While the riparian area surrounding the Chain Lakes is healthy and pike numbers are flourishing, the water quality of the lakes is poor.
A Friends of the Chain Lakes water health discussion was held at Scott School Community Centre on Wednesday, April 29, when three speakers, one each for the riparian, water and fish studies made presentations.
Cows and Fish riparian specialist Kerri O’Shaughnessy told the participants that Friends of the Chain Lakes had partnered with Cows and Fish in 2014 for a Project Area Riparian Health Inventory. In July and August of 2014, seven sites were chosen for study.
Of those sites, some were in Ponoka County and some in the County of Lacombe. Two were along the Upper Lake, one sat on the banks of the Lower Lake and four were along Parlby Creek.
O’Shaughnessy says one of the most unique aspects of the Chain Lakes is the high, steep banks of the valley the lakes are situated in. This leaves little area for the green fringe of the riparian area that sits between the water and the banks. The riparian area varied from 1 meter to 200 meters wide, with an average of 10 meters.
However, the banks hold heavy amounts of vegetation, which aids the riparian area as a whole because of the buffer it provides.
“Healthy riparian areas provide a whole bunch of things to us as a society,” said O’Shaughnessy. She listed clean water, abundant water, good soil, hunting and fishing as a few examples.
Of the seven riparian sites, six (86 per cent) scored healthy. One (14 per cent) scored healthy but with problems. The average riparian site score of the project was a healthy 85 per cent. “Compared to the provincial average, which is 69 per cent . . . the seven sites averaged out 85 per cent,” said O’Shaughnessy.
“According to our category, it’s functioning properly,” she added.
The scoring of the sites is based on a visual, categorical scoring system. “It’s a combination of things that make up a healthy riparian area,” said O’Shaughnessy.
Along the banks of the valley, within the seven sites, 167 different species of plants live. O’Shaughnessy says 81 per cent are native species, approximately 4 per cent are invasive. “All sites had at least one invasive plant species on them.”
She added, 76 per cent of the project area is trees and shrubs. “And there’s lots of young plants.”
Browsing and utilization of plants is in a healthy but with problems state. The removal of non-browsing plants is healthy. Six per cent of the project area has alterations to the plant community by human causes.
Approximately 1 per cent of the project area is bare soil, which is a healthy number.
The number of streambank and floodplains alterations are healthy but the severity of the alterations are unhealthy. “There is a small number of sites (that) skewers the results,” said O’Shaughnessy.
“So what has been achieved with all this? Hopefully we’ve increased awareness,” said O’Shaughnessy.
“And you’ve also created an ability to monitor progress,” she added.
In 2001 and 2014, the Alberta Lakes Water Management Society analyzed the water of the Lower Chain Lake. In 2001 and 2013, the middle lake was tested and in 2011 the upper lake was looked at.
Friends of the Chain Lakes member Pat McMillan explained the variables measured through the analyses that are sensitive to human contact and will affect the quality of the water.
One of the aspects of the lakes noticed was they have almost no thermal stratifications; the water is the same temperature throughout the depth of the lakes. The lakes sit between a 21.4 and a 23. 2 max temperature, which he noted is fairly high.
McMillan says higher temperatures promote bacteria and stress fish while cooler pockets are needed for the health of fish.
The water density of the lakes is also not good. “It measures how far light will travel through the water for photosynthesis. And we need that,” said McMillan.
Light only travels into the water approximately 2 meters; mostly because the lakes do not clear of silt on the average schedule most do. The depths of the lakes measure between 20 and 30 feet.
The amount of dissolved oxygen in the lakes is at an unhealthy state. “All had very poor water concentrations and it went down the entire depth,” said McMillan.
He says the lakes are iced over for approximately six months of the year, six months with no new oxygen reaching the lakes. “Overall we come out very pro-oxygenation.”
In 2014 the lower lake scored a 112 for phosphorous, in 2013 the middle lake had a 260 and in 2011 the upper lake was at 345. “The upper lake is almost three times higher than the lower lake,” said McMillan.
“Phosphorous is normally in very short supply for lakes,” he added. Even a slight increase can promote unhealthy algae blooms.
Once phosphorous is in a lake is stays, recycling through the water depths and silt, says McMillan.
In summary, McMillan says the Chain Lakes are high in nutrients, high algae concentrations, low dissolved oxygen, no heavy metals, and extremely poor water quality. The lower lake in the best state and the Upper Chain Lake the worst.
Jason Cooper, fisheries biologist with the Government of Alberta Sustainable Resource Development, prairie areas, spoke during the presentations evening. “We conducted the work in September.”
“Basically it set a new record in Alberta,” he added. Using a netting system, an average of 38.7 pike per net were caught in the lower lake between Sept. 16 and 19. Cooper says the provincial average is seven per net.
In the Lower Chain Lake seven age groups were represented in the fish caught. They averaged between 400 and 600 millimeters, with a few over 700 millimeters.
“We find fish are maturing by age one,” said Cooper. The number is a bit earlier than the provincial average.
In the middle lake, surveyed at the same time, pike averaged 11. 8 per net. They were predominately one-year-old fish. Cooper says this might be a result of the lower water quality of the middle lake.
Also, the fish feed mainly on fresh water shrimp, Copper says fish that do not feed on other fish generally have smaller growth rates.
The Upper Chain Lake was not properly surveyed. “We didn’t have time for that,” said Cooper.
Two nets were placed in the lake and a maximum of seven fish were caught, not enough to make any determinations.
Participants questioned how the fish numbers were so high when dissolved oxygen levels in the lakes are poor. “We do know that pike can live in two milligrams per liter,” said Cooper.
Friends of the Chain Lake chairperson Joanne McMillan says the next steps are to continue with education and public awareness, to make the actions of people in the area health contentious for the lakes. The group is also considering a point investigation for water pollution in Upper Chain Lake. “Because the upper lake is so high we feel there’s a source. If we can find it, we can deal with it.”