General Counsel for registration of the easement and payment of the agreed amount.
If the line or cable is required to cross the land to supply the owner or occupier of the
land, then the granting of an easement shall be a condition of the supply of electricity
and all costs are borne by the applicant.
If the line or cable is to be installed to supply customers other than the land owner or
occupier then the owner may decline to grant an easement. In that event further
attempts should be made to find an alternative route. If no satisfactory alternative
route is found then Power and Water may invoke its powers of compulsory acquisition
to acquire the easement. This is not preferred and is a last resort.
An easement granted to or acquired by Power and Water is an easement in gross
within the meaning of the Crown Lands Act1 for leased Crown Land, and within the
meaning of the Land Titles Act2 for other land.
4.3 Easements and Change of Land Ownership
Where, for example, an overhead power line has been erected over Vacant Crown Land
(VCL) and that land is subsequently released for development, the prospective
developer is normally advised by DPE that a power line exists and that an easement
will be taken to cover it. The developer is then bound by the conditions set out in the
Development Permit and this Policy and is required to abide by them.
Where an easement already exists and the ownership of land changes, the easement is
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already registered as an encumbrance on the title and remains in full force.
Where an easement exists over a pastoral lease over which Native Title has been
granted, there is no effect on the easement.
If Power and Water wishes to construct a line across land over which Native Title has
already been granted, the only course open is to negotiate an easement, which is
within the power of the Native Title holders to grant.
Power and Water has no power of compulsory acquisition of an easement over land
covered by Native Title. For land that is the subject of a Native Title Claim, refer to the
Corporation’s Legal Counsel.
4.4 Effect on Land Use
To fulfil its purpose every easement must be kept clear for access, but some use is
permissible. The activities that are/are not permissible are detailed in Section 6.
Approval may be given for encroachments outside these Guidelines if it is considered
that the proposed use will not limit Power and Water access or cause hazards.
4.5 Relinquishing an Easement
Where an easement is no longer required, it may be relinquished with the approval of
the General Manager Power Networks.
Easements have value to both Power and Water and the property owner, and where
Power and Water paid the land owner for the original easement, relinquishment should
only occur where the land owner compensates Power and Water at a value agreed by
the Valuer General.
5 Safety in Electricity Easements
5.1 Introduction
Section 4 of this Policy describes the nature and purpose of easements along overhead
lines and underground cables in private property. Section 6 defines the dimensions of
the easements and lists various activities which are/are not acceptable within an
easement.
Many activities are permissible within easements without reference to Power and
Water, while others may only be undertaken with the written permission of Power and
Water, and then under controlled conditions.
5.2 Types of Hazards within Easements
There are two principal types of hazards within an easement, namely accidental contact
with live conductors, and induced or transferred voltages.
(a) Accidental Contact
The Electricity Reform (Safety and Technical) Regulations provide safe working
distances for overhead and underground lines. Failure to observe these
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clearances is an offence under the Regulations, and has the potential to cause a
serious accident.
The Work Health (Occupational Health and Safety) Regulations also provide
approach limits to overhead lines.
Guidance on measures required to maintain safety are detailed in Appendix A.
(b) Induced and Transferred Voltages
Overhead conductors carrying fault current produce an unbalanced
electromagnetic field, which will induce voltages in any conducting object
parallel to them. Under fault conditions it is possible for significant voltages to
be induced in nearby metallic structures, such as fences.
Earth faults will cause the earthing system to rise in potential above earth. A
fault some distance away may still cause local earthing systems to rise in
voltage appreciably – this is known as a “transferred” voltage. Line supports
may become momentarily energised by transferred voltages.
Under fault conditions hand-foot voltages can be experienced if touching a line
support. This is known as “touch” potential, and is potentially dangerous. Less
dangerous, but still of concern, is “step” voltages, caused by a voltage
“gradient” radiating out from line supports. Voltages of several kV per metre
have been measured, creating a possibility of an electric shock between a
person’s feet.
