Carline's concerns result from an April 12 provincial amendment to the Safe Drinking Water Regulation Act, one of the last actions of the previous legislature. The new regulations replace somewhat looser guidelines and concern themselves mostly with turbidity, the presence of suspended solids that can give water a cloudy look. The result can be gastrointestinal illnesses including, in extreme cases, giardia and cryptosporidium, the deadly disease that struck North Battleford. Turbidity is measured in NTUs, or nephelometric turbidity units. Greater Vancouver's previous guidelines allowed for counts as high as five NTUs.
Filtration is necessary to meet that standard.
But Doug Neden, the GVRD's administrator of water treatment and research, points out some advantages of Vancouver's water supply compared to others. North Battleford is on the North Saskatchewan River. That river goes through cities and farm land and has a number of sewage discharges. It is much, much more susceptible than we are with our closed watersheds. That's why a risk assessment a few years ago indicated that our risk of cryptosporidium was really very, very low.