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AC Atienza, Brendan Bate, Shannon Smithwick, Steff Stephansson, Kaleigh Watson, Andrew Wilson.
Water pollution is something that is sometimes obvious: think of plastic bags floating in a river or an oil slick spreading out across a lake. However, perhaps more dangerously, pollution can also be invisible: think of chemicals being released from industrial sites into rivers and streams.
There is a great deal of credible and detailed information already available on the internet and there is little point in trying to replicate that here. This article will provide an overview of water pollution and some related issues. More information is available via the references if you choose to dive deeper into the topic.
As defined by Encyclopaedia Britannica, “pollution” is defined as “the addition of any substance … energy … to the environment at a rate faster than it can be dispersed, diluted, decomposed, recycled or stored in some harmless form [1]. “Water pollution” is, obviously, more narrowly defined as the release of substances or energy into a water body at a rate that the release “interfere[s] with beneficial use of the water or with natural functioning of ecosystems” [2].
Pollution is often thought of as anthropogenic (i.e. human caused) but, technically, pollutants can also come from natural sources such as minerals leaching from the ground through which the water travels [3].
Pollution is also classified into “point source” and “non-point source”. As the terms suggest, point source pollution is used when the source is a single identifiable source such as a factory. Non-point source pollution, on the other hand, is pollution which cannot be pinned to a single source and arises from a large area such as urban run-off [4] or airborne pollutants falling from the air.
Pollutants such as heavy metals [5], chemicals , and pathogens (e.g. blue-green algae) can contaminate drinking water sources. Drinking polluted water may lead to diseases such as cholera, dysentery, and other gastrointestinal issues. A 2022 report estimates that water pollution is responsible for 1.4 million deaths annually [6]. More broadly, it is estimated that over 2.2 billion people globally do not have access to safely managed drinking water [7].
Recreational use of polluted water (e.g. swimming) can also lead to illnesses such as skin rashes, respiratory infections, and other illnesses. Advisories about blue-green algae, for example, warn people to avoid all contact with the water and note that boiling water from water polluted with blue-green algae will not remove the toxins [8].
Waterborne diseases from pollution can lead to higher healthcare costs for individuals and governments. Treating such illnesses can impose significant financial burdens on communities, especially in Lower and Middle Income Countries which often lack water treatment capacity [9] and may also offer limited access to healthcare [10].
Communities relying on fishing or tourism can suffer economically as polluted waters deplete fish stocks and deter tourists (e.g. Antigua & Barbuda [11]). Such losses can result directly from costs such as repairing pollution-caused damage to equipment or reduced earnings because tourists are deterred from visiting polluted areas. There may also be related indirect costs such as the costs of cleaning up the pollution or lost investment opportunities.
Pollutants can accumulate in and on fish and crops irrigated with polluted water, posing health risks to consumers (e.g. “blue baby syndrome” in infants from nitrates and organophosphate accumulation [12]). Further, contaminated irrigation water can lower crop yields and affect food security [13], particularly in agricultural communities.
Communities may be forced to relocate due to water pollution, especially if their water sources become unusable for consumption or growing the foodstuffs they need. For example, saltwater intrusion is believed to be driving population migration in areas of Mexico and Bangladesh [14] while there is rising concern in island nations over water supply in the face of rising sea levels [15].
Polluted water can, in effect, result in less safe-to-use water being available. The resulting scarcity can worsen social tensions and inequalities within communities. The issues can range from different parts of the community having different levels of access to safe and secure drinking water to competing priorities for the use of the water. For example, industrial and agricultural users may be competing for the same water, or people in established suburbs with functioning water distribution systems may have better and/or cheaper access to potable water than people in informal settlements reliant on, say, bottled or untreated water [16].
There is a great deal of published material on the ecological effects of water pollution. What follows is a high-level summary of some key issues.
Pollutants can be toxic to aquatic organisms, leading to reduced populations and biodiversity. Heavy metals, chemicals, and plastic debris can be particularly harmful. Pollution can degrade habitats such as coral reefs, wetlands, and mangroves, which are crucial for many species’ survival.
