guide for near high voltage transmission lines

GUIDEFORDEVELOPMENT NEARHIGHVOLTAGE TRANSMISSIONLINES

INTRODUCTION

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HOWTOUSETHISGUIDE TRANSPOWERSCORRIDOR MANAGEMENTPOLICY DEVELOPMENTDESIGN RESIDENTIALDEVELOPMENT RURALRESIDENTIALDEVELOPMENT RETAILANDCOMMERCIAL DEVELOPMENT INDUSTRIALDEVELOPMENT OPENSPACEANDRECREATIONUSE RURALANDFORESTRY STRUCTUREPLANS PLANTINGNEAR TRANSMISSIONLINES DEVELOPMENTCHECKLIST SUMMARY BACKGROUNDWHOWEARE GLOSSARY ADDITIONALINFORMATION

Transpower is responsible for delivering and maintaining the supply of electricity throughout New Zealand. Electricity is delivered to towns and cities by means of high voltage overhead transmission lines that frequently cross private property. This guide provides information on how land with existing transmission lines can be developed in ways that are compatible with the presence of the lines.Transmission lines use air to insulate the conductors or wires. For this reason, the airspace around the conductors and towers must be kept clear. Breaching the airspace is like getting too close to a fire: you can still get burned even though you havent touched the flame. Getting too close to conductors could result in serious injury or death. Although clear airspace is required around transmission lines, it is still possible to develop and use the land near the conductors and towers safely for a range of compatible activities. This guide illustrates some of these activities and approaches to development.

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RemembertheselinesformpartoftheNationalGrid.Thelinesarealwaysworking carryinghugeamountsofelectricityathighvoltagestoensuretheareasofhighdemandget theelectricitytheyneed.Tostayoperatingwell,thelinesneedtobemaintained.Theyalso mayneedtobeupgradedatsometimeinthefuture.Yourdevelopmentshouldnothinder theongoingoperationofthelines.

This guide has been developed to show how land can be used in a way that protects the existing transmission lines, meets mandatory regulations and provides landowners with opportunities for reasonable use of their land. You are encouraged to discuss proposals with Transpower as early as possible to ensure the best outcomes.Whoisthisguidefor? This guide looks at a range of potential uses for land already carrying transmission lines, and it discusses ways to use the land around and beneath high voltage transmission lines safely and appropriately. It should be noted that some local distribution companies also have high voltage assets that are similar to Transpowers. Whilst the issues and risks discussed in this guide are likely to be similar for distribution lines, the guide relates only to Transpowers lines. Transmission lines owned by Transpower can be identified by signs located on each tower or pole. The guide is provided for: Landowners Developers Surveyors Landscape architects Local and regional authorities

HowtocontactTranspower Transpower New Zealand Ltd PO Box 1021, Wellington 6140 Tel: 0508 526 369 Email: [email protected]

Transpower has legal rights to access and maintain its lines. It is Transpowers preference, international best practice and required by the National Policy Statement on Electricity Transmission under the Resource Management Act to keep the area under lines free of buildings and structures. While Transpower doesnt always own the land on which lines are situated, it does have easements over part of the network. In fact, where Transpower has easements over the lines, it is usually a condition that no buildings, structures or planting of vegetation occurs within the easement area. In the absence of an easement, Transpower still recommends keeping the area clear and ensuring any nearby buildings or structures are adequately earthed or bonded. By setting back development from the lines, Transpowers rights to access the lines are provided for, safety risks are minimised and amenity outcomes are promoted. Transpowercanprovideexampleswheredevelopmenthassuccessfullyaccommodatedtherequirements oftheNationalGridandwheretheimpactsofthenetworkonthatdevelopmentaremanaged.

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HOWTOUSE THISGUIDEElectricitytransmissionlinecomponents This diagram illustrates terms used throughout the guide.

The guide is organised into sections that address different types of land development, such as residential and industrial development. You can refer to the section relevant to your proposal or work your way through the whole guide. The sections on structure plans and the development checklist cover broad planning concerns particularly relevant to local authorities, as well as anyone with a development proposal.The guide is not a complete reference source but is designed to alert you to some of the principal issues relating to development near transmission lines. You are advised to contact Transpower or a specialist engineer for information on safe and compliant development. Additional resources for finding further information are provided in the final section.

VIBRATION DAMPER

Whatmustyoucomplywith? The most important regulations that affect development around and under transmission lines are: New Zealand Electrical Code of Practice for Electrical Safe Distances (NZECP34:2001), referred to as NZECP34 available from http://www.ess.govt.nz/rules/pdf/nzecp34_2001.pdf Electrical (Hazards from Trees) Regulations 2003, referred to as Tree Regulations available from http://www.legislation.govt.nz Electricity Act 1992 and Electricity Regulations 1997 available from http://www.legislation.govt.nz district and regional plan requirements and the Resource Management Act 1991 check with your local council any registered easements over the land. These documents contain information on mandatory requirements relating to vegetation and development near existing assets. Transpowers Corridor Management Policy, which seeks that the area under lines is kept clear, is outlined on page 4. This guide provides general information only. For details relating to your specific plans, you will need to consult these regulations and get advice from a specialist engineer on safe and compliant development. Note:ThisguidedoesnotreplacetherequirementsoftheResourceManagement ActorBuildingAct2004youwillneedtodiscussyourdevelopmentplanswith yourlocalcouncil.

Keyissues Development can have unwanted and unintended effects on transmission lines. Likewise, the lines can adversely affect development. This guide highlights three key issues to keep in mind when developing land under and around transmission lines and towers: 1. Settingdevelopmentbackfrom existingtransmissionlines: Control safety risks to the public by establishing a buffer corridor between lines and development and by meeting the separation distances required by NZECP34. 2. Providingfortheongoingoperation oflines: Provide for the continued operation of the lines by ensuring vehicle access is preserved for inspection and maintenance and by avoiding the adverse effects of development and other activities on lines. 3. Promotinggooddevelopmentoutcomes: Plan and design development early to achieve the best possible outcomes for land use under lines and around towers.

NZECP34 Safe separation distances are outlined in NewZealandElectricalCodeofPractice forElectricalSafeDistances2001 (NZECP34). The code sets out the minimum separation distances for excavation and construction work and the operation of mobile plant near conductors and their support structures (towers and poles). The primary purpose of these distances is to protect persons and property from harm caused by electrical hazards, such as flashovers. Compliance withNZECP34ismandatoryunder Regulation93oftheElectricity Regulations1997. TreeRegulations The Electricity (Hazards from Trees) Regulations 2003 are designed to protect the security of supply of electricity and the safety of the public from hazards from trees. Any trees growing in the vicinity of high voltage transmission lines must be managed to comply with these regulations.

