Watermark > Winter 2002/03 > Features: Fraser Valley Regional District Norrish Creek Water Treatment Plant

Features

• Canfor Ensures Safe Drinking Water
• Norrish Creek Water Treatment Plant
• Kelowna Wins Provincial Award
• BC’s Drinking Water Action Plan Update
• BCWWA Course Calendar (for current calendar)
• Water Wise—Groundwater Protection Program
• Peachland Sewage Systems Get Funding for Expansion
• Canada Makes E. Coli Key Water Quality Indicator
• Provincial Government Launches Comprehensive Review of the Waste Management Act

Fraser Valley Regional District Norrish Creek Water Treatment Plant

By Allan Kraus, Fraser Valley Regional District, C.Tech.

The official opening of Stage 1 of the Fraser Valley Regional District’s Norrish Creek Water Treatment Plant took place on Saturday, October 5, 2002. The official dedication was held at the site located about 10 km northeast of Mission. Guests from the Regional District, Municipalities of Abbotsford and Mission, and both the federal and provincial governments were in attendance. The public was also invited to view the facility and many took advantage of the opportunity.

From left to right: Sean Brophy, Engineering Project Director, Executive Vice President of Dayton & Knight Ltd.; Mike Darbyshire, Manager, JAMES Plant & Central Fraser Valley Water System; Terry Raymond, Chairman, Fraser Valley Regional District; Allan Kraus, Superintendent, Water Supply Services; Mayor Abe Neufeld, District of Mission; George Ferguson, Mayor of Abbotsford& Chairman of the Central Fraser Valley Water Commission

The Central Fraser Valley Water Commission is the bulk water supplier to the City of Abbotsford and the District of Mission, with a total equivalent population of approximately 180,000 people. The primary water supply source is Norrish Creek, which is situated at a high elevation, minimizing pumping costs. The quality of the Norrish Creek water is excellent as a rule, but does deteriorate in the spring and fall during high runoff periods.

To meet increasing demand and stringent water quality requirements, the District adopted a long-range treatment program in 1989 that included the following:

• Construction of the sand filtration plant with a capacity of 90 ML per day;
• Construction of a membrane treatment plant in 2003 that has been designed to be expanded in stages, up to 108 ML per day;
• pH correction to reduce corrosivity of the water.
• Stage 1, the 90 ML/d slow sand filtration plant consists of:
• 4 filters with a total sand area of 10,000 m2
• 2.3 ML (500,000 gal) capacity clearwell
• control valve building
• chlorination system

The slow sand filtration plant is very straightforward. No chemicals are required for its operation, and at this site, pumping is not required. For these reasons the Norrish Creek Water Treatment Plant is very cost effective.

Slow sand filtration was developed almost 200 years ago in England. Where raw water quality and system size are suitable, it remains an attractive treatment technology and is still used quite extensively. It is simple, requires no knowledge of coagulation chemistry, yet is highly efficient in the removal of parasitic cysts, bacteria and viruses. Solids are removed almost entirely in a thin layer on top of the sand bed. This layer, composed of dirt and living and dead micro- and macroorganisms from the water (the schmutzdecke or dirty skin) becomes the dominant filter medium as the filter cycle progresses. When the head loss becomes excessive, the water layer is drained below the sand surface and the top layer (2.5 cm) is scraped off. The filter bed is then put back into operation and a new filter cycle commences.

A SCADA controlled automatic system is used to monitor and control the operation of the plant. An alarm system will alert the operations staff when any necessary remedial action needs to be taken. The 27 ML/d Norrish Creek Membrane Treatment Plant is currently being designed and will be constructed in 2003. The design is based on the expansion of the plant in 27 ML/d modules to an ultimate capacity of 108 ML/d.

Unlike slow sand filtration, membrane filtration is truly a 21st century technology. The amalgamation of these contrasting systems of treatment will result in a unique water treatment plant that is both innovative and very cost effective. ¦

Project Team:

Owner: Fraser Valley Regional District
Engineers and Project Managers: Dayton & Knight Ltd.
General Contractor (Stage 1): Westpro Constructors Group Ltd.
Membrane Suppliers (Stage 2): Zenon Environmental Inc.