Important Guidelines and Considerations
When preparing a request for authorization, there are technical considerations to keep in mind. A number of these are outlined below. This is not intended to be a comprehensive list of requirements but aims to serve as a guide for preparing a proposal. Reviews for each individual request are conducted by NB Power and may require months to complete, depending on the complexity of the proposal.
Transmission wires can sag lower to the ground depending on things like temperature and operating conditions. Minimum vertical clearances must be maintained from the maximum design sag levels of the conductors (worst-case scenario). NB Power will review these clearances as they are case-specific and not immediately apparent.
Access to Structures
A minimum 6-metre wide access path to NB Power facilities on the corridor must be provided for vehicles. A 15-metre clear working radius around transmission structures is required to maintain access for vehicles. A 3-metre radius around each tower footing must be left unpaved for access to the footing.
Grading, Drainage and Stormwater Management
- Grading changes must not impact vertical clearance requirements or result in standing water anywhere along the corridor.
- No fill material may be placed on the ROW without authorization from NB Power.
- Catch basins that are not positioned within a paved roadway are not permitted.
- Stormwater management ponds
- cannot exceed two-thirds of the corridor width under 69, 138 and 230 kV transmission lines,
- cannot exceed one-third of the corridor width under 345 kV transmission lines, and
- must be designed to withstand the effects of severe storm conditions.
Power Lines and Water
Water and electricity are a dangerous combination. Never allow water to spray on power lines. A hose or pipe spraying a power line can create a direct current through the watering equipment. Use low-angle irrigation equipment to maintain a safe clearance between the water jet and wires.
Before moving irrigation equipment, look up and around to note any nearby power lines —and stay clear. Working too close to electrical lines could be fatal or cause serious injury.
Roads and Parking
Roads crossing the ROW should be perpendicular to the corridor. Curb cuts or access gates should be provided for NB Power vehicles. Parking facilities on 69, 138 and 230 kV ROWs should be restricted to passenger vehicles only; parking for large trucks and trailers is not permitted. No parking areas are permitted under 345 kV ROWs. Transmission towers near roads and parking areas must be protected by standard highway barriers.
Pipelines and Underground Facilities
All underground facilities must be designed to withstand the loading conditions created by heavy maintenance vehicles that may be used by NB Power. The ROW must be restored to pre-construction condition once the project is completed. Excavation using heavy machinery is prohibited within 10 metres of tower footings to protect foundations. Within 10 metres, excavation must be carried out by hand or by use of a vacuum excavation system. Pipelines on ROWs must adhere to the provisions of CSA Standard C22.3 No. 6-M91, Principles and Practices of Electrical Coordination between Pipelines and Electric Supply Lines.
Planting vegetation which grows to a maturity height over 4 metres is not permitted on the ROW. These shrubs should be planted in such a way as to not impede access to the transmission towers. An area of 15 metres around transmission towers should be kept clear of shrubs.
- Buildings and permanent structures are not permitted on ROWs
- Flammable or hazardous materials may not be stored on ROWs
- Consideration should be given to minimizing the use of conductive (metallic) material where alternatives exist (e.g. fences)
If you encounter an issue during authorized work, suspend work right away.
- Contact with an overhead power line
- Risk to life
- Environmental risk
- Damage to an NB Power facility
Call one of the regional contacts listed on your authorization to get assistance. In the case of an emergency contact 911.