The potentially most dangerous situation is a “hand to hand” shock caused by
simultaneously touching conducting objects at different potentials. A nearby
fence or building which is not connected to the line is likely to be at a different
potential than the line support. A person simultaneously touching a pole and a
nearby unattached fence could be subjected to a significant voltage under fault
conditions. As a general rule, metallic structures within 2 metres of a line
support should be electrically connected to it, or insulated. All such situations
should be referred to the Manager Network Engineering.
Electrostatic effects are possible with higher voltage lines (e.g., 132,000 volt
transmission lines), while all power lines generate some EMFs (50 Hz electromagnetic
fields). These effects are not known to be hazardous, but may cause
concern to some people. Refer to the ARPANSA EMF standard for more
information on permissible electric and magnetic fields.
Precautions to be taken to avoid contact with, or the effects of, induced or
transferred voltages are discussed in Section 6.
6. Conditions of Use
6.1 General
The purpose of an easement is to safeguard Power and Water's right of access to
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construct, inspect and maintain an asset which stands on private property, and to
regulate the activities of others within the easement to ensure the safety of all people
and safe and reliable operation of the asset.
6.2 Easements for Overhead Lines
The needs related to overhead lines are:
♦ access for construction and inspection
♦ cleared space to prevent accidental contact with trees in high winds
♦ access for reconstruction or repairs where necessary.
Overhead lines need to be patrolled and inspected, often from Elevating Work Platform
(EWP) vehicles. During construction or major repairs such as pole replacement, even
larger vehicles, such as crane / borer vehicles, may be used to erect line supports.
The easement width needs to be sufficient to facilitate control of vegetation that is
potentially likely to contact conductors. Refer to Network Policy NP 013 Management
of Vegetation Near Overhead Power Lines.
Current Power and Water policy is based on the following easement widths:
Line Voltage (kV) Easement Width (metres)
0.400 8.0
11 10.0
22 10.0 to 20.0 ( depending
66 (single circuit) 25.0 to 35.0 ( on the type
132 (single circuit) 35.0 to 45.0 ( of construction
275 (single circuit) 50.0
For 66, 132 and 275kV lines, it is common to establish transmission “corridors” which
are designed to take two or more lines in ultimate configuration. Consequently, it is
often the case to find that single circuit lines have quite large easements, to cope with
future lines.
As well as securing access to the line, Power and Water has the responsibility of
keeping trees and other objects far enough from the wires to avoid accidental contact.
For this purpose there is a standard buffer zone within which trees will be felled or
trimmed as necessary and this is illustrated in Drawing Number S1-4-1-4 (see Appendix
A). In addition an area of 2 m radius around supporting guys will be cleared of all
vegetation.
6.3 Activities within Overhead Line Easements
Some activities and developments may be carried on within overhead line easements
without risk to personal safety or line integrity. These are classified as Permitted
Activities.
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Prohibited Activities cannot be tolerated under any circumstances or at any time. If
such activities or developments are found, action shall be taken to have them
discontinued or removed as appropriate.
Between these extremes are Controlled Activities that are acceptable provided the
conditions of use are agreed in writing by Power and Water beforehand.
It should be kept in mind that overhead line easements may need to be traversed at
any time by heavy vehicles for line maintenance or other work. A clear path must be
maintained to allow this access.
6.3.1 Permitted Activities
Activities which are permitted provided safe practices are observed are:
• agricultural grazing, planting and harvesting subject to the height
restrictions shown in Drawing S1-4-1-4.
• gardening including the planting of trees and shrubs within the limits
specified in Drawing S1-4-1-4.
• parking of vehicles below 4.0 m in height, including caravans which are not
occupied and have no power supply connected
• domestic recreation, but excluding those activities described in Section
6.3.3
• operation of mobile plant not capable of extension beyond 4.0 m in height
• storage of non inflammable materials up to a height of 4.0 m in height (or
2.5 m if they or their housing are climbable)
• erection of minor domestic equipment or non metallic fences up to 2.5 m in
height. All metallic components must be earthed correctly
• wherever fences are erected across easements, gates or removable panels
with a minimum width of 3.6 m must be provided to give access for plant
and machinery. Locks on gates must include a standard Power and Water
padlock.
