В Стратфорде тестируют инновационные буи для очистки воды в озере Виктория

Water quality on trial as city looks to clean up Lake Victoria Article content A pair of yellow buoys designed to improve water quality are being tested in Lake Victoria for roughly nine weeks. The City of Stratford’s community services department said the innovative devices — known as equilibrium modulating fluids (EMF) devices — were placed in the water this week, with one near Tom Patterson Island and another close to the Waterloo Street bridge. Recommended Videos The trial will last until the end of October, at which time the department will gather data and decide its next steps. WHY ARE THEY NECESSARY? Runoff from organic matter and other waste, like manure and fertilizer, often finds its way from area farms and downstream into the river where it settles, said Quin Malott, Stratford’s parks, forestry and cemetery manager. Without a stream to keep it flowing quickly, the sediment sticks around and, especially during dry periods in the summer, starts to smell, which becomes an issue in a busy area of the city. WHERE DID THE DEVICES COME FROM? They were provided for free on a trial basis by EM Fluids, whose head office is in Ottawa. The company said its buoys have been deployed in more than 80 projects around the world. HOW DO THEY WORK? Designed to address lake water quality issues such as high nutrient input, algal blooms, high pH and nightly hypoxia, the devices emit a subtle power signal that changes the water’s surface properties by doubling the gas transfer rate and triggering a cascading effect that spreads throughout the waterbody to up to 19 hectares, a Canadian study of the product said. One device can double the oxygen exchange rate at the surface, which is important since organic matter and agricultural runoff create a high oxygen demand. A lack of oxygen can lead to the accumulation of sludge and smells. “We thought we might be a perfect setup for something like this if it can help clean up the waterway in the middle of the park,” Malott said. WHAT IS THE WATER QUALITY IN LAKE VICTORIA? Coliform bacteria levels are tested several times a year in different areas of the lake, and Malott said historical data has been very consistent, though he didn’t immediately have those numbers. Levels of bacteria also fluctuate depending on conditions, Malott added, especially after heavy rain. But don’t put on a bathing suit and jump into the river just yet. “We would be much higher than what is recommended for swimming conditions,” he said. WHAT’S NEXT? Once the trial is over, data will be presented to the community services department, which will look at the numbers and visual observations. “If we’re seeing results that are very obvious, it’s something we would have to take to council and see if we want to move forward with,” Malott said. Field testing already conducted in sewage lagoons, aquafarms and ponds in Israel, Thailand, China, Brazil and Canada showed that the EMF treatment alleviated oxygen stress in water bodies, said the study, which was done by two scientists with EM Fluids and two chemistry and biology professors at Toronto Metropolitan University. No extra devices would likely be needed if the city paid for them in future years, Malott said “It’s something that’s positive for the community, and if it doesn’t (work) we’re not losing anything,” he said. “If something like this does work, it could be a very positive addition to what we’ve got.”