LINESAGANDSWING:Asthetemperatureoftheconductorscarryingtheelectricity increases,thesagoftheconductoralsoincreases.Thetemperatureoftheconductorsis affectedbyclimaticconditions(lackofwind,sunandwarmerairtemperatures)andthe changingamountofelectricitybeingtransmittedthroughthem.(Themorecurrentgoing throughtheline,thehottertheconductorbecomes.)Linescanalsoswinghorizontallyin highwinds,sometimesupto4m,especiallyoverlargerspans(e.g.betweentowersor poles).Separationdistancesarecalculatedforthemaximumsagandswingconditions. ITISVITALTOMAINTAINSEPARATIONDISTANCESFROMTHELINESATALLTIMES. FLASHOVERDANGER:Aflashoverisamajorelectricaldischarge,usuallyintheformofan electricarcthatleapsorarcsfromtheconductoracrosstheinsulatorstringtothetower(or fromtheconductortoanotherobject),resultinginashortcircuit.Flashoversmaybecaused byalightningstrike,contaminationoftheinsulatororwhenapersonorobjectistooclose tothelines.Whilstflashoversarerare,THEYAREEXTREMELYDANGEROUS,whichiswhy itisvitaltoalwaysmaintainseparationdistancesfromthelines.

REMEMBER:Thesetransmissionlinesarecarryingelectricityatveryhighvoltages. Electricityatthesevoltagescanarcthroughtheairevenwithoutdirectcontactgetting tooclosetolinesorholdingsomethingclosetoalineisEXTREMELYDANGEROUS.

HowtocontactTranspower If you require further information, please contact us at: Transpower New Zealand Ltd PO Box 1021, Wellington 6140 Tel: 0508 526 369 Email: [email protected]

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TRANSPOWERSCORRIDOR MANAGEMENTPOLICY

DEVELOPMENT DESIGN

Transpowers Corridor Management Policy has been developed to provide the public with information on the safe and efficient development options around existing transmission lines. Transpower will be guided by this policy when responding to enquiries or when participating in resource consent application processes or other processes under the Resource Management Act. Corridor management around our transmission lines is essential for maintaining: a safe and secure supply of electricity to all New Zealanders the safety of those living, working or playing near our lines. Our Corridor Management Policy seeks to ensure that only compatible activities are undertaken near our transmission lines, using a graduated scale of protection green, orange and red zones.

The following sections look at issues that may arise where land already crossed by transmission lines is developed for different uses. The sections are organised into land use categories such as residential or commercial. Sketches are used to illustrate the issues. Remember these lines form part of the National Grid. The lines are always working carrying huge amounts of electricity at high voltages to ensure the areas of high demand get the electricity they need. To continue operating well, the lines need to be maintained. They also may need to be upgraded at some time in the future. Your development should not hinder the ongoing operation of the lines. There are six sections relating to typical land uses:

1TransmissioncorridoractivitymanagementTower or pole Red zone measured 12m either side of transmission lines + NZECP34 distances around structures and conductor swing Orange zone measured 20m either side of the red zone Green zone beyond the orange zone Note: NZECP34 and the Tree Regulations will still apply.

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For each land use, some of the typical issues are identified and examples are presented of ways to avoid problems. In each case, the following questions are raised: Whatimpactwillthedevelopmenthaveonthetransmissionlines?

Whatimpactwillthetransmissionlineshaveonthedevelopment?

Howcantheseeffectsbeavoidedormitigated?

Whataboutthelandunderthelines?32m 12m 20m

It is Transpowers policy to: protect the red zone from any development manage the orange zone from inappropriate development inform developers of any risks associated with development in the green zone.

Itisbestpracticenottobuildwithinthetransmissioncorridor.Bysettingdevelopment backfromthelines,Transpowersrightstoaccessthelinesareprovidedfor,safetyrisks areminimisedandamenityoutcomesarepromoted. Whendesigningadevelopmentonlandwhereaneasementisinplace,thedeveloper mustcontactTranspowerbeforeplanninganyactivities,treesorstructuresthatare restrictedbythetermsoftheeasement. Remember,ifindoubt,discussyourproposalswithTranspower.

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Line corridor allocated as reserve Siting of house lots takes into account separation distances

NZECP34 respected

3REMEMBER:Thesetransmission linesarecarryingelectricityatvery highvoltages.Electricityatthese voltagescanarcthroughtheair,even withoutdirectcontactgettingtoo closetolines(includingtowers)or holdingsomethingclosetoalineis EXTREMELYDANGEROUS.

Whatimpactwillresidentialdevelopmenthaveonthetransmissionlines? Development that is built too close to the lines, towers or conductors may create an electrical hazard risk to persons or property nearby and can put at risk the operational security and safety of the lines. Encroaching development is also contrary to international best practice. Therefore, it is Transpowers preference for the area under the lines to be clear. Residential development may have other effects on the transmission lines. Tree planting on individual properties may pose a risk if owners are not aware of the Tree Regulations. If earthworks are required, they may destabilise towers or reduce separation distances. (Earthworks must also meet necessary NZECP34 separation distances.) Dust from construction earthworks may also adversely affect the functioning of the lines. Transpower can advise on how to manage the risk of trees, earthworks or dust adversely affecting the lines and towers. Preserveaccesstolines Plan roads and access to houses and other structures such as fences so that they also preserve vehicle access to towers and poles. This access is required for inspection and maintenance of lines. Screendwellingsfromlines Use planting close to houses to screen views of the towers or poles. It is more effective to plant closer to houses than to poles and towers for screening purposes. Planting closer to houses also avoids potential problems with trees not meeting the Tree Regulations. Some suitable species are suggested on page 30.


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Whatimpactwillthetransmissionlineshaveonresidentialdevelopment? The existing transmission lines may have a visual effect, but by designing in the lines, these impacts can be significantly reduced. The presence of the lines means the use of the land under the lines will need to be carefully managed, through consideration early in planning to optimise development outcomes. The separation distances required from the towers or poles and beneath the conductors will influence the density and placement of houses. Houses and other structures should be sited away from the towers or poles and beneath conductors so that they generally provide a clear corridor and comply with NZECP34. Placement of roads should also be designed not to exclude vehicle access to the towers (or poles) for inspection and maintenance. Transpowers Corridor Management Policy can be used as a guide to maintaining clear corridors.

