Transporting electricity
(continued)

Wood poles

Canadian power companies use more than 10 million treated wood utility poles in their transmission and distribution operations. Most of these structures are treated with chemicals that slow wood decay and provide protection from insects, pests and fungi. These chemicals include creosote, pentachlorophenol (PCP) and chromated copper arsenate (CCA). Although extending the life of the poles and lowering operating costs, these preservatives contain hazardous substances.

Different initiatives are under way to manage these risks. The industry is working with regulators and other stakeholders to develop alternative treatment approaches and to encourage responsible practices for the use, storage and disposal of treated wood.

Wildlife habitat

Construction and maintenance of transmission lines may destroy plants and animals or change their habitat. For example, trees used by rare birds for nesting may be cut down or soil erosion may affect rivers and wetlands that provide habitat. Impacts to wildlife species can usually be avoided by redesigning or relocating the transmission line. In some cases, transmission lines can be managed to provide wildlife habitat for birds and animals. Raptors such as osprey sometimes build nests in power poles. Power companies frequently construct nest boxes to relocate these and other bird species away from power lines to prevent electrocution and power outages.

Electric and magnetic fields

Health concerns have been sometimes raised when new transmission lines are proposed. Exposure to electric and magnetic fields has been studied since the late 1970s. These occur whenever electricity is used. The magnetic field is created when electric current flows through any device including electric wiring in a home.

To date scientific research has not found a causal link between EMF exposure and health effects. For example, the U.S. National Academy of Sciences concluded in a 1996 report that “the current body of evidence does not show that exposure to these fields presents a human-health hazard.”

Some questions remain about the possible relationship between EMF and certain human diseases such as cancer. However, a series of major animal cancer studies around the world has not produced evidence to support the idea that EMFs promote or stimulate cancer development.

The industry continues to monitor worldwide research on EMFs and supports further studies to answer remaining questions on potential health effects.