Water System

The Norrish Creek water source currently provides approximately 85% of the system supply. Existing water licenses allow for an annual average withdrawal of 92 MLD with a maximum amount of 141.5 MLD.

Dickson Lake, located approximately 10 km upstream of the water treatment plant, serves as a storage reservoir to supplement flow to Norrish Creek. The lake was formed thousands of years ago by a landslide. A dam was built in the 1980’s to allow for controlled release of water. Two pipes extend through the dam allowing for gravity release, while a floating pump station allows for discharge from the lake when the level is below the outlet pipes. The lake is generally full from December to June, with varying degrees of drawdown experienced from July through September, and refilling in October and November. Release of water from Dickson Lake is governed by the water licenses, which require that flow from the lake slightly exceeds the amount withdrawn from Norrish Creek to ensure sufficient fisheries flows downstream of the intake.

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• Current flow conditions in Norrish Creek
• Dickson Lake Level Graphic

The dam at Cannell Lake was built in the 1950s. Flow from the lake is provided by gravity/siphon discharge pipes, with a floating pump station allowing for pumping from the lake if the level drops below the outlet.

Cannell Lake provides approximately 10% of the annual system supply. Existing water licenses allow for annual average of 11.8 MLD and maximum day withdrawal of 69.1 MLD.

The Cannell Lake watershed is 2.1 km². Water from the lake is not filtered, but the water is disinfected by UV and chlorinated about 1 km south of the lake. Ammonia is then added at a point 7 km further south, producing chloramines. Overflow from the lake discharges to Cannell Creek, into Cardinalis Creek, and then Stave Lake.

At a top water level of 278 m, the Cannell Lake system is at a substantially higher elevation than the Norrish Creek system. This allows for servicing of higher areas in Mission. When the Norrish system is off-line due to maintenance or other events, the Cannell system is utilized at a higher capacity to compensate for the reduced output from Norrish.

• View the Cannell Lake Watershed Control Program Plan

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There are currently 15 groundwater wells in the south region of Abbotsford that provide about 5% of the annual system supply. The wells are generally only operated during peak consumption periods of the year or when the Norrish Creek supply is off-line.

In 2007, four new wells were drilled adjacent to Bevan Avenue, near Mill Lake. Provincial regulations require that new well fields exceeding a flow of 75 l/s (6.5 MLD) undergo an environmental assessment. The Bevan wells have a capacity of 290 l/s (25 MLD), but could not be operated at full capacity until authorized by the province.

An Environmental Assessment Certificate was issued in May 2011 allowing full use of the wells. Conditions of the certificate indicate that, other than for emergency and maintenance, the wells can operate from May through September, but cannot exceed an overall annual volume equivalent to 100 days at full capacity (2505 ML). It was also required that mitigation wells be constructed to augment groundwater flow to Horn Creek and Boa Brook and to mitigate potential impacts to the Clearbrook Waterworks District.  Numerous other notification, consultation, and monitoring commitments were appended to the certificate.

The regional system has two storage reservoirs. Maclure Reservoir is located in the west region of Abbotsford and has a capacity of 28.6 ML. Mt. Mary Ann Reservoir, on the east side of Mission, has a capacity of 6.8 ML. The combined total volume of 35 ML is approximately equal to a tank the size of a soccer field with a height of 2.5 stories (7.5 m).

The storage capacity of the regional reservoirs (35 ML) is only 25% of the maximum day demand experienced in the system (139 ML), thus does not provide long term storage. The purpose of the reservoirs is to provide for flow balancing and emergency storage. During high consumption hours, the system demand exceeds the capacity of the sources. Reservoir levels lower during the high demand times of the day and re-fill during the night when demand is lower. Likewise, reservoir storage is used during emergency firefighting situations when additional demand is placed on the supply system.

There are approximately 95 km of transmission mains that deliver water from the supply sources to major distribution points or reservoirs. Five bulk water meters are used to calculate the ratio of flow between the municipalities (these meters were replaced in 2011). There are two river crossings in the transmission system: one near Hatzic Lake (900 mm diameter) and one near Gladwin Road (600 mm diameter).

The City of Abbotsford will be operating the Bevan Avenue Wells at the southwest corner of Mill Lake Park as needed until September 30 as per the conditions of Environmental Assessment Certificate (EAC) #W11-01. The EAC allows the City to operate the wells between May 1 and September 30 and for maintenance and emergency purposes outside of the operational dates. 

View the Annual Monitoring Report - Part 1

View the Annual Monitoring Report - Part 2

View the Annual Monitoring Report - Part 3

View the Annual Monitoring Report - Part 4

View the Annual Monitoring Report - Appendices