Trees positioned close to house to screen tower

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NZECP34 respected

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Transmission corridor kept clear

Building within corridor, NZECP34 compromised, Tree Regulations issues




It is possible to develop land near high voltage transmission lines for residential use, provided the necessary safety and operational considerations are taken into account, including maintaining access to the lines and towers and complying with required separation distances. If proposals are well considered from the outset and use good urban design principles, the impacts of the lines can be reduced and the effects of the development on the lines can be well managed. It is worthwhile discussing your proposals with Transpower.

Howcantheseeffectsbeavoidedormitigated?RURALRESIDENTIAL DEVELOPMENT

The impact of the line can be reduced by planning and laying out development to take the presence of the overhead lines and any towers into account from the outset. Ensureseparationdistances Plan house lots and building platforms so the area under the lines is clear, which also means NZECP34 requirements will be met. All conductive fencing must be kept further than 5m from a pole or tower and should run perpendicular to the conductors. Discuss your proposals with Transpower.Access to lines is maintained

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Remember attaching anything to towers or poles, especially fences and metal items, is extremely dangerous and is not permitted by Transpower.

2RETAILANDCOMMERCIAL DEVELOPMENT Building platform positioned so view is less visually intrusive

Building platform positioned so tower is viewed

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3Whataboutthelandunderthelines? When designing a subdivision layout, subject to local authority approval, the area under the transmission lines could be used as the open-space area for passive recreation, which could include walking and biking tracks or (shallow) wetland areas that could serve as stormwater management for a subdivision or, if carefully designed, golf course fairways, sports fields or tennis courts. Dwellings and other buildings should not be located under the line, but the land could be used for utility purposes including gardens, lawns, paved areas, car parking or driveways. Transpower can advise on the issues associated with the use of land under the lines it is important to ensure development is designed with safety and operation of the lines in mind.INDUSTRIAL DEVELOPMENT

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Buildingorientation Situate building platforms so that houses look out under lines and between towers or poles, rather than looking at the towers or poles themselves. The conductors are much less visually obvious than either towers or poles.

It is Transpowers preference and international best practice to keep the area under lines free of structures. In fact, where Transpower has easements over the lines, it is usually a condition that no buildings, structures or planting of vegetation occurs within the easement area. In the absence of an easement, Transpower still recommends keeping the area clear and ensuring any nearby buildings or structures are adequately earthed or bonded.


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If fences around towers are constructed, they must meet the separation distances in NZECP34. For example, all conductive fencing must be kept further than 5m from a pole or tower and should run perpendicular to the conductors.

Whatimpactwillruralresidentialdevelopmenthaveonthetransmissionlines? The major impacts that rural residential development could have on transmission lines include restricting vehicle access to the towers or poles for inspection and maintenance, establishing dwellings, buildings and other structures too close to lines, and risks from planting trees too close to the towers or lines. The issues raised in the previous section on residential development may also apply.

3REMEMBER:Thesetransmissionlines arecarryingelectricityatveryhigh voltages.Electricityatthesevoltages canarcthroughtheair,evenwithout directcontactgettingtoocloseto lines(includingtowers)orholding somethingclosetoalineis EXTREMELYDANGEROUS.

Buildings positioned outside of line corridor Line corridor free from development NZECP34 respected

NZECP34 respected


Whatimpactwillthetransmissionlineshaveonruralresidentialdevelopment? To some extent, the transmission lines will dictate where dwellings, buildings or structures can be located. Development and activities (including earthworks) should not be carried out in the transmission corridor and, at all times, must meet mandatory separation distances from towers, poles and conductors (refer to NZECP34).

Trees used to screen lines from line of sight

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NZECP34 respected


Ensureaccesstolinesispreserved Any changes to land use should still allow for vehicle access to the existing towers or poles. This could be achieved by combining roads to individual houses with access to the base of towers, to keep roads and driveways to a minimum. Separation distances between line spans and roads are also covered in NZECP34.

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Rural residential or lifestyle block subdivision can be designed in a way that reduces the impacts of existing transmission lines. As this type of development is less dense than residential, it can provide sufficient space to ensure the new development does not adversely impact on the lines, such as by ensuring separation distances are met and maintaining vehicle access to lines and towers for inspection and maintenance. It is worthwhile discussing your proposals with Transpower.

Howcantheseeffectsbeavoidedormitigated?RURALRESIDENTIAL DEVELOPMENT

The necessary and appropriate separation distances between dwellings and other structures and the lines can be easily accommodated with good planning from the beginning. Early planning can also achieve appropriate access arrangements and tree planting. Discuss your proposals with Transpower. Establishbuildingsoutsideofthelinecorridor It is international best practice and Transpowers preference for all buildings to be established outside of the line corridor. In addition, the requirements of NZECP34 must be met. Seek advice from a qualified engineer on how to meet the requirements for separation distances from high voltage transmission lines for dwellings, buildings, earthworks and other structures.

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Visualimpact Careful orientation of individual houses and planting closer to the houses can screen views of the towers and poles and minimise their impact on views. Shelter belts or planting can be established near the transmission lines, providing separation distances and clearances required by the Tree Regulations are met.


NZECP34 respected

Trees used to screen tower placed adjacent to house rather than tower

Whatimpactwillretailandcommercialdevelopmenthaveonthetransmissionlines? Retail and commercial development can adversely affect the operation and maintenance of existing lines if it is built right up to and under the existing lines. This may be through obstructing access to the towers or poles and creating safety hazards by not maintaining mandatory separation distances. The construction phase may also adversely affect the lines, as earthworks could change the ground level, affecting separation distances, and dust from construction or day-to-day activities can also cause significant problems for the lines Transpower can advise on dust mitigation to avoid this. Use of mobile plant (e.g. cranes, forklifts, front-end loaders) could also pose a hazard to both the lines and the safety of the operators. Seek the advice of Transpower or a specialist engineer to advise on safe and compliant retail and commercial development.

