The designer of the Norrish Creek Water Plant says the City of Abbotsford is to blame for the 2015 failure of a valve that led to more than $1.7 million in damage.
Earlier this year, the city filed suit alleging that designers Dayton &Knight had failed to “incorporate redundancies and fail-safe measures” that would have reduced the likelihood of a flood and limited the damage caused should one occur.
But in a response filed in late June, Opus International and Opus DaytonKnight Consultants – two companies created as a result of mergers involving Dayton &Knight – said the designers did nothing wrong and that it was mistakes by the city that led to the valve failure and subsequent damage.
Opus says Dayton &Knight designed the plant to treat up to 33.3 million litres of water per day with all needed redundancies included. But they say that in 2011, the city increased the plant’s capacity to 55 million litres per day, with the intent of another larger expansion at a later date. That expansion – which came less than three years after the plant’s construction – was designed by another firm.
Opus says the expansion resulted in alterations “contrary to Dayton &Knight’s design” and that they resulted “in a reduction in the safety of the plant.” Opus says the changes also reduced or removed redundancies that had been incorporated in the original design.
Furthermore, Opus said the city “failed to maintain and/or replace one of the plant’s control valves.” The city knew the valve was leaking hydraulic fluid but failed to investigate the problem and fix or replace it, according to Opus.
On March 27, the valve became stuck and couldn’t limit the water entering the plant, Opus said. The plant couldn’t cope with the amount of water entering, which Opus said was increased as the result of the modifications. The companies say a weir that had been altered was incapable of diverting excess water.
The companies also say the city should have had someone on site who could shut off the water inflow. Instead, they say the only person present was a security guard who didn’t respond to the failure of the valve. None of the allegations by either party have been proven in court.
Following the 2015 event, a second emergency valve was added at a cost of $90,000 to protect against a future flood.