New standards cause advisories for those receiving slightly cloudy lake water
A water-quality advisory was issued May 2 by the Town of Osoyoos for customers in the adjacent Irrigation Systems 8 and 9.
The warning remained in effect as of Monday, May 8.
However, officials said people living outside those areas were not affected. The Town has authority over the Irrigation District, which draws its water from the lake.
People living in the affected area are those who live in the rural Osoyoos area and receive an Osoyoos Water District bill (formerly called SOLID “ South Okanagan Lands Irrigation District). There are also 60 properties on this water-district supply inside town boundaries “ on the west side of Highway 97, south of the Husky gas station.
The advisory stated that due to increased turbidity (cloudiness), the Town and Interior Health recommend that children, the elderly, people with weakened immune systems, and anyone seeking additional protection drink boiled water or a safe alternative.rnThe advice went a step further to caution that water intended for washing fruits and vegetables, making beverages or ice, or brushing teeth, should be boiled for one minute.
The turbidity index was rated fair for system 8 and 9 users, which raised concerns about its safety and questions about what risks are associated with drinking the water. According to the Town's news release, health risks increase as turbidity rises.
Contaminants such as viruses, bacteria and parasites can attach themselves to the suspended particles in turbid water.
These contaminants can then interfere with disinfection, limiting chlorine's ability to remove or inactivate the contaminants, the release stated.
Public Works Director Ron Doucette said recent changes to Interior Health's standards for turbidity resulted in last week's Water Quality Advisory.
The lake hasn't changed, and the Town is on wells, so our drinking water is in good shape. What has changed are the regulations and standards, said Doucette.
He explained that last year, nephelometric units (NTU) registered at 5 and under were acceptable. Under the new regulations, if turbidity levels exceed 1 NTU, Interior Health and the affected municipality must issue a Water Quality Advisory. He said last week that NTU were measured at approximately 1.5.
Turbidity levels below 1 NTU are rated good, between 1 and 5 are rated fair and above 5 are rated poor. Once units exceed 5, a Boil Water Advisory is issued.
Doucette said turbidity testing is done on an ongoing basis. Water flows through a monitoring system and the quality is continually recorded.
There are also weekly tests to measure coliform and other bacterials in the water system, which Doucette said have all been perfect.
He adds that only through a major and expensive filtration system upgrade could turbidity levels be maintained at 1 NTU or below.
We don't want to panic people. These kinds of advisories are a joint effort between the Town, Interior Health and the media to inform the public about water quality. And again, if the regulations hadn't changed, we would have had no need to issue this advisory.rnMore information about turbidity can be found in the Spring 2006 issue of Water News, a pamphlet produced by the Town of Osoyoos.