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Line corridor kept clear


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Breach of Tree Regulations with trees placed too close to tower

Whatimpactwillthetransmissionlineshaveonretail andcommercialdevelopment? The transmission lines will place some restrictions on how the land can be developed, but careful planning to address these limitations can produce innovative and efficient development solutions. The need to set development back from the transmission lines will restrict heights of buildings and structures around the lines, but as distance from the lines increases, this restriction disappears. The visual impact of the towers or poles is often less of a concern in areas proposed for commercial or retail development, as the scale and design of that type of development may reduce the perceived size of the towers and poles. Remember these lines form part of the National Grid. The lines are always working carrying huge amounts of electricity at high voltages to ensure the areas of high demand get the electricity they need. To stay operating well, the lines need to be maintained. They also may need to be upgraded at some time in the future. Your development should not hinder the ongoing operation of the lines.REMEMBER:Thesetransmissionlines arecarryingelectricityatveryhigh voltages.Electricityatthesevoltages canarcthroughtheair,evenwithout directcontactgettingtoocloseto lines(includingtowers)orholding somethingclosetoalineis EXTREMELYDANGEROUS.


5REMEMBER:Youmustcomplywith theTreeRegulationsandNZECP34.

Whataboutthelandunderthelines? The land under the lines can be used efficiently if the development is carefully designed, maintaining a clear corridor. For rural residential development, these uses could include open space for stock grazing, stormwater swales or run-off detention areas (provided the waterway is not likely to undermine structure stability) or passive recreation such as walking, biking or horse-riding trails. Dwellings and other buildings should not be located under the lines. Remember, utility structures such as sheds, barns and other buildings must also comply with NZECP34 separation distances and any easements that are registered against the property. The matters discussed on page 30 in the section Planting near transmission lines and in the previous section on residential development will also apply.

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Retail and commercial development usually seeks to maximise the use of the available space. Good and early planning that takes account of the existing lines and required separation distances, access and other safety and operational requirements is therefore essential. It is worthwhile discussing your proposals with Transpower in the early stages of planning the development.

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1Howcantheseeffectsbeavoidedormitigated?RURALRESIDENTIAL DEVELOPMENT

If in doubt, discuss your proposal with Transpower or seek a qualified engineers advice.


Ensureseparationdistances Ensure buildings are set back away from lines and meet NZECP34 requirements for electrical safety. The scale and design of buildings can also reduce the visual impact of the lines.Using lower building height nearer to the lines and increasing height with distance from the line can reduce visual impact

Whataboutthelandunderthelines? Buildings and other structures should not be located under the lines. The area can be used, for example, for car parking or internal roads providing that the necessary separation distances are maintained and NZECP34 is complied with. For retail developments, this may be a suitable place for car parking or for internal roads.

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Preserveaccesstolines Locating activities such as car parking or access roads under the lines to keep the transmission corridors clear will meet the separation distances required by NZECP34, and vehicle access to towers and poles will be maintained so inspections and maintenance can be carried out as normal.


5Ancillary activities such as car parking are suitable closer to towers

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The area under the lines could be used for low-level display and storage of (non-flammable and non-explosive) goods and wares, but particular care must be taken with the use of mobile plant (e.g. cranes or forklifts). Remember NZECP34 also relates to mandatory separation distances for mobile plant.




Plan the site layout to ensure the buildings and structures are not located within the transmission corridor and that the separation distances required by NZECP34 are met. Use lower building heights nearer to the lines and increase building height as distance away from the lines increases. Other urban design principles may also apply. Discuss your proposals with Transpower.

Ensuresafety Long sections of metal roofing or walls parallel to the transmission lines can act as a circuit these should be broken up by inserting sections made of non-conductive materials e.g. timber. Ensure metal buildings and structures, including building cladding, are earthed or bonded. A specialist engineer can advise on safe and compliant development. NZECP34 also sets out separation distances for fences around poles or towers.


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REMEMBER:Thesetransmissionlines arecarryingelectricityatveryhigh voltages.Electricityatthesevoltages canarcthroughtheair,evenwithout directcontactgettingtoocloseto lines(includingtowers)orholding somethingclosetoalineis EXTREMELYDANGEROUS.


Whatimpactwillindustrialdevelopmenthaveonthetransmissionlines? As with commercial development, industrial buildings or structures can have significant adverse effects on existing transmission lines. Building too close to towers and conductors and not meeting the required separation distances can create unsafe situations and may result in a line being completely built out, restricting access for line upgrading and maintenance works. Impacts can also arise from the type of industry proposed. Industries that involve particulate or hot gas emissions (e.g. cement plants and quarries), major earthworks and particularly corrosive emissions can create major impacts, including reducing insulator performance and increasing the risk of flashovers. Industry that requires large heavy machinery or mobile plant may also create dangerous situations if it breaches NZECP34 separation distances. Remember these lines form part of the National Grid. The lines are always working carrying huge amounts of electricity at high voltages to ensure the areas of high demand get the electricity they need. To stay operating well, the lines need to be maintained. They also may need to be upgraded at some time in the future. Your development should not hinder the ongoing operation of the lines.

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Ensureseparationdistances Make sure buildings and structures are well separated from the transmission lines, including complying with the set-backs required by NZECP34. Refer to Transpowers Corridor Management Policy for guidance. Do not attach anything to a tower or pole, and make sure access for maintenance is preserved. If fences around towers are constructed, they must meet the separation distances in NZECP34.



Whatimpactwillthetransmissionlineshaveonindustrialdevelopment? The transmission lines will place some restrictions on how the land can be developed, but careful planning to address these limitations can produce innovative and efficient development solutions. The separation distances required around the towers or poles and beneath the conductors will influence the placement of buildings and structures, their heights and the kinds of industry that can take place. Visual issues are less important as the character of industrial areas is generally suited to the presence of the lines.

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Industrial development, like retail and commercial, tends to maximise the use of the available space. Therefore, good planning is essential when determining site design and layout, in order to take account of the operational needs of the lines, required separation distances and safety and access issues. It is worthwhile discussing your development proposals in the early stages with Transpower.

Howcantheseeffectsbeavoidedormitigated? Develop land under and around transmission lines for industries that are compatible with the operation of the transmission lines. Make sure the risks associated with proximity to the transmission lines are known and understood and that measures are taken to ensure safety. Discuss your proposals with Transpower.

