Managing sediment-associated phosphorus to prevent cyanobacterial blooms in drinking water reservoirs

Join forWater Network member, Nik Knezic, as he explores the dynamic topic of sediment-associated phosphorus on
Tuesday September 21 at 12pm EST.
​Contact Elanor for access.

Webinar Details
To ensure the uninterrupted supply of adequate amounts of drinking water, many utilities rely on reservoirs for raw (i.e., untreated) water storage prior to treatment. Reservoirs are not typically managed for influxes of fine sediment and associated nutrients, which are more frequent in many areas because of climate change-exacerbated landscape disturbances such as wildfires and extreme precipitation.

​Fine sediment is the primary vector of phosphorus transport in aquatic systems, which notably is the limiting nutrient for primary productivity in freshwater. Algae, especially cyanobacteria, blooms are one of the biggest threats to water quality and the provision of safe drinking water globally. Here, a series of lab- and field-scale analyses were conducted to (i) describe phosphorus release from fine sediment in a raw water reservoir, (ii) characterize its availability for biological uptake, (iii) evaluate phosphorus inactivation by application of common coagulants (FeCl3, alum, PACl), and (iv) evaluate the combination of strategically-timed reservoir dredging and coagulant application on phosphorus inactivation and turbidity reduction.

Nik's bio
Nik joined the WaterSTP group in January 2019 under the supervision of Dr. Monica Emelko after spending two years working in the water chemistry field with General Electric’s Water division. He had previously completed a BASc in the Department of Chemical Engineering at the University of Waterloo in 2017. In August 2021 he received his MASc in Civil Engineering. Nik’s current doctoral research focuses on investigating climate change adaptation strategies for protecting source water reservoir quality.

The Environmental Virology and Ecology Research Group (i.e., ENVERG; https://uwaterloo.ca/environmental-virology-ecology-research-group/) led by Dr. Nissimov is recruiting a domestic or international PhD student to investigate the interactions between harmful algal bloom-forming species and their viruses.

Project Scope: Aquatic viruses are now viewed as major drivers of biogeochemical cycles and as crucial components that shape microbial food webs. Our main understanding of these viruses derives predominantly from their study in marine habitats. To that end, it is widely accepted that they can control the abundance of dominant microbial communities, decide the faith of algal blooms, and affect the diversity of microorganisms in coastal and oceanic environments. Nevertheless, despite the ecological and societal importance of freshwater environments, our understanding of the role of viruses in freshwater habitats is at its infancy. The PhD student will work in a collaborative and cross-disciplinary environment to identify and isolate from Canadian lakes novel microalgal/cyanobacterial hosts and their viruses, investigate their diversity and co-occurrence in situ, and conduct infection-dynamics experiments in the laboratory. Collectively, these will begin to unravel the ecological significance of virus infection of harmful algal blooms in lakes.

For application details, download the PDF.

As part of Singapore’s International Water Week 2021, Water Institute member Monica Emelko, Canada Research Chair in Water Science, Technology and Policy at the University of Waterloo, was invited to share her expertise at one of the Thematic Webinars focused on climate change, water quality and health. In her talk entitled “Source Water Protection and Climate Change Adaptation for Treatment Resilience”, Emelko explored how climate change poses an array of uncertainties to the provision of adequate amounts of safe drinking water that, if not addressed, could ultimately lead to negative public health impacts. Adaptation case studies were introduced, drawing from her work evaluating trade-offs between grey (i.e., engineered) and green (i.e., natural) infrastructure. 
Monica noted that supply diversification in rural, remote, and marginalized communities is often not feasible because alternate supplies might not always be available or cost-effective. In contrast, landscape management-based approaches can deliver a myriad of larger watershed scale co-benefits that include reduced drinking water treatment costs and cost-sharing opportunities and ecosystem diversity and other socio-cultural benefits (e.g., spiritual value, recreation). These approaches can be especially relevant for rural, remote, and marginalized communities including many Canadian communities reliant on forested watersheds for water.

