The North Saskatchewan Watershed Alliance (NSWA) recently teamed up with environmental studies students from Kings University College in Edmonton to complete a research project designed to assist in the development of a lake management strategy for Lac St. Cyr.
“The main initiative was a water quality assessment on Lac St. Cyr, which we completed here at NSWA,” said NSWA basin planner Melissa Logan. “Then as a side project we had three students from Kings College work on doing some water quality modeling for the lake.”
Lac St. Cyr has been supplying the Town of St. Paul and surrounding area with drinking water since 1951, however low water levels prompted the construction of a diversion from the North Saskatchewan River in 1978.
Logan added that the students, Alyssa Wesselson, Jacinda Johnston and Chelsea Dyck, were tasked with building a predictive water quality model of Lac St. Cyr. Members of NSWA and Alberta Environment and Sustainable Development coached the students on how to use water sciences and skills learned in the classroom to understand the lake.
The students use a computerized water quality model developed by the U.S. Army Corps of Engineers called BATHTUB to research the evolution of Lac St. Cyr’s water quality.
“What the model does, is you input things like flow and nutrient inputs, and you can kind of predict, if there’s a change in the water level, what the water quality would look like,” Logan said of the BATHTUB model, which was run out of Edmonton. “It’s just a rough tool to assist with water quality management.”
Wesselson said that while the trio tasked with the project had some familiarity with the subject from a previous Limnology (study of freshwater ecosystems) class, using BATHTUB came with its challenges.
“We didn’t know anything about it coming into it, so it was a learning experience for us. There was a manual that we read through, and having the Limnology class we knew a bit about your basic nutrients and which ones are important for lake-water quality and how the lake functions,” Wesselson said. “Once we got all the data into the model and we saw what the levels were like we could kind of relate it back to what we remembered from Limnology for levels of healthy water quality.”
Wesselson pointed out that through the project the students discovered that the diversion has had a profound effect on the water quality at Lac St. Cyr.
“We found out that the lake is starting to resemble more of the river’s water quality because of the diversions going in,” Wesselson said, adding that she and her fellow students looked back over the decades since the diversion was put in place.
“Once the Capital Region wastewater treatment plant was started in the 1980s, it really cleaned up the water quality in the river, which was seen in the lake itself in the 1990s.”
Logan added that the diversion has played a big role in improving the water quality at Lac St. Cyr.
“Since the diversion started it has changed. So some of the ion concentrations have shifted to reflect what’s in the river and nutrient levels have actually decreased quite significantly,” she said, adding that while the water quality at the lake is impressive, sufficient monitoring is necessary.
“We’ve recommended that there be regular monitoring done on the lake because it is a drinking water source for the Town of St. Paul. So we put together some recommendations about some of the parameters that they should be monitoring and frequency and maybe some wildlife studies that should be updated.”
