Recently detected bacteria in the Olalla water supply has led the Regional District of Okanagan Similkameen (RDOS) to direct all residents to boil their water until further notice.
The notice, which was issued on April 24, directs all residents to boil any water prior to use for drinking, food preparation, cooking, ice making or tooth brushing.
According to the RDOS, recent water tests showed poor water quality and bacterial growth within the system. The release does not state what kind of bacteria is growing, and the RDOS did not elaborate when contacted for comment.
A review of releases from the RDOS show that since September 2024 the system's water mains have been flushed three times and just as many months of temporary chlorination of the system.
Prior to that, there was one release in 2023 regarding water main flushing and a little more than a week of chlorination, and one release in 2021 regarding water main flushing and chlorination.
In addition to the boil water notice, the RDOS issued a separate request to all residents on the system to check their plumbing for any potential cross-connections or opportunities for household water to make its way back into the water system.
“RDOS staff are in the field investigating and will work diligently to expedite the removal of the Boil Water Notice," said Allen Fillion, the RDOS's managing director of development and infrastructure services, in an email.
The RDOS had previously inspected the water system's infrastructure in 2025, but the inspection did not discover the source of the bacteriological contamination.
According to a post to social media by area director Tim Roberts, one theory is that there may be one or more large leaks on private property, which is backed up by the Olalla system having the highest per-capita water usage in the RDOS.
A cross-connection could be any actual or potential connection between the drinking water system and a non-treated source.
It could include backflow from an untreated line down the drinking water pipes, and most often occurs at properties that are connected to the water system and to a privately-owned well.
More information on cross-connections can be found on the RDOS website at rdos.bc.ca.
Any residents who suspect they have a cross-connection on their property are asked to contact the RDOS. Staff will inspect your system at no charge.
The main goal is to find the source of the contamination and return the water system to its previous state.
For further information, or to report a suspected cross-connection, contact RDOS Public Works at 250-490-4106 or 250-490-4135 during regular business hours, Monday to Friday.
