Why wooden electricity poles portends health, environmental danger
Utility (electric) poles are a common feature of our everyday landscape. They support the wires that bring electricity from the power company to our homes.
The trend is fast giving way with modern town and estate planners preferring that wires are buried underground in new developments. Nevertheless, there are still several million of utility poles in service in Nigeria with individual developers especially in rural and semi urban areas preferring wooden poles for the single purpose of cost.
The Nigerian Electricity Management Services Agency (NEMSA) recently warned Distribution Companies of Nigeria (DISCOs) to stop the use of wooden poles in their operations. They also cautioned them against bad “networks” installation, which it claimed had been responsible for electrical accidents that have claimed several lives.
Managing Director/ C.E.O and Chief Electrical Inspector of the Federation (NEMSA), Mr. Peter Ewesor, who was in Benin City, on a sensitization tour and visit to the DISCOs, also closed down shops in the business of selling wooden poles in the state, assuring that persons dealing in substandard, electrical systems, particularly wooden poles will be arrested and prosecuted.
NEMSA, a technical inspectorate set up by the federal government to enforce technical standards in Nigeria’s electricity industry, stated that its decision to outlaw the use of wooden poles by both the 11 electricity distribution companies (Discos) and other users in the country was occasioned by prolonged abuse of the country’s approved standards for manufacturing of wooden poles by producers.
Ewesor explained that there are no longer quality wooden poles manufacturing company in Nigeria, hence the production and deployment of substandard wooden poles which contribute to instances of electricity accidents.
Beyond the non production of quality wooden poles in Nigeria, a research at RMIT University has proven conclusively that wooden poles used for electricity distribution deteriorate with age and that their electrical performance worsens over time.
Fires caused by leakage current in wooden poles used for electricity distribution are a major problem for power distribution companies globally.
The Research by Dr Sachin Pathak, in the School of Electrical and Computer Engineering, investigated the behaviour of leakage current on wooden structures of various ages.
His findings reveal that, Leakage current flow happens where current leaks through the insulator, due to deposits of salt spray, sand or chemical pollution on the insulator surface, under extended dry weather conditions with light rain and high humidity.
He further revealed that excessive activity of leakage current generates enough heat to ignite ageing wooden structures, particularly where there is contact between the wood and metal surfaces of the power pole.
According to Western Wood Preservers Institute (1996), With proper maintenance, the average lifetime of a wood utility pole is typically 30 to 40 years, but as poles age, the effects of initial preservative treatments wear off and the preservatives must be re-applied.
Tobi Aduroshakin, a Building Engineering expert, argues that the majority of wood poles in service today in Nigeria have not received, nor is it scheduled to receive, what is suppose to be a repeated applications of preservative.
He said: “During the time a utility wooden pole is in use, water acts as a medium for preservatives leaching from the wood into soils and groundwater. Leaching rates vary by both type of wood and chemical, the standard of application applied as well as well as the type of soil the pole is rooted in.
According to a fact sheet on chemically treated wood presented by the ‘beyond pesticide/National Coalition against the misuse of Chemical pesticides based in Washington, United State, “wood preservatives chemically used to treat poles contain dangerous chemicals, including dioxins which harms human health and the environment.”
In 2001, the European Union severely restricted the sales and use of creosote(a chemical formulation used to preserve wood) after an EU scientific committee concluded from a recent study that creosote has a greater potential to cause cancer than previously thought.
In February 2003, the U.S. Consumer Product Safety Commission announced that it found that that some children may face an increased risk of developing lung or bladder cancer over their lifetime from playing on playground equipment made from CCA pressure-treated wood. This risk is in addition to the risk of getting cancer due to other factors over one’s lifetime.
Experts have therefore recommended that Poles made of alternative materials such as recycle steels, concrete, composite, or the burying of lines, are all alternatives to wood poles that are currently used.