Keeping the lake at bay in Abbotsford

How an engineering marvel defeats gravity to keep Sumas Prairie dry

Abbotsford's Barrowtown Pump Station is the second-busiest facility of its kind in North America.

Abbotsford's Barrowtown Pump Station is the second-busiest facility of its kind in North America.

The draining of Sumas Lake marks a major turning point in the development of the Fraser Valley.

A century ago, a large lake occupied much of the space between the small communities of Chilliwack and Abbotsford. It had been used for millennia by First Nations to hunt, fish, and move around the area. But for settlers, it was a barrier to the development of the region.

And then, in the early 1920s over the span of just a couple years, that obstacle was gone. Instead, the Vedder Canal and a pump station helped drain hundreds of square kilometres of fertile farmland, turning the region into B.C.’s agriculture capital.

Yet, the work of keeping Sumas Prairie dry will never be finished.

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You can’t see it from Highway 1, but squeezed between the highway and Sumas Mountain in the eastern stretches of Abbotsford, the second-busiest pump station in North America works day and night to keep the lake from returning.

The ocean may be miles away, but the area that was once Sumas Lake lies at or near sea level.

The Barrowtown Pump Station was built in the early 1980s for $27 million, replacing a station that had successfully kept the prairie flood-free for six decades. Inside, one glimpses a mix of the old and the new, of both simple and complex technologies.

“If we were to turn off these pumps, the lake would resume all the way past Whatcom Road,” says Tim Henry, the city’s director of utility operations.

The Sumas Canal acts like an artery for the prairie’s drainage and irrigation system, which includes dikes that criss-cross the area that drain water collected from the fields, the surrounding hills and Abbotsford’s elevated urban areas. On some bright, sunny days, just one of the station’s four massive pumps is needed to move water from the canal two or three metres up and into the Sumas River, where the water then heads to the Fraser and eventually the Pacific Ocean.

Other times, particularly after a large storm, the four pumps work full out, moving an Olympic-sized swimming pool worth of water every minute.

Each pump boasts an engine that spins a cylinder, at the base of which a rotating capsule ingests water and forces it up, towards the river above.

Now 30 years old, Barrowtown costs around $500,000 a year to operate. For the city’s drainage and diking crews, the biggest ongoing challenge comes not from nature, but from humans and their trash.

A stray piece of plywood can back up the whole system, and can be difficult to remove when millions of litres of water are trying to head downhill. The solution is simple: get to the trash first. Before a storm, James Hill – the city’s works supervisor in charge of diking, drainage and irrigation, and the man in charge of day-to-day operations at Abbotsford’s pump stations – will increase the amount of water being pumped out of the prairie, drawing ditches down prior to the onslaught of rain.

Workers, meanwhile, head out to ensure that ditches, canals and culverts are flowing smoothly so the water can move towards the station. And yet, trash from the highway, wood debris and pots from farmers fields – among other things – all still end up at Barrowtown.

“It’s amazing. We get spare tires and so many garbage cans,” Hill says.

The other large risk comes from the station’s reliance on the power grid. If a blackout were to coincide with a major storm, just a couple days would be enough to cause a serious headache, or worse. The potential consequences are such that Barrowtown is second only to the hospital on BC Hydro’s priority list of local facilities to be restored to operation in the event of a large-scale outage. The station also has a huge, gleaming transformer already on site in case the existing one fails. Without it, the station’s operators would have to wait days for a new one to arrive, with the Sumas water levels gradually rising all the time.

That’s never happened yet. Instead, the pumps churn away, keeping Sumas Lake a memory.

“For somebody to come up with this idea amazes me,” says Hill.

A dark side to draining Sumas lake

The elimination of Sumas Lake in the 1920s changed Abbotsford, but it also had a negative impact on the Sumas First Nation, which used the lake both as a fish food source, and also to facilitate transportation and hunting.

“Some would say it was our shopping centre,” Sumas Chief Dalton Silver told The News in 2013. The draining of the lake was an environmental disaster, he said, and wouldn’t be allowed today.

The lake’s destruction saw a vital resource transformed into land for settlers, and the Sumas are pursuing compensation, although the process is long and unsteady.

Still, at the time, some of Silver’s descendants found the idea of draining the lake more laughable than worrying.

“Our ancestors more or less thought it was just crazy,” Silver said in 2013. “And some of them kind of laughed because what we heard is that they said these crazy people are going to drain the lake. It just wasn’t something our people looked at and though could really be done.”

 

 

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