Puslinch councillors have been told that one of the biggest threats to municipal water supplies for the City of Guelph is the reduction of recharge areas and increased water demands resulting from the city’s own growth.
One of Guelph’s main water sources that is considered “at risk” is the Arkell Springs well system, located in Puslinch Township.
On Aug. 15, Grand River Conservation Authority’s source protection program manager Martin Keller updated Puslinch council with respect to the Guelph/Guelph-Eramosa water quantity policy development study.
Considering current and future water takings under future land use and drought conditions Keller said there are significant risks associated with the Queensdale and Arkell 1 wells serving Guelph.
Those risks suggest that without changes those wells may not be able to continue pumping in the future (2031) under future land use buildout and drought conditions.
Keller explained that one of the greatest impacts to municipal wells – are other municipal wells.
He said the Queensdale well and several Arkell-area wells have a significant impact upon themselves.
Keller explained the Arkell system is ranked as a single entity because the wells are located close together.
He stressed, “there are no problems under existing conditions, but the modelling predicts there could be problems down the road.”
Keller stated, “Individually, the majority of non-municipal water taking has little influence on water levels in municipal wells except for Dolime Quarry, which has a 50 per cent impact on the Membro well.”
He said all other permitted non-municipal water taking has a much lower impact to individual municipal wells.
Keller noted that all other permitted takers exert 10% influence on the municipal wells including:
– combined influence of recharge reduction from land development – 9%;
– Gay Lea – 2% drawdown at Emma;
– Nestlé – 1% drawdown at Burke; and
– combined influence of all domestic wells – 1%
Neither of the wells cited as being at significant risk are listed as being impacted by Nestlé Waters operations.
Keller said the threats impact on municipal wells is expected to be limited by comparison.
Keller said a number of different measures were investigated including adjusted well pumping rates, well locations and other conditions to reduce significant risk levels.
He noted the following scenarios were successful in the modelling scenarios to reducing the risk to municipal wells:
– pumping optimization with demand reductions through conservation programs;
– pumping optimization with addition of new municipal wells; and
– pumping optimization with cessation of dewatering at Dolime Quarry (scenario 7).
Keller said that the study also looked at what might happen with growth in non-municipal water use.
Under annual climate conditions that are average or below average, all municipal wells could meet future pumping rates, Keller said.
However, he added that under drought conditions, non-municipal non-dewatering takings at permitted maximum rates predict that municipal wells will not meet future demand.
As a result, Keller said the model suggests that permitted maximum rates need to be reviewed.
He noted the current non-municipal, non-dewatering permitted takings may be able to increase by approximately three times the current amount before impacts are predicted at municipal wells under drought conditions.
This assumes future conservation targets at municipal wells are achieved, he clarified
Keller said Guelph’s continued growth and additional water demands will add stress to local water resources.
Collective water resource management by municipalities, the conservation authority and the province is needed to ensure municipal drinking water is sustainable and other water uses (such non-municipal takings, surface water flows, domestic users) have sufficient water to meet the respective needs.
He said one of the considerations could be a move from first-come-first serve, to a more prioritized concept, which would allocate water use to municipalities first.
“That is something this government has opened the door to,” Keller said.
He noted policy framework and approaches are to be brought to the Lake Erie Region Source Protection Committee in early October with a drafting of water quantity policy text expected to begin in the early fall.
Councillor Susan Fielding addressed the suggestion that the Arkell well may not continue to be able to meet future demand.
“To me there is a big divide between (provincial) Places to Grow legislation and the ability to supply (communities) with the amount of water they need,” she said.
Keller said the information from the Tier 3 study would certainly be directed to the province “so there is a closer relationship to where growth should occur and where water is available.”
At the same time, Keller said “we cannot direct the province to do this, we can only recommend it.”
Fielding was also interested in seeing information on the cumulative effect of non-municipal water taking.
“Being located so closely to Nestlé, we hear a lot about it,” she said. “It is very controversial. It is good to remind people that it is only a small part of the picture.”
She said to those who wish Nestlé did not exist at all, “it’s not really going to have a big impact on the water taking issues we have.”
Councillor Ken Roth asked what constitutes drought conditions in the watershed.
Keller said there are very specific conditions and guidelines.
“What we use is information on the worst historic drought in the local region which was in the early 1960s,” he said.
The climate information of that decade is entered into the computer model to look at the impact of future demands.
“So there is no science that this will happen again because of climate change?” Roth asked.
“If it hasn’t happened since 1960 …”
Keller said the assumption is that because it happened before, it can happen again.
“With climate change, we understand extremes are getting more extreme … so maybe the droughts could get even worse,” he said. “It is hard to predict, but as a worst-case scenario using some point in the past makes sense.”
Councillor Matthew Bulmer said the risk to the Queensdale and Arkell wells, “is a combination of future growth and drought conditions.”
He added that while drought is something that cannot be controlled, growth over recharge areas can be controlled.
When Guelph’s growth was identified as a risk, Bulmer asked why the report did not suggest that growth was not sustainable.
Keller agreed the city’s growth can be controlled, but it is the province which holds that control through the growth targets.
While broadly understood there should be a connection between growth and the ability to service that growth, it has not happened, Keller said.
Bulmer said the reduction of recharge areas due to growth is something the city could control.
Keller agreed it makes sense.
“It is not just about the recharge, but for surface water control and a lot of other benefits,” Keller said.
Council was told that both Guelph and Wellington County will need to draft policies to address reduced recharge areas.
Bulmer said he’s concerned with the “prioritization of use” being proposed.
“It’s telling me that residential and industrial high-use on municipal water systems should have more priority than low-use residential and agriculture-use not on municipal water systems.”
To him, it suggests not all residents are equal.
He wondered if the prioritzation should be for human and agricultural use over industrial use.
Mayor Dennis Lever echoed Bulmer’s sentiment.
“I am really concerned about the priority of use,” he said noting that the majority of water for Guelph is coming from Puslinch.
“If we give priority to that municipality’s water taking, we are taking it away from people who live where the water is,” he said.
Lever agreed prioritization may apply in some situations, but he did not believe it applied in Puslinch.