Original article: ​https://capitalcurrent.ca/we-need-to-learn-to-live-with-fire-say-experts-as-ontario-faces-its-busiest-forest-fire-season-yet/

‘We need to learn to live with fire,’ say experts, as Ontario faces its busiest forest fire season yet
By Clare Duncan,   2  4 min read

Forest fire smoke from Northwest Ontario moved into the rest of the province this past week, resulting in hazy conditions and poor air quality and it’s likely to become the new normal.

​Experts say we must learn to live with wildfires and adjust our existing infrastructure to mitigate the impact on communities.

There have been 968 forest fires so far this year, nearly double the 10-year average of 520, according to the Ontario forest fire information page. There are 154 active wildfires in Ontario, most in the northwest.

The Ontario Ministry of Northern Development, Mines, Natural Resources and Forestry attributes the fires to unusually hot and dry weather conditions, not seen in close to 50 years in the region.

​“Since weather conditions closely dictate fire behaviour, this dry season, as well as lightning events with minimal rainfall, is a significant factor for the high number of fires we’ve seen across northern Ontario,” says Shayne McCool, information officer for Aviation, Forest Fire and Emergency Services (AFFES), in an email statement.

Environment Canada has issued a series of air quality statements recently because of smoke moving into parts of the province from the northwest.

According to Environment Canada, “wildfire smoke is a constantly-changing mixture of particles and gases which includes many chemicals that can be harmful to your health.”

They encourage people to take extra precautions to reduce exposure to smoke, such as avoiding strenuous outdoor activities.

Not only do wildfires affect air quality, but they also have the potential to affect water quality and the amount of treatment it needs.

Historically, large wildfires in Canada have occurred mostly on more remote forested landscape, says Monica Emelko, professor of civil and environmental engineering at the University of Waterloo and drinking water treatment engineer. More recently, we are experiencing fires in urban environments.

“There are all sorts of concerns now around wildfires occurring in communities and on top of communities where there’s a lot of built infrastructure,” she says.

When the built environment burns, the by-products of manufactured materials have the potential to run into our water supply, in addition to the sediments, nutrients, and organic carbon from the natural landscape.

“Most utilities are not equipped to treat those materials. It doesn’t mean that we can’t treat them. It means that we’re not typically accustomed to looking for them in drinking water supplies, and so therefore we may not have invested in the infrastructure to treat something that hasn’t historically been present in our water supply,” says Emelko.

“The more [water quality] deteriorates, the more we have to pay to clean it.”

To properly respond to the impacts of wildfires on our communities, it’s important to integrate landscape management, says Emelko.

​“We as Canadians, in the global north, we need to realize that we are at the forefront of these impacts of changing climate, so we have to make adjustments. And it’s just the start in Ontario,” says Emelko.

One of the strategies to prevent harmful impacts of wildfires is using “fuel management” says Francois-Nicolas Robinne, research scientist for the Canadian Forest Service at the Great Lakes Forestry Centre.

This involves cutting excessive fuel and encouraging prescribed burns. Forest management teams would use fire as a tool to naturally burn the area to prevent larger, uncontrollable burns. Reducing the amount of fuel keeps our forests from burning uncontrollably and helps the natural ecological process of the forest.

“In Canada, [fire] is definitely a huge part of our forest ecosystems. What I mean by that is that our forests need to burn on a regular basis to stay healthy,” says Robinne.
The Ministry of Northern Development, Mines, Natural Resources and Forestry has imposed a restricted fire zone for most of the northwest fire region to reduce the amount of human caused fires.

The goal, they stated, is to find fires when they’re small and easier to manage and respond to fires closest to communities and infrastructure.
Ontario is receiving firefighting support from Mexico, Australia, Alberta, Québec and the Atlantic provinces.  

​“We need to learn to live with fire. Fires are going to keep burning and they are going to keep impacting our communities, including our water supply … that’s something we need to accept,” says Robinne.