The production of lettuce at the Whole Leaf greenhouse near Coaldale, Alta. is a calculated Nutrient Film Technique (NFT) that is mostly automated and efficient, not only for harvesting but also for how it uses water to grow lettuce.
“It’s a recirculating system, so we water the plants, it goes back, gets cleaned up and then it’s continually being recirculated,” said Lisa Tymensen, assistant grower and water researcher with Whole Leaf.
The 11-acre facility produces around 18 million heads of lettuce per year including supplying Wendy’s, Inspired Greens, and retailers.
As the water specialist, Tymensen monitors their metered system to know where all the water is being used and how to continually reduce their water footprint.
“The system is very efficient and we’re able to collect evapotranspiration from the plants, this is how they breathe,” said Tymensen. “Also, water gets collected from snowmelt and rain off the roof and.”
Tymensen explained they use the same amount of water in one year that an irrigation pivoter uses in five days.
Whole Leaf’s water supply comes from the St. Mary Reservoir, and when the valve opens in May, “This is when we have the opportunity to fill our storage ponds then that will last us through the summer until October, when they usually shut it off,” said Tymensen.
But this year, if there isn’t enough precipitation or snowpack, southern Alberta could be entering a third year of drought and potentially an emergency-level water shortage.
Esteban Villanueva, director of growing and operations with Whole Leaf, said a worst-case scenario could mean running out of water and being forced to stop operation.
“If we don’t have water in any given time and no visible option to bring water, we’d need to shut down,” said Villaneuva.
“We are at stage four of five levels of a provincial water emergency. The next step is to declare a province-wide state emergency,” said Trevor Lewington, CEO of Economic Development Lethbridge.
“This is pretty significant, people need to be paying attention,” said Lewington.
Lewington explains if the province were to declare a stage five emergency, the government would be able to reallocate water, primarily to supply drinking water, and secondly, to make sure producers can keep growing.
“It’s really important that we’re able to supply those companies to keep them producing to keep their employees going, and at the same time that they do their part to mitigate some of the risks that we have going into the summer,” said Lewington.
According to Villaneuva and Tymensen, a shutdown would affect not only the jobs of their 120 employees, but it would take months to prepare and get back up and running, including around 40 days to harvest the first crop of lettuce.
They’re currently working with their managers to see what options they would have if an emergency water shortage was declared.
According to Lewington, “I don’t think there is any risk of anyone shutting down, but certainly, people are going to have to be thinking smarter about how they use their water.”
Lewington explained that efficient water-use systems like Whole Leaf are what producers are continually developing to find ways to conserve water.
“In the last month we’ve been really lucky to have some good snowfall, so we’ve collected almost an Olympic-sized pool full of water, so that’s able to meet most of our irrigation needs for the winter,” said Tymensen.
Whole Leaf opened operations near Coaldale, Alta., in 2017. The main southern Alberta advantages for them were the long sunny days and access to clean water coming from St. Mary’s Reservoir.