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1Whataboutthelandunderthelines? Land under the lines can be used, depending on the activity and ensuring Transpower can still access its lines. However, buildings and structures should not be located under or too close to the lines. The area under the lines can be used for car parking or for internal roads. Refer to Transpowers Corridor Management Policy for guidance. If stockpiling soil or similar materials, make sure that any change to the ground level beneath the transmission lines does not encroach into the separation distances required by NZECP34. Similarly, avoid excavating adjacent to towers or poles as this may undermine the stability of the towers or poles. Dust generated in construction or day-to-day activities may also adversely affect the lines. If excavation is necessary near towers or poles, consult NZECP34 and get the advice of a specialist engineer to ensure separation distances are maintained. All other structures must also meet the NZECP34 separation distances. It would be worthwhile discussing proposals with Transpower.RURALRESIDENTIAL DEVELOPMENT

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Therearesomeopenspaceactivitiesthatmustbeavoidedneartransmissionlines:

Kiteflying: The kite string can create a dangerous electrical hazard risk if any part of the kite touches the conductors.INDUSTRIAL DEVELOPMENT

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Boating: Be aware of the height of masts when passing underneath transmission lines.


Lightaircraftandhelicopters: Avoid flying near or around transmission lines, and site airstrips or landing pads away from transmission lines.

5Fishing: Casting can result in the fishing line coming into contact with the conductors and becoming a conductor itself.

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Other recreation activities, including sports grounds, golf courses, walkways and cycleways, may be located near transmission lines, provided they are well designed to ensure public safety, any trees comply with the Tree Regulations and buildings and structures meet the Corridor Management Policy and NZECP34 separation distances. You are encouraged to discuss proposals with Transpower in the early stages of planning the development.

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Land under and around transmission line conductors can be used as open space and for recreation. Many activities are compatible with the presence of the lines, provided that the necessary separation distances are maintained (to meet Transpowers Corridor Management Policy and NZECP34), tree planting complies with the Tree Regulations and general safety measures are observed such as those described in Transpowers Working on Your Land Booklet. It is worthwhile discussing proposals with Transpower in the early stages of planning the development.


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1Whatimpactwillthetransmissionlineshaveonopenspace andrecreationdevelopment?RURALRESIDENTIAL DEVELOPMENT

Many recreation activities can safely take place under and around transmission lines, but the transmission lines will place some restrictions on how the land can be developed and used. Refer to Transpowers Corridor Management Policy for guidance. Creating good quality designs through careful planning to address these limitations can produce innovative and efficient development solutions. The lines may determine the location of tall structures, such as floodlights, so they meet separation distances. Landscape and visual effects may also arise from the visual dominance of the line when viewed along its length. Since the transmission line forms a corridor, this is more obvious when the recreation use, such as a bike or walking track, runs directly parallel to or along the same linear corridor.


Howcantheseeffectsbeavoidedormitigated? Designofopenspace Much of the visual impact from looking along a line of towers can be mitigated by carefully designing paths and tracks so they cross backwards and forwards under the lines rather than running parallel to them. Careful planting of shrubs and low trees can also screen longer views. Discuss your proposals with Transpower. Wetlandsandconservation Nature conservation and wildlife habitat is also suitable provided that tree planting is kept away from the towers or poles and lines themselves. All vegetation must meet the heights stipulated in the Tree Regulations to avoid creating electrical hazard situations. Planting tall-growing trees that do not breach the Tree Regulations but may cause a hazard if they fall over onto a transmission line or tower should also be avoided. Refer to Transpowers Corridor Management Policy for guidance. Transmission corridors can also provide a good opportunity to create wetland areas or wildlife corridors through built-up areas, provided that vehicle access to the towers or poles is maintained. Wetlands can be successfully developed, although care must be taken not to undermine foundations. Transpower can advise on ways to avoid other operational problems that may arise from wetlands.

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Ensureseparationdistances Recreation uses that require large areas, such as sports fields, golf courses or courts, could be appropriate near the spans of conductors. Ensure any structural elements, such as rugby goal posts, stands or lighting, comply with the separation distances. Refer to Transpowers Corridor Management Policy and consult a qualified engineer and NZECP34 to determine separation distances from towers and poles.


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RURALAND FORESTRYRESIDENTIAL DEVELOPMENT RESIDENTIAL DEVELOPMENT





Whatimpactwillruralandforestrydevelopmenthaveonthetransmissionlines? Most impacts will come from buildings and structures failing to meet the required separation distances, from shelterbelts and plantations that are established too close to conductors and towers and that do not meet the Tree Regulations clearances, and from related activities that may create a hazard, e.g. irrigation, burning off and spreading fertiliser.

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Whatimpactwillthetransmissionlineshaveonruralandforestrydevelopment? In general, existing transmission lines do not place major restrictions on rural land uses. Most farming activities are compatible with the presence of the lines, although some changes to farm operational and management activities may be required. Lines may also impact the subsequent development of rural land, for example, if the land was to be rezoned for residential use. If land is being proposed for conversion to forestry or horticultural uses such as grapes or orchards, the presence of the transmission lines will impose some constraints on the way the land is developed. You will need to ensure new structures such as fences are constructed in sections and earthed or bonded appropriately and ensure separation distances and access to lines is maintained. However, the lines themselves do not preclude this use. If in doubt, discuss your plans with Transpower. Separationdistances Locate farm sheds, hay barns and other buildings and structures away from towers, poles and conductors, as outlined in Transpowers Corridor Management Policy. This will ensure vehicle access is available to the towers or poles and lines and ensure compliance with NZECP34 distances.

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RURALAND FORESTRY

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RURALAND FORESTRY




Rural and forestry land uses can generally happily coexist with transmission lines, provided that the Tree Regulations 2003 are complied with and any structures, buildings or mobile plant (such as cranes, diggers and so on) comply with necessary separation distances. However, some activities, such as irrigating, burning off or spreading fertiliser, will need to be managed to ensure the existing lines arent adversely affected. It is worthwhile discussing your proposals with Transpower.

Howcantheseeffectsbeavoidedormitigated? TreeRegulations Ensure that forestry plantings and shelterbelts maintain the separation distances required by the Tree Regulations and provide for vehicle access to lines for inspection and maintenance. Use the mature height of the trees to determine the required separation distances. Low-growing species may be suitable, even under the conductors, if the vertical clearances and access required are ensured. However, be aware that tall-growing trees that dont breach the Tree Regulations could still cause a hazard if they fall on a line or tower. Discuss your proposals with Transpower.

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The line may also pose a hazard to helicopters and planes that are topdressing or spraying. Make sure the lines exact location is marked on the flight map and, if possible, avoid spraying or topdressing in patterns that require the flight path to cross the line. Fly parallel to the line whenever possible. It is safest to cross a line at a tower, rather than mid-span.

