Jan. 15, 2020

No lead problem in Nanaimo's drinking water

The television news series about lead in drinking water throughout the country was enough to raise eyebrows, especially since I was on city council when the Nanaimo water treatment plant was built.

First, we can all rest assured that Nanaimo’s drinking water and its infrastructure is safe and does not contain lead. Bill Sims General Manager, Engineering and Public Works, explained how the national conclusions were reached through media and journalism schools. The students knocked on doors of older homes and sampled tap water for lead. 

The main source of lead in drinking water is old plumbing, lead solder and water sitting in plumbing for extended periods. Homes built more than 40 years ago are at greater risk because they are more likely to have lead plumbing. Lead was used as a material for water pipes until 1975 and in solder used to join pipes until 1986. Until 2014, faucets and hardware could contain up to eight per cent lead. Note that galvanized steel pipes can also leach lead into drinking water.

As an example, schools run cold water taps for several minutes to bring fresh water in, after school holidays, which is usually effective in flushing elevated lead levels. That does raise a question though – is there any reason for not upgrading the plumbing in schools?

Buildings on private property which may have old plumbing may have lead in the plumbing. However, the good news is that the City adds soda ash, which elevates the level of pH at the water treatment plant as corrosion control. This should go a long way to ameliorating the problem of lead leaching into the water on private properties.

Nanaimo’s water treatment plant adds soda ash to raise the pH of the water and controlling corrosion in old plumbing. Higher pH water is not acidic but lower pH water can leach lead from old plumbing. Modern plumbing fixtures and solder are generally lead-free, says Sims.