Engineering report identified risk of over-consumption in Saint John west water supply
BGC Engineering report assured city that wells had enough to safely meet current demand
A 2015 report on Saint John's west side water system shows BGC Engineering identified the risk of saltwater getting into the water supply as a possibility down the road.
Residents learned Monday that six west Saint John neighbourhoods would be switched over to the east side water system for a while because well levels in the South Bay well field had dropped one metre below sea level.
There isn't enough water to support the demand, and there's a long-term risk of saltwater intrusion in the wells, the city said.
Saint John is now taking legal action against BGC Engineering to try to recover costs of what the city calls bad advice from the national firm.
In 2013, the city hired BGC Engineering to help it develop a groundwater system for west Saint John. At the time, residents were getting their water from Spruce Lake.
The March 2015 hydrogeological report obtained by CBC News shows the engineering firm determined the wells could supply the west side if residents used an average of 12.5 megalitres of water a day.
At the time, Saint John west was using an average of 11.1 megalitres a day, so BGC said there was enough water in the well field to meet the demand.
But BGC warned that if people on the west side used more water than originally expected, the water in the wells would be in danger of falling below sea level. The report identified 15 megalitres a day as the start of a risky level of consumption.
Brent McGovern, the city's water commissioner, says average water use has not increased since the switch to the South Bay well field, so the well levels should not have dropped below sea level.
Forecast supply would hold
"At the demands we're at on the west system, the engineering firm identified that indeed the water levels would remain one metre above sea level," he said.
The report prepared by BGC was part of a larger environmental impact assessment required for the project to go ahead.
The city says BGC's recommendations about the risk of saltwater intrusion were taken into account during creation of the criteria for how the wells would operate.
In an emailed statement, the city provided numbers showing that since the new system started in September 2017, the wells have operated on a daily average below 12 megalitres.
Mayor Don Darling said he couldn't comment on the BGC report, but he reiterated what McGovern said about pumping levels.
"We were pumping below the levels that we were told that we could pump to," Darling said. "And even with that we still have a problem on our hands."
Tested for a year
The BGC report covers fieldwork that took place between 2013 and 2015 to determined whether the South Bay area held a viable groundwater source for west Saint John.
It notes that the area was ranked highly for its potential to generate water, but that it was also conveniently placed close to existing infrastructure for Spruce Lake.
The company test-pumped the wells for a year to determine whether they could sustain the projected demand from customers on the west side.
McGovern said the conclusion the report presented to the city was that the wells would have enough water supply to avoid dangerous levels.
"It was independently reviewed by two experts," he said. "They also arrived at the same decision, or same recommendation, that these wells could more than meet the needs of west Saint John."
In an emailed statement earlier this week, BGC said it is aware of the concerns related to the water levels in the South Bay well field. The firm also said it is confident the advice it gave the city was appropriate. The firm noted the cause of the issues related to the water levels hasn't been determined.
Looking for solution
The city is hoping that by removing some of the demand, the wells will be able to recharge and return their water levels to above sea level.
To achieve this, the city will be moving two-thirds of west Saint John residents to an east side water source as an interim solution.
"We need to realign the demand and ensure that the demand on the wells meets the needs of all of the well fields such that it can be sustainable in the long term," McGovern said.
The City of Saint John has cancelled its contract with BGC.
"We were told after their pumping test that we had ample water supply," Darling said. "What we believe today is that information [from the company] was bad advice."