New water filtration plant delivers high quality drinking water in Union Bay
Residents on the east side of Vancouver Island in the Union Bay Improvement District (UBID) are the first in the Comox Valley to get their drinking water from a multi-barrier water filtration plant. UBID draws its drinking water from Langley Lake via a two-kilometer transmission line where previously chlorine had been the primary method to disinfect the water. An underground reservoir stored the water before sending it via gravity feed to the distribution system. With only one barrier to protect the drinking water, the former treatment system was left vulnerable to events that could create turbidity in the watershed.
Potable water standards are enforced by Island Health through a Permit to Operate that outlines the operating terms and conditions for each individual water system. The water treatment system in Union Bay no longer met the terms outlined by Island Health and was apparent that an upgrade to the system would be required.
UBID manages the water withdrawal license issued by the Ministry of Forests, Lands and Natural Resource Operations. In partnership with Mosaic Forest Management, the watershed is monitored for activity and any changes to water quality and quantity.
In 2007, Island Health adopted the 4-3-2-1 policy aimed at ensuring consistent standards for all surface water supply systems on Vancouver Island. The policy requires surface water supply systems to maintain the following treatment specifications:
- 4-log (99.99 per cent) removal/inactivation of viruses;
- 3-log (99.9 per cent) removal/inactivation of Giardia cycts and cryptosporidium oocysts;
- 2 treatment processes, usually filtration and disinfection; and
- 1 NTU turbidity (maximum) in finished water.
Union Bay’s water system required an upgrade to meet these standards. With the use of chlorine as the only treatment method used to treat the water, the introduction of a filtration process was a necessary step to meet the regulatory standards. In 2014, the Permit to Operate required the construction of a water treatment plant in order to meet Island Health’s water quality objectives outlined in the 4-3-2-1 policy. UBID has worked diligently with Island Health to fulfill these Terms and Conditions and the new water treatment plant has been providing water to all end users as of May 15th, 2020.
The construction of a new water treatment plant for Union Bay started with the acquisition of the land, a $1 purchase from Union Bay Estates in 2018. Once land was secured, engineering firm Koers And Associates Engineering Ltd. was retained to develop the scope of work and conceptual design and produce the preliminary design drawings for the request for proposal. After a full review of all submitted proposals, Ridgeline Mechanical Ltd was awarded the construction bid with AWC Process Solutions Ltd. supplying the treatment portion of the water treatment plant. Once the plant was built, there was a commissioning period to ensure that the plant was operating as per designed. The facility is fully operated by certified UBID public works staff.
To view the construction reports, click here.
Water quality is significantly improved compared to the water quality from the former system. The new facility added several additional treatment steps to deliver drinking water that exceeds provincial and federal standards. The first step in the process is the flocculation and coagulation of particles, step two is a dissolved air flotation (DAF) process to remove the organics and colour particles, step three dual media filters to purify the water, and then goes to the clearwell. From the clearwell, the addition of sodium hydroxide for pH adjustment and a 12% chlorine solution is added to ensure that the water satisfies, and exceeds, regulatory water quality standards/parameters. Chlorination and pH-adjustment add disinfection and corrosion control as the water travels through the distribution network.
Under current operations, filtered water is being sent to the clearwell at a turbidity level of 0.03 NTU. Anything higher than 0.3 NTU and the water is sent into the backwash cycle rather than to the clearwell and storage tank. The above-ground reservoir can hold up to 1,750 cubic metres, which has expanded the capacity of the of the old system by three times.
For a detailed description of the plant processes, click here.
Since the facility has been put online and providing water to the Union Bay Improvement District’s end users, staff have been testing the water quality daily at the plant and taking weekly micro-biological samples to the accredited lab. The entire system is monitored 24/7 for all processes, functions and water quality monitoring. The new system is providing the highest quality water possible.
Due to WorkSafe considerations for staff there are no public tours being offered at this time.
Water Treatment Plant Project
After years of planning and coordination, the Union Bay Improvement District (UBID) has completed a new water treatment facility to service 690 properties in the community – allowing a regular boil-water advisory by Island Health to be lifted.
The new plant incudes a water filtration system, enabling it to meet current provincial drinking water guidelines.
Thank you to all who have worked for many years to reach this important milestone for our community.
For More Information:
- Press Release, June 11, 2020: Union Bay’s new water treatment plant now complete.
- Water Treatment Plant – Notice of Pressure Change
- UBID Project Backgrounder – December 2019
Additional Information and Project Background
Water Treatment Plant Project Updates:
WTP Construction Updates
- Construction Report for Mar 13
- Construction Report for Mar 6
- Construction Report for Feb 28
- Construction Report for Feb 21
- Construction Report for Feb 14
- Construction Report for Feb 7
- Construction Report for Jan 24
- Construction Report for Jan 10
- Construction Report for Dec 16
- Construction Report for Dec 6
- Construction Report for Nov 29, 2019
- Construction Report for Nov 22, 2019
- Construction Report for Nov 15, 2019
- Construction Report for Nov 8, 2019