Impact of line construction on environment

Impact of construction and operation of high voltage overhead lines on the natural environment

Impact of the OHL construction and operation in the environment essentially differs from each other as by scale and quality so by coverage of natural receptors under influence.

During construction and operation of OHLs main impact is on:

  • Water Bodies - Streams and Rivers
    • Sedimentation caused by sediment laden runoffs due to soil excavation and disturbance by project vehicle and other construction equipment along access roads and right-of-way.
    • Placement of towers in floodplains can impede flood flows and produce flooding in upstream areas.
    • Contamination caused as a result of in channel spill or transportation of pollutants spilled on ground by surface runoff.
    • Contamination caused as a result of in channel spill or transportation of pollutants spilled on ground by surface runoff.
  • Air Quality
    • Air pollution with noxious matter on the construction phase
    • Emission from building machinery
  • Geology, soils
    • Soil compaction and rutting by vehicle and other construction equipment along access roads and ROW
    • Clearing of trees and shrubs make the soil more susceptible to erosion and mass movement
    • Blasting for tower foundations may trigger mass movement of soil, or avalanches in high snow areas.
    • Soil contamination from the use, improper handling and spills of hazardous materials (fuels and lubricants, paints, etc.), which could be used during the construction and maintenance works.
    • Vegetation control techniques that use herbicides can contaminate the soil.
    • Soils excavated for foundations may be exposed to wind and water impact for long periods
    • The placement of poles on unstable areas, or areas with geohazard activation risk can cause landslides
  • Potential impact on land use
    • Physical displacement of households
    • Permanent or temporary loss of croplands and grasslands
    • Forest clearing for construction and conducting works, and OHL safety
  • Potential impact on biological environment
    • Permanent loss of forest habitats for wildlife due to RoW clearance, tower installation, conductoring and construction of access roads
    • Fragmentation of forest habitats due to RoW clearance, tower installation, conductoring and construction of access roads
    • Introduction of invasive species into forested ecosystems
    • Temporary loss of habitat§  Destruction of dens/ nest, injury/mortality of animals during construction and maintenance activities
    • Avian and bat collisions/ electrocution from contact with power lines.
    • Damage/removal of vegetation due to RoW clearance, construction works and machinery operation
  • Potential impacts to local population, project workers and general public
    • Potential health risks due to noxious factors (noise, flue gasses, dust)
    • Potential safety risks from project machinery movement
    • Propagation of communicable disease from introduced workers
    • Safety risks due to falling of towers or live cables
    • Aircraft safety risks for airports in close proximity to OHL