Excess nutrients, particularly nitrogen and phosphorus, can lead to algal blooms, which deplete oxygen in the water, causing dead zones where aquatic life cannot survive. See here for more information.
The terms refer to the accumulation of pollutants in the food chain but mean different things. “Bioaccumulation” refers to the accumulation of substances in a specific organism as it lives and feeds in the environment. “Biomagnification”, on the other hand, refers specifically to the increasing concentration of the substance in the organisms higher up the food chain as they eat organisms lower down the food chain [17]. A classic example of this is the biomagnification of DDT, an insecticide which started being used in the 1940s [18]. Several decades later, DDT was widely banned due to its toxic effects higher up the food chain.
The bioaccumulation and biomagnification of pollutants in the food chain can threaten the health of organisms in the food chain and may, ultimately, pose health threats to humans.
Pollution can alter the chemical composition of water, affecting processes such as nutrient cycling and energy flow within ecosystems or simply killing the aquatic life (e.g. a Romanian tailings pond collapse is thought to have killed 1200 tonnes of fish). These ecological effects can arise from both short-term (i.e. “acute toxicity”) or long-term (i.e. “chronic toxicity) presence of the pollutants [19]. However, lack of knowledge may make it difficult to connect the observed effects on the ecosystem to a specific pollutant.
Pollution can also degrade the quality of the aquatic ecosystem to the point that it is no longer safe to consume products such as fish (e.g. the methylmercury contamination issue in Grassy Narrows, Canada [20]) and such pollution may last for decades.
The options for dealing with pollutions can be loosely grouped into measures aimed at preventing pollution in the first place and measures intended to address pollution once it is in the water. Some measures may work to both prevent the pollution and also reduce existing contamination.
Proper recycling and proper disposal of waste will prevent litter and pollutants from entering water bodies. This can be done through programs to manage solid and hazardous waste to prevent it from entering waterways. Implementing policies to support recycling programs, promote activities such as composting, and the provision of disposal facilities for hazardous materials will all help.
Implementing sustainable farming practices such as crop rotation, reduced use of pesticides and fertilizers, and the use of organic alternatives can reduce the amount of contaminants which can be washed off the land into water bodies. Further, using “buffer strips” along waterways will help to absorb excess nutrients and reduce runoff. Helping local farmers to adopt sustainable agricultural practices can reduce soil erosion, runoff, and chemical use. Such practices include cover cropping and crop rotation.
Implementing green infrastructure measures such as rain gardens, permeable pavements, retention ponds, green roofs and vegetated swales will help capture and filter urban stormwater runoff before it enters waterways.
Effective regulations on industrial discharges can provide guidance and minimum requirements to ensure that factories and plants treat wastewater before releasing it into the environment. However, those subject to such regulations need regular monitoring to enforce compliance with the specified environmental standards.
Once the contaminants are in or on the water, the focus needs to turn to remediation. Sometimes, however, the remediation implemented is simply dilution in which the concentration of a pollutant is lowered to levels which are no longer considered to be a concern or can be addressed through natural processes (e.g. Victoria, BC, sewage treatment until 2020 [21]). This is the source of the saying “The solution to pollution is dilution”.
However, this approach does not always solve the problem. In some cases, especially in the case of non-soluble pollutants, the “dilution” may simply move the pollutant downstream which may negatively affect or cause concern among downstream users. In other cases, the “safe level” of the contaminant is unknown or a matter of disagreement. Lead, for example, in the United States is now considered to have no safe level in drinking water [22]. However, Canada permits a low level of lead in drinking water [23]. Further, as technology and science has advanced, there is a growing awareness of the potential negative effects of chemicals. These “Contaminants Of Emerging Concern” typically have not yet been sufficiently studied for a clear understanding of their effects and risk thresholds [24]. Thus, the effects of “dilution” are not well understood, and the approach may not be as effective as hoped.
