NEW ALGAE DETECTION TECH BEING USED ON LAKE ERIE
This story is brought to you in part by Nature's Pond
By Ronan O'Doherty
With the three year anniversary of Toledo, Ohio's algae related water crisis in the rear-view, scientists are making headway on providing accurate monitoring tools to ensure a similar occurrence doesn't happen again.
In August of 2014 a particularly large bloom of blue-green algae, also known as cyanobacteria found its way into the city's water supply system, prompting a do-not-consume advisory for its 400,000 residents. Blue-green algae can produce a toxin called microcystin, which can wreak havoc on the livers and nervous systems of those that consume and/or engage in water activities like swimming around it.
It is generally caused by an excess of nutrients, most notably phosphorous, which the bacteria thrive on, entering a water system from sources like agricultural run-off and septic systems.
With Lake Erie being the shallowest of the Great Lakes, it is the most susceptible to these large blooms.
Tom Johengen is a research scientist with the Cooperative Institute for Great Lakes Research at University of Michigan. He dates his involvement with these programs back to 2006 when he began work on one called |Oceans and Human Health which had two focus': Beach Health and Harmful Algae Blooms (HABs).
According to Johengen that specific program lasted about three years but once they got into the monitoring and research of HABs, they picked it up as an internal program at the National Ocean and Atmospheric Administration (NOAA) with a lot of its support coming from Great Lakes Restoration Initiative Funding.
"We have weekly monitoring programs, real time buoy systems and the ecological forecast, which is achieved using satellites," said Johengen.
Just recently, they've added a new component to their monitoring that looks to improve the results they collect as well as the efficiency in collecting them significantly.
"Typically what we had being doing was once-a-week ship based sampling with eight stations across Lake Erie," said Johengen, "We'd analyze it and report it out to other scientists weekly."
Three years ago the program was able to acquire an environmental sample processor (ESP) and have since been working on it to suit their specific monitoring needs.
"It took a couple years to develop the specific assay to detect the mycrocystin and we had to develop a specific assay for it to work in fresh water," he said, "This is the first year in which we expect it to deliver data on a regular basis."
The new portable robotic lab can deliver data to the scientists every four to six hours but Johengen says they're typically doing one or two a day and can generate results over four hours.
"It can give more advanced warning that once a week," he went on to say, "The main thrust was to make in situ measurements consistently at a much higher time resolution, so we can provide better warnings."
There are some limitations to the technology at this phase however. As the unit is quite expensive, coming in at around $375,000, the program only has one of them, so can they are limited to using it in one spot on the lake at the moment.
"They are expensive in terms of purchasing and man power to run them but we were fortunate to get additional funding to purchase two additional ESPs in the next year," Johengen said, "Hopefully in the next couple years we'll have a few of them across the lake and ultimately tie that toxicity data to our models so we can predict where those toxin levels are likely to be moving in the lake."
Johengen referenced the 2014 Toledo water intake crisis when talking about why the research and technology are so important today.
"We will try to ensure that never happens again, both the economic and health impact were too much. Water treatment has the ability to remove this toxin from the water but they need to know what's coming their way," he said, "And our ability to give them a heads up once a day is a significant improvement than what we were doing while collecting samples with ships."
One other advantage of this type of technology is it will improve our understanding of how algal blooms are responding to management strategies. A new target phosphorous load has been set by an international joint commissioned study.
They believe that the severity and size of HABs can be greatly reduced if there is a 40% reduction in phosphorous.
"By being able to closely measure the bloom levels and toxicity levels," Johnegen said, “we'll have a better idea of whether those bloom are responding to reduced nutrient loads. It might take years for those reductions to meet their targets but it'll give us an improved understanding."
Richard Stumpf, Ph.D is an oceanographer with NOAA. His team has been monitoring algal blooms in the Great Lakes as well but from a little further away than Johengen's team does.
They utilize satellite technology to track the size and positioning of the blooms and then share information with the lake level teams for a more detailed data picture.
"There have been satellites that measure ocean colour going back a number of years," Stumpf said, "An experimental satellite went up in 1978 which they were using on ocean systems to compare shades of blue. What changed this was a satellite using a sensor called MERIS (Medium Resolution Imaging Spectrometer), where instead of measuring blue green and red lights it measured multiple wavelengths as well as infrared light. Those made it possible to detect blooms in turbid water. We worked through and came up with a method and found we were reliably finding blue-green algae in Lake Erie."
Stumpf said that they started using the MERIS regularly in 2008 but it took a few years before the data was available in real time. Once it was, his team developed a routine monitoring system for Lake Erie, the results of which are published in bulletins that can be signed up for on NOAAs website. They currently have about 2000 subscribers at the moment, 200 of which are located in Canada.
The work the team is doing is a boon to those running public water systems along Lake Erie.
"The public water suppliers are served well as they have to do more to treat the water when there's a bloom," Stumpf said.
That can cost a lot of money especially when they're guessing at the severity of the bloom and whether or not it's even close enough to their intake to occasion the use of the extra treatment.
"If we can say where it is and how much is going to the bottom, they're in a better place to ensure it doesn't happen again," he said, "Right now, we're addressing the practical and managing the impact so people can use the lakes and water plant operators can treat the water in the most effective way."
Stumpf echoed Johengen's thoughts on where the technology can help prevent blooms in the long run.
"Another part in this is prevention, which involves reducing phosphorous loads into the lake," he said, "We have 15 years of data on the intensity of blooms in Lake Erie, so the people dealing with agricultural run-off can see the key factors like when it's coming and where it's originating from and then address it. If we can reduce phosphorous by 40% then we can see substantially reduced blooms and in some years almost no bloom at all."
If the technology can help a city of 400,000 or a hamlet of 15,000 reduce the risk of water poisoning, while providing info that could help end the blooms altogether, it will be well worth it.
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