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!OPENSPACEAND RECREATIONUSE OPENSPACEAND RECREATIONUSE

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RURALAND FORESTRY

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RURALAND FORESTRY


Keep irrigators and other spray units well away from towers, poles and conductors. Adjust nozzles to make sure they are not spraying onto the conductors, jets are turned off when the boom passes by the towers and the boom stays well clear of the conductors.



Avoidelectricalhazards Long runs of metal and wire fencing parallel to the transmission lines need to be broken up with either non-conductive sections or by inserting insulators. Without this, hazardous voltages can be transferred along the fence or other structure. NZECP34 sets out separation distances for fencing from towers or poles. For example, all fencing must also be kept more than 5m from a pole or tower and, where possible, the fencing should run perpendicular to the direction of the conductors.

Whataboutthelandunderthelines? There are some precautions that need to be taken when carrying out normal farming and forestry activities under the lines. As illustrated, care must be taken with planting, fencing and establishing other structures near the line. Consult a qualified engineer to ensure structures are earthed or bonded appropriately.


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STRUCTUREPLANS

WHENINDOUBT Discussyourproposals withTranspower.

Transmission lines often pass across farmland near urban areas. Over time, this land may be required for urban expansion or may become attractive to developers, and its use may change, for example, for rural residential lifestyle blocks, for residential development, for retail or commercial development or for recreation use. This change of land use can be compatible with existing transmission lines if development is well designed to address the lines safety and operational requirements.Structure plans may be developed by councils or developers as a way to plan the early stages of such development. Plans may identify site layout, access, open space, building platforms and land uses. This early planning provides an excellent opportunity to achieve a quality development that meets the necessary legal requirements and has good amenity and safety outcomes. Transpowers Corridor Management Policy is a good starting point. Therefore it is worthwhile to discuss your proposals with Transpower and seek specialist electrical engineering advice in the early stages of preparing structure plans. Principlestoguidestructureplans The following principles relate to preparing structure or concept plans for sites already traversed by transmission lines.

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SitelayoutanddesignPRINCIPLE: The transmission line corridor will influence the site layout. By understanding the requirements of the existing lines and designing in the lines, new development can meet the necessary separation distances, accommodate the safety and operational requirements of the lines and minimise amenity impacts.

There are different ways to achieve this:EXAMPLE1:

Use the land closest to the corridor for commercial activity and land further away for residential activity. Remember the land use closest to the lines should be oriented to provide sufficient set backs.KEYResidential Medium density commercial High density commercial Transmission line Roads

KEYResidential Medium density commercial High density commercial Transmission line Roads

EXPLANATION:

1 Sitelayoutanddesign,examples on page 27. 2 Landusesandactivities,examples on page 28. 3 Providingservicestodevelopments,examples on page 29.RemembertheselinesformpartoftheNationalGrid.Thelinesarealwaysworking carryinghugeamountsofelectricityathighvoltagestoensuretheareasofhigh demandgettheelectricitytheyneed.Tostayoperatingwell,thelinesneedtobe maintained.Theyalsomayneedtobeupgradedatsometimeinthefuture.Your developmentshouldnothindertheongoingoperationofthelines.

Commercial activities can use the area near the line for buildings, car parking or some ancillary activities, ensuring buildings are set back and NZECP34 is complied with. Refer to Transpowers Corridor Management Policy. Managing effects on residential development is easier when residential development is located further away from the lines. Use land under lines to create open space areas or accessways within the development.KEYResidential

EXAMPLE2:

KEYResidential

Open space Medium density commercial High density commercial Transmission line Roads

Open space Medium density commercial High density commercial Transmission line Roads

EXPLANATION:

By incorporating the transmission line corridor as open space within the development, the required separation distances and access requirements can be readily achieved. This also promotes a good outcome for the development, with residential use being set back away from lines.27

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PRINCIPLE:Grade

density of development so that it increases with distance from the transmission lines. Site low-lying buildings or activities closer to lines, with taller buildings further away.KEYLow height

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ProvidingservicestodevelopmentsPRINCIPLE: When planning the servicing of a new development, avoid establishing conductive infrastructure systems (power, telephone cables or gas lines) parallel to the alignment of the transmission lines (unless solutions are engineered to enable co-location). EXAMPLE5:Consider

EXAMPLE3:

KEYLow height

the safety aspects of infrastructure servicing early in the site layout and design phase. Seek engineering advice to ensure services are installed appropriately. If in doubt, discuss the proposal with Transpower.KEYTransmission lines Roads Railway Water Gas

Medium height

Medium height

High height Transmission line Roads

High height Transmission line Roads

KEYTransmission lines Roads Railway Water Gas

EXPLANATION:

Maintaining lower densities of development immediately adjacent to the transmission lines ensures that separation distances can be maintained and that access to towers remains available.EXPLANATION:

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LandusesandactivitiesPRINCIPLE: Consider using the separation distances under the conductors for land uses that dont require buildings or structures, for example, car parking. EXAMPLE4:

Land could be used to accommodate activities like car parking that are compatible with overhead lines.KEYBuildings

High voltages can be transferred when infrastructure systems such as telecommunications, conductive water supply pipes and railway lines are aligned parallel to high voltage transmission lines. Because these other systems typically follow road alignments, major roads should be aligned so they pass under the transmission lines at an angle. Using non-conductive materials can also avoid this problem. If in doubt, discuss your proposal with Transpower or seek a qualified engineers advice.

KEYBuildings

Transmission lines Roads Separation distances

Transmission lines Roads Separation distances

EXPLANATION: Clearance from towers or poles and conductors means there may be some areas available that cant be built on but could be used for other purposes. Development land is always at a premium, but with early planning, efficient uses for the land can be identified.

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PLANTINGNEAR TRANSMISSIONLINES

DEVELOPMENT CHECKLIST

Tree planting under high voltage lines may become a problem if the trees grow tall enough to interfere with the lines or fall on the conductors. The Tree Regulations prescribe the safe clearance guidelines for trees. Trees must also remain sufficiently far from the conductors that, if a tree falls in a storm, it will not make contact with the conductors.REMEMBER:Thesetransmissionlines arecarryingelectricityatveryhigh voltages.Electricityatthesevoltages canarcthroughtheair,evenwithout directcontact.Treesplantedtooclose tohighvoltagelinesareEXTREMELY DANGEROUS,canbeafireriskand cancausemajorelectricityinterruptions. Donotplanttreesinareaswherethey couldeventuallytouchorfallacross highvoltagelines.Youmustcomply withtheTreeRegulations2003.