Treatment plants can remove a wide range of pollutants, including chemicals, heavy metals, and pathogens. However, they require significant resources (finance, scientific knowledge, operating skills, personnel) to build, operate and maintain. Not all communities, especially smaller communities, are able to find or dedicate the necessary resources. The lack of resources is a widespread problem: on a global level, 3.4 billion people “lacked safely managed sanitation services” in 2022 [25]. Here in Canada, an estimated 219 million cubic metres of municipal wastewater was released with no treatment in 2020 [26].
Communities can work to reduce pollution by organising regular clean-up events along rivers, streams, beaches, and other water bodies to remove litter and debris and prevent them from entering the water. This type of activity also helps to raise awareness of the effects of water pollution and may encourage lower household pollution.
Restoring natural wetlands or creating new wetlands (e.g. Lost Lagoon wetland in Vancouver [27]), especially in urban areas, takes advantage of their natural filtration capabilities. Such areas also provide other ecosystem services [28] such as habitat for wildlife and green spaces which can enhance the “livability” of the urban environment for both the community and other species. Similarly, other green infrastructure such as bioswales or rain gardens can help mitigate urban pollutants [29].
As with many other human-caused issues, there are the usual social measures which can be implemented.
Public awareness campaigns can be used to educate residents about the sources and effects of water pollution and ways to prevent it. At the school level, environmental education programs can teach children about the importance of water quality and pollution prevention. Involving community members, local businesses, and other stakeholders in water management decisions and initiatives will lead to greater participation in solving problems. Similarly, encouraging citizen science projects where community members can monitor local water quality and report pollution incidents will help
Policies and regulations aimed at protecting water quality, such as limits on pollutant discharges and penalties for violations can be developed. Their effectiveness is likely to depend on how ambitious the targets are and how effectively the policies and regulations are enforced. It may be possible to provide incentives for businesses and individuals to adopt pollution-reducing practices.
Integrating water management into urban planning to ensure that new developments include sustainable water use and pollution prevention measures will also help.
As we said at the beginning, there is a lot of material available on water pollution, its causes, and its effects. Polluted water is a global problem whose importance growing because of:
While there is much pollution that is out of our individual hands, it is important that we do what we can on an individual level to reduce the pollution that we individually may cause.
We can also work with others to clean up existing pollution and support community efforts to push for stronger anti-pollution laws, regulation and enforcement.
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Ross has extensive executive experience in Operations, Governance, Information Technology and Strategy at the board and senior management level including Mancal Corporation, Mancal Energy, Highridge Exploration and Atlantis Resources. He has worked in Oil and Gas, Coal, Commercial Real Estate, Portfolio Management, Recreation, Retail and Water and Wastewater Treatment. His experience is also geographically diverse having overseen operations in Canada, the United States, United Kingdom and Northern Ireland. Additionally, he has been on the board of companies with operations in Argentina, Azerbaijan, Barbados, Kazakhstan, and Russia. He has served on numerous Public, Private and Not for Profit Boards across a number of industries.
Ross has been active on several industry Boards and committees including the Canadian Association of Petroleum Producers (CAPP) and The Schulich School of Engineering Industry Advisory Council at the Schulich School of Engineering.
Brian is a seasoned Cleantech entrepreneur with a proven history of successfully bringing complex water technologies to the market. With over 25 years of experience, he has led various organizations to achieve significant milestones in the industry.
Having started as the founding CEO of the Pressure Pipe Inspection Company (PPIC) and later taking the helm at the Water Technology Acceleration Project (WaterTAP), Brian’s entrepreneurial spirit has been instrumental in driving innovation and growth within the sector.
He is an active investor in the cleantech sector and has served on many boards including the Ontario Clean Water Agency.
Actively engaged in industry associations like AWWA, WEF, IWA, and ASCE, Brian enjoys collaborating with fellow professionals to promote advancements in the field.
Brian holds an undergraduate degree and a PhD in Physics from Queen’s University, which has provided him with a solid technical foundation. As a member of the Institute of Corporate Directors, he brings valuable insights to corporate governance.