6.3.2 Controlled Activities
The following activities may only be undertaken with the written consent of
Power and Water and then only under such controlled conditions as Power and
Water may specify. Any activities not listed and not permitted under Section
6.3.1 must be referred to Power and Water for written consent to proceed.
• earthworks, except as specified in Section 6.3.3
• operation of mobile plant capable of extension above 4.0 m in height
• erection of metallic fencing up to 2.5 m in height provided it is earthed
correctly
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• installation of irrigation equipment provided no part of the equipment
exceeds 4.0 m in height and no solid jet of water can come within 3.0 m of
line conductors. Water jets must be such that they cannot cause conductor
clashing.
• erection of electric fencing up to 2.5 m in height provided it does not pass
beneath the line
• installation of other services such as water, telephone etc. provided safe
working clearances are maintained and due consideration is given to the
risk of induced voltages
• construction of roads provided design clearances are maintained (see
Drawings S1-4-1-2 and S1-4-1-3)
• construction of dams and creation of bodies of water
• burning off or lighting of fires
• conduct of sporting and recreational activities which cannot, even by
misuse, constitute a hazard to the line or persons
Wherever controlled activities are approved but their implementation is
subsequently found to not comply with the terms of the approval, or create a
hazard or impediment, action shall be taken to rectify the situation.
6.3.3 Prohibited Activities
The following activities are prohibited in overhead line easements except under
the most extreme circumstances.
• camping
• construction of houses, out buildings, pergolas or other substantial
structures
• installation of fixed plant or equipment
• storage of flammable materials
• storage or use of explosives
• placing of garbage, refuse or fallen timber
• planting trees which will encroach upon the clearances specified in Drg S1-
4-1-4
• excavation within 5 m of any overhead line structure
• placing any obstruction within 5 metres of any part of a structure
• installation of a swimming pool or spa
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• placing of caravans for occupation
• attachment of anything to structures (except where fences need to be
bonded to a pole – see 5.2(b) above)
• flying kites or model aircraft
• flying aircraft, hang gliders, balloons etc.
• erecting fences greater than 2.5 m in height
6.4 Easements for Underground Cables and Associated Plant
The width of an underground cable easement is again dependent on voltage, but more
particularly on the space required for access by excavating and cable laying equipment
that will in many cases exceed the width required for the cables alone. Drawing
S2-2-6-17 shows the width of easement required for the access of cables to and from a
distribution substation, where the substation is set back from a property boundary
and/or access is required to an adjoining street. This width also applies to a general
run of cable across open ground for voltages up to and including 33 kV.
At voltages in excess of 33 kV the easement width will be determined by the number
and spacing of circuits and the separation of phases in a circuit comprising single core
cables. This can only be determined by individual circuit design but may be assumed
to be a minimum of 5 m.
Drawing S2-2-6-17 also shows the easement required to accommodate ground
mounted distribution substations and distribution pillars.
Underground cable 3 metres wide
Package substation 3.5 x 3.5 metres
Kiosk substation 3.0 x 7.0 metres
Low voltage URD pillar 1.0 x 1.0 metres
Low voltage fused pillar 2.0 x 2.0 metres
Ring Main Unit 3.5 x 2.5 metres (typically)
6.5 Use of Underground Cable Easements
6.5.1 Permitted Activities
Activities which are permitted within underground cables easements are:
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• domestic recreation
• planting of grass for lawns provided no tilling of the soil occurs to a depth
greater than 200 mm.
6.5.2 Controlled Activities
The following activities may only be undertaken with the written consent of
Power and Water and then only under such controlled conditions as Power and
Water may specify:
• earthworks
• storage of non inflammable materials
• parking of vehicles within weight limitations which will avoid cable damage
• operation of mobile plant within weight limitations which will avoid cable
damage
• excavation by hand or mechanised plant after due investigation by Power
and Water for cable locations
• reduction of ground cover over cables; in which event additional mechanical
protection shall be provided. Drawings S2-2-6-2 and S2-2-6-3 show
minimum required standards
• increasing ground cover within limits which will not adversely affect cable
ratings
• installation of structures spanning the easement provided a minimum 4 m
headroom is maintained below the structure to ground level
• installation of driveways across the easement and where protection can be
given for vehicle wheel loads
• installation of other buried services after due investigation by Power and
Water of cable locations
• erection of fences after due investigation by Power and Water of cable
locations
• planting of shallow rooted crops where the depth of tilling does not exceed
200 mm.
