While the water may be back on, there are still questions concerning what happened.
“As you’re aware, the plant had issues. So that caused four major breaks within town,” said Cris Burns, CAO for the town, during the May 1 regular meeting of Vauxhall council, on what had happened at the Vauxhall Water Treatment Plant.
On the morning of April 27, around 9:30-10 a.m., the town received word of four water main breaks — one by the watering shed at the ball diamond going into the parking lot, one by the Wendy’s Drive In parking lot where the semi-trucks park, one by Rowland Seeds right across from the town shop and the biggest one by Bow River Gas Co-op going into the research station.
All four breaks were reported at roughly the same time.
That morning, operators at the water plant were doing a routine test on the different, systems, including one on the back-up generator. When switching power from the utility service to the generator, the Uninterruptible Power Supply (UPS) unit failed, causing the failure of three programmable logic computers, which control all functions in the plant, including water distribution.
Operators had commenced with emergency procedures, including manually operating a distribution pump, but bypassing automated pressure sensors caused the system to become over pressurized, causing the breaks within the town.
“Sometime in the last month, before Thursday’s (April 27) test, the UPS system had failed, and we weren’t aware of that failure until the switchover from utility to generator power occurred. What happens is when we switchover, the operation of the control modules and the control systems operate off of this UPS system only, and then there’s a period of time where it switches from utility to generated power, that the UPS system carries the entire load of the operating system, and that’s when the failure occurred,” said Derrick Krizsan, CAO for the Municipal District of Taber.
“So sometime in the last month, something went haywire there, and it wasn’t apparent until the UPS system was entirely responsible for the electrical supply to our control systems.”
By 2:30 a.m. on April 29, the main by the Bow River Gas Co-op was repaired. The second repair was at the one by the ball diamond, followed by the one by the town shop, and in the course of the next few days, the remaining breaks were repaired, with the fourth and final break being repaired on May 1.
“The fourth leak was fixed (May 1). It was left for the weekend because we could isolate the block that it was on, and there was nothing that was servicing that block. It wasn’t affecting anybody’s services so we left that till today,” said Curtis Cawley, public works foreman for the town.
The water remained safe to drink but due to the limited production users were asked to limit their consumption for emergencies.
Water conservation notices went into effect that same day while the bulk of the work was being done, with water temporarily shut off late Thursday evening until 1 a.m. Friday morning.
By 5:30 p.m. on April 28, the water plant was reported as being back at operating full capacity and truck fills reopened, but on April 30 in the early afternoon the conservation notice went back into effect, due to pressure problems from the plant due to a power failure. The conservation notice was finally lifted on Monday, May 1.
“There was a failure again of the UPS system,” said Krizsan. “What they did was restarted the plant, and there have been no further incidents since that time. However, we have had the plant manned 24 hours a day by operations staff.”
Throughout the ordeal, the water remained safe to drink but due to the limited production, users were asked to limit consumption.
The water level at the plant never fell below 1,300 cubic meters, or 55 per cent capacity. Burns said that as they didn’t go to a zero or negative pressure in the system, no flushing of the lines was required.
“We didn’t go into a zero pressure, because it was dribbling, but a lot of people wouldn’t be able to fill a glass fast or have a bath or anything like that,” said Burns.
“They would have been without water to actually access water to enjoy a bath or anything like that, you couldn’t do any of that. Just enough pressure to cause a dribble.
“In a residence, they would consider it off.”
Burns warned council that despite the fixes to the lines, they may experience another similar problem this winter.
“What I was told by the contractor was this happened in the regional system up north, where they had a bump like this, and in the next, this following winter, they had a quite bit more, because of this pressure burst causing more issues,” said Burns. “So we may see more issues yet this winter.”
On Monday, electrical and engineering consultants informed the Vauxhall and District Regional Water Services commission that a faulty Uninterruptible Power Supply unit was the cause of the issue, and needed to be replaced. A new one is expected to arrive and be installed on Friday, May 5.
“It’s a bit like when your computer crashes and you can’t get your printer to work. Computers are great when they work, just not too much fun when they don’t,” said Brian Brewin, reeve of the M.D. of Taber, of the problem.
“It’s a relatively new plant, that’s what’s ironic; it’s one of our newer plants.”
As receipts are still coming in, it is currently unclear how much fixing the problems will cost, although the Krizsan says they should find out within about a week. The replacement UPS — a brand new unit — will run about $10,000 plus labour.
Additionally, the plant needs to be manned 24 hours until it is installed. No further issues with the water supply or with the plant have been reported.
As the routine tests occur once a month, the UPS would have had to have failed in the past once before the latest test.
The UPS unit was brand new to the facility since it opened in 2013, and should have had a few more years on it before it needed to be replaced.
The Vauxhall Water Treatment Plant services the town of Vauxhall, hamlet of Hays, hamlet of Enchant and surrounding areas through truck fills. It is managed by the Vauxhall and District Regional Water Services Commission run by the M.D. of Taber and the Town of Vauxhall.