When considering the development of land with high voltage transmission lines or when considering a resource consent application, there are some things that should be included:General Discuss your plans with Transpower and, in particular, check Transpowers Corridor Management Policy. Check the relevant district and regional plan rules and maps there may be specific provisions relating to development near lines and requiring separation distances from lines. Ensure that you are aware of the land use constraints imposed by existing high voltage transmission lines, in order to appropriately and accurately manage land use and reverse sensitivity issues. Where your proposed development or activity may adversely impact on or be impacted by existing high voltage transmission lines, you should discuss plans with Transpower, particularly when considering mitigation measures or appropriate conditions to place on consents. Site visit check for transmission lines on site. Changeofuse Discuss your plans with Transpower or seek specialist electrical engineering advice. Check plans to make sure buildings, structures, dwellings and fencing are set back from the lines as outlined in Transpowers Corridor Management Policy and also meet the mandatory minimum separation distances from towers or poles and conductors required by NZECP34. Check whether structures will be established parallel to existing lines. These can conduct electricity and so will need to be insulated or bonded seek specialist engineering advice. Vehicle access to existing structures must be preserved. Nothing should be attached to poles, towers or lines. Ensure no flammable, explosive or dangerous goods are stored or held beneath transmission lines.

In practical terms, a good way to avoid any problems with tree planting is to develop a graduated zone of planting for areas under and around transmission lines. Immediately under the conductors, the planting must be kept low, by using species that do not grow tall. This is a cheaper and easier solution than relying on trimming and maintenance. Instead of planting large trees such as oaks, elms, pines, poplars and eucalypts, consider planting smaller, more compact species. Suitable species include:

REMEMBER:Lookup!Iftherearelines overyoursite,Transpowermaybean affectedpartyandshouldbeconsulted.

Japanese Maple Birch Dodonea

Acacia Kowhai Prunus and Malus species (flowering cherry and apple)

Robinia Pittosporum

Small orchard species can generally be grown without risk under transmission lines. Hedges and shrub planting pose few problems, and ground covers are obviously suitable. However, you should discuss with Transpower the potential impact on the lines of spraying. As the distance from the lines increases, the height of the planting can be gradually increased until tall trees can be safely planted. A useful rule of thumb is that a tree should be planted no closer to the transmission lines than 1.5 times the mature height of the tree.REMEMBER:Youmustcomply withtheTreeRegulations.

Graduate plant heights so lower plants are closest to the conductors

Mature tree height

smaller

Mobile plant and machinery (e.g. forklifts, cranes) must meet mandatory separation distances at all times (NZECP34). Earthworks

larger Distance from line = mature tree height x 1.5

Ensure developers know their obligations discuss your plans with Transpower or seek specialist engineering advice. Ensure earthworks will not generate particulates or emissions that will adversely affect the existing transmission lines.

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SUMMARY

Ensure earthworks resulting in raising or lowering ground levels comply with the mandatory separation distances requirements of NZECP34. Ensure earthworks do not undermine or affect the stability of existing structures such as transmission towers this can be ensured by complying with required separation distances set out in NZECP34. Subdivision Discuss your plans with Transpower consider the implications of the Corridor Management Policy. Ensure that new lots can accommodate dwellings/buildings that meet the necessary separation distances from transmission lines, including towers, poles and conductors. Ensure that vehicle access to the existing structures is preserved. Existingeasementsovertheland Check whether the proposed use of the land will conflict with any easements registered against the land or any overriding statutory rights that Transpower may have. If in doubt about the effect of any proposed use, contact Transpower to discuss the proposal. Planting/landscaping Discuss your plans with Transpower or seek specialist electrical engineering advice. Ensure the trees or plants you are planting are not going to breach maximum tree heights and minimum distances from the line as set out in the Electricity (Hazards from Trees) Regulations 2003. Remember Transpower has rights to trim trees that may pose a hazard to existing lines. Ensure trees and fences do not restrict existing access arrangements e.g. for maintenance of towers or lines. Discharges Air discharges, such as abrasive blasting, dust from gravel extraction, application of fertiliser, corrosive particles or water particulates from irrigation, can have significant adverse effects on existing lines but can usually be managed or mitigated so that these effects are reduced to an acceptable level. Discuss the proposal with Transpower or seek specialist engineering advice. Wateruseortake Check whether changes to water bodies will affect the stability of lines or support structures (towers or poles). Discuss the proposal with Transpower if it is likely the use of water will contact the lines or structures. Mobile plant and machinery (e.g. spray irrigators) must meet mandatory separation distances at all times (NZECP34).

Summaryof ways to mitigate impacts of development on the lines and impacts of the lines on development:Ensuringsafety Establish and maintain separation distances between conductors, towers or poles and all structures, buildings, dwellings and conductive fences to ensure compliance with NZECP34. The Corridor Management Policy is a good reference point. Ensure that any changes in ground level under or around the towers or poles do not change the separation distances to the conductors. Ensure building services like power and telephone cables and gas lines are installed so they do not create electrical hazards. Ensure that the distances between any tree, fence, structure or object that could fall over (including lighting standards, sports field goal posts, flagpoles and trees) meet mandatory separation distances (use NZECP34 and the Tree Regulations to check distances). Never attach anything to a conductor, tower or pole. Make sure metal structures are appropriately earthed seek qualified engineering advice. Discuss plans with Transpower or seek qualified engineering advice. Ensure long runs of metal and wire fencing parallel to transmission lines are broken up with non-conductive sections or by inserting insulators. Providingforaccessandoperationofthelines Maintain vehicle access to the towers or poles and lines avoid building out or fencing off access to existing towers or poles. Put methods in place to mitigate the effects of the activities that generate dust or other particulates that contribute to build-up on the conductors. Check that earthworks do not undermine stability of structures. Comply with NZECP34 and the Tree Regulations. Achievinggooddevelopmentoutcomes Plan early to design in the transmission lines. Orient dwellings so they face across the corridor (rather than along it). Arrange building platforms so houses have views of conductors rather than of towers or poles. Plant near the dwelling to screen towers and poles, not near the structures themselves. Use the area required for separation distances for open space and passive recreation development. Design open space, walkways or cycleways to meander under the lines rather than following the same straight alignment as the lines. Ensure planting does not encroach into separation distances. (Refer to the section on planting for suggested species to plant near lines.)