6.5.3 Prohibited Activities
The following activities are prohibited in underground cable easements:
• storage of flammable materials
• storage and use of explosives
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• planting of trees and shrubs
• construction of houses, out buildings or other substantial structures
• installation of fixed plant or equipment
• placing of garbage or fallen timber
• removal of artefacts or disturbance of significant sites within the meaning
of the Commonwealth Aboriginal and Torres Strait Islander Heritage
Protection Act 1984.
6.6 Activities around Distribution Substations and Service Pillars
6.6.1 Permitted Activities
The following activities are permitted around distribution substations and
service pillars:
• planting of screening shrubs with limited spread and root system and not
requiring excavation below 200 mm.
6.6.2 Controlled Activities
The following may only be undertaken with Power and Water approval and then
only under such controlled conditions as Power and Water may specify:
• erection of fencing on the boundary of the easement provided all exposed
metal parts are earthed correctly and access to Power and Water
equipment is maintained (such as by the fitting of gates or removable
panels).
6.6.3 Prohibited Activities
The following activities are prohibited in underground cable easements except
under the most extreme circumstances. All other activities not specified as
“permitted” or “controlled” shall, unless and until ruled otherwise by Power and
Water in writing, be prohibited.
• any construction within the easement, including above ground swimming
pools
• any storage on the easement
• any increase in ground level above that existing at the substation or pillar
base and within 3 m of the easement boundary
• any excavation greater than 200 mm deep within 3 m of the easement
boundary
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• any excavation that would endanger the foundations of the substation or
pillar
• any earthworks that might direct stormwater onto the easement or cause
pooling of water in the vicinity of a substation, ring main unit or pillar
• any changes to construction within 8 m of a substation that could cause the
fire design of the installation to be compromised
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3 NT Land Titles Act Division 4
Appendix A
Part 1 – General Information on Electricity Easements
1.1 The Purpose of an Easement
Wherever Power and Water assets such as overhead power lines or underground
cables cross private land it is necessary for Power and Water to have an assured right
of access to construct, inspect and maintain the asset. Easements are established to
safeguard these needs. Rules for the use of an easement by others are set up to
ensure the safety of persons within the easement and to protect Power and Water’s
plant.
This in turn ensures that the security and reliability of service to customers can be
maintained, and requires that Power and Water can restrict activities within the
easement to minimise the risk of personal injury and to retain unimpeded access.
Throughout this document references to overhead lines and cables include all
associated equipment such as substations, switch yards and distribution pillars.
1.2 Definition of an Easement
An easement is an encumbrance on private land that gives Power and Water the right
to use and have access to the land for the purpose for which the easement is granted.
It is the subject of an Agreement which includes a description on the Title Plan showing
the dimensions of the easement.
1.3 How an Easement is Established
The need for an electricity easement arises when Power and Water is required to install
equipment to supply new customers or reinforce supply to existing customers, and
cannot reasonably do so using public land.
Most easements are established by developers when constructing subdivisions,
together with the power, water and sewerage assets required for the subdivision.
If the line or cable is required to cross land to supply the owner or occupier of the land,
then the granting of an easement is a condition of the supply of electricity and all costs
are borne by the applicant.
If the line or cable is to be installed to supply customers other than the land owner or
occupier then the owner may decline to grant an easement. In that event Power and
Water will make further attempts to find an alternative route. If no satisfactory
alternative route is found then Power and Water may invoke its powers of compulsory
acquisition to acquire the route across the private land. This is not preferred and is a
last resort.
An easement granted to or acquired by Power and Water is an easement in gross
within the meaning of the Land Titles Act.3