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BACKGROUND WHOWEARE

Linesandlanduses:summaryofincompatibleactivities Some activities are simply not appropriate to locate under transmission lines because of safety risks or effects on the operation of the lines. Examples include: activities that emit dust, hot gases or corrosive particles (e.g. coal-fired boilers, sandblasting, cement plant) irrigation, where spray may reach conductors fires (including burning of stubble) activities that require the use of machinery that operates by raising or lowering (e.g. cranes, forklifts) any structures, buildings or earthworks located closer to the lines than the regulations allow placement of excavated fill, refuse or fallen timber any activities, including congregation of people, occurring directly under towers petrol or diesel storage or dispensing flying kites or model aircraft swimming pools tall-growing vegetation. Otheractivities Other activities may be compatible with existing transmission lines provided they are designed to avoid electrical hazards or risks posed by the lines and to accommodate the safety and operational requirements of the lines. To ensure the development complies with necessary regulations and avoids electrical hazards, it is advised to discuss the proposal with Transpower or obtain qualified electrical engineering advice. Transpowercanprovideexampleswheredevelopmenthassuccessfullyaccommodated therequirementsoftheNationalGridandwheretheimpactsofthenetworkonthat developmentaremanaged.

Transpowers network of transmission lines (the National Grid) transports electricity at high voltages from electricity generators to lines companies (for distribution to consumers via local networks) and directly to major industrial users.The core network comprises mostly 220kV and 110kV alternating current (AC) lines, as well as a 350kV direct current (DC) line from Benmore in the South Island to Haywards in the lower North Island, crossing under Cook Strait via the Cook Strait cables. The configuration of the various lines enables individual lines to operate as a network, where electricity can be sent in different directions depending on where the demand is. Because the network is a dynamic system, it is continually requiring maintenance and upgrading and sometimes extension in order to meet New Zealands growing demand for electricity. Transpowers lines were generally established under statutory provisions, including the various Public Works Acts since 1908 and the Electricity Act 1968 and subsequent amendments. Transpower has statutory rights to the continued ownership and operation of transmission lines built before 1 January 1988, which includes rights to carry out works necessary to inspect, operate and maintain lines. However, as these rights were provided for in statutes, they do not generally appear on certificates of title for affected land. Since 1988 (when new provisions of the relevant legislation came into effect), Transpower has negotiated easements for any new lines the easement is registered on the certificate of title for the land, and the terms of the easement bind any subsequent owners. Transpower has produced a Landowners Booklet, which contains important information for landowners and occupiers who have Transpowers assets on or crossing their properties. It details the rights and obligations of landowners and occupiers, safety and health issues and provides contact information for general enquiries and in case of an emergency. For further information, please contact: Transpower New Zealand Ltd PO Box 1021, Wellington 6140 Tel: 0508 526 369 Email: [email protected]

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GLOSSARY

ADDITIONAL INFORMATION

ARCING Electrical discharging, usually along the outside surfaces of an insulator, which occurs as the electricity leaks to earth. Minor arcing is heard as buzzing or frying sounds and may be visible at night as small intermittent flashes. A major arc is a flashover. CONCEPTPLAN CONDUCTORS

Electricity Act 1992. Available from http://www.legislation.govt.nz. Electricity Engineers Association Guide to Risk Based Earthing System Design, 2003. See http://www.eea.co.nz/EEA%20Publications.pdf. (Tree Regulations) Electrical (Hazards from Trees) Regulations 2003. Available from http://www.legislation.govt.nz. International Commission on Non-Ionizing Radiation Protection. See http://www.icnirp.de. New Zealand Committee for the Co-ordination of Power and Telecommunication Systems (NZCCPTS) guidance. Various guides available from http://www.eea.co.nz. New Zealand Electrical Code of Practice for Electrical Safe Distances (NZECP34:2001). See http://www.ess.govt.nz/rules/pdf/nzecp34_2001.pdf. New Zealand National Radiation Laboratory, Ministry of Health. Your health and fields from electric lines. See http://www.nrl.moh.govt.nz/EMF.pdf. Transpower. Factsheets 15 on Electric and Magnetic Fields and your health. Available by free download from http://www.transpower.co.nz. Transpower. Landowners Booklet. Available by free download from http://www.transpower.co.nz. World Health Organization EMF information. See http://www.who.int/peh-emf/en/.

See structure plan.

The conductors are the wires that carry electricity along the transmission lines and are made of copper or steel-reinforced aluminium.

NZECP34

New Zealand Electrical Code of Practice for Electrical Safe Distances 2001 (NZECP34:2001). NZECP34:2001 sets out the minimum safe distances for excavation and construction of structures or buildings and the operation of mobile plant near conductors and their support structures. The primary purpose of these distances is to protect persons and property from harm caused by electrical hazards, such as flashovers. (Available from http://www.ess.govt.nz/rules/pdf/nzecp34_2001.pdf.)

FLASHOVER

A momentary, but major, electric arc, usually across an insulator string. Each flashover is accompanied by a brilliant flash and a loud bang and results in a short circuit. Flashovers can also occur between two conductors or between a conductor and an object underneath the line, such as a tree or a crane jib. A fire under the line may cause a flashover from a conductor direct to ground. With transmission lines, objects do not need to actually touch the conductors to cause a flashover, as the arc can jump (over a metre in some circumstances). In general, flashovers are rare and may indicate a problem with the line. Always report flashovers.

POLESANDTOWERS

Support structures that have crossarms to hold the conductors clear of the ground. These structures and their foundations are designed to be strong enough to safely carry the weight of the conductors and withstand storm forces or wind. The mandatory distance a structure, earthworks or mobile plant (e.g. crane, forklift) is permitted from existing transmission lines (conductors and towers or poles). Refer NZECP34.

SEPARATIONDISTANCEORSET-BACK

STRUCTUREPLAN A broadly focused planning framework to guide the development or redevelopment of a particular area by defining the future development and land use patterns, areas of open space, the layout and nature of infrastructure (including transportation links) and other key features for managing the effects of development. Structure plans comprise maps, illustrations or diagrams of the proposed layout, features and links for areas being developed or redeveloped. TREEREGULATIONS

The purpose of the Electricity (Hazards from Trees) Regulations 2003 is to protect the security of supply of electricity, and the safety of the public, from hazards from trees. The schedule to the Tree Regulations identifies the growth limit zones in relation to trees growing near transmission lines. Any trees planted in the vicinity of high voltage transmission lines must be located and managed to comply with these regulations. (Available from http://www.legislation.govt.nz.)

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FEBRUARY 2010

guide for near high voltage transmission lines

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