IV. What are the effects of water pollution?

IV.1. On human health

To put it bluntly: water pollution kills. In fact, it caused 1.8 million deaths in 2015, according to a study published in The Lancet. Contaminated water can also make you sick. Every year, unsafe water sickens around 1 billion people. And low-income communities are at disproportionate risk because their homes are often closest to the most polluting industries. Waterborne pathogens, in the form of disease-causing bacteria and viruses from human and animal waste, are a major cause of illness from contaminated drinking water. Diseases spread by unsafe water include cholera, giardia and typhoid. Even in wealthy countries, accidental or illegal discharges from wastewater treatment facilities, as well as runoff from farms and urban areas, contribute to harmful pathogens in waterways. Thousands of people across the United States are affected each year by Legionnaires' disease (a serious form of pneumonia contracted from water sources like cooling towers and running water), with cases appearing from Disneyland in California on the Upper East Side of Manhattan.

Figure 3: A woman using bottled water to wash her three-week-old son at their home in Flint, Michigan

IV.2. On the environment

To thrive, healthy ecosystems depend on a complex network of animals, plants, bacteria and fungi, all of which interact, directly or indirectly, with each other. Damage to any one of these organisms can create a chain effect, putting entire aquatic environments at risk. When water pollution causes algae blooms in a lake or marine environment, the bloom of newly introduced nutrients stimulates the growth of plants and algae, which reduces oxygen levels in the water. This lack of oxygen, called eutrophication, suffocates plants and animals and can create “dead zones,” where waters are essentially devoid of life. In some cases, these harmful algal blooms can also produce neurotoxins that affect wildlife, from whales to sea turtles. Chemicals and heavy metals from industrial and municipal wastewater also contaminate waterways. These contaminants are toxic to aquatic life – most often reducing an organism's lifespan and ability to reproduce – and move up the food chain as predators eat their prey. This is how tuna and other large fish accumulate large amounts of toxins, such as mercury.

Marine ecosystems are also threatened by marine debris, which can strangle, suffocate and starve animals. Much of this solid debris, such as plastic bags and soda cans, is washed into sewers and storm drains, then eventually washed into the sea, turning our oceans into a soup of trash and sometimes consolidating to form floating garbage patches. Abandoned fishing gear and other types of debris are responsible for damage to more than 200 different species of marine life. Meanwhile, ocean acidification makes it harder for shellfish and corals to survive. Although they absorb about a quarter of the carbon pollution created each year by burning fossil fuels, the oceans are becoming increasingly acidic. This process makes it more difficult for shellfish and other species to build shells and can impact the nervous systems of sharks, clownfish and other marine life.

IV.3. What can we do to prevent water pollution?

There is no single or simple answer to stop the water pollution crisis, however, there are many solutions to prevent water pollution both in our daily lives and within industries. 

We can separate the issue with water pollution into 10 notable solutions:

• Wastewater Treatment
•  Reducing Plastic Waste 
• Water Conservation
• Water-efficient Toilets 
• Septic Tanks
• Do Not Use the Toilet as a Trash Bin
• Stormwater Management
• Green Agriculture & Wetlands
• Denitrification
• Ozone Wastewater Treatment
• Wastewater Treatment

Treating water before it enters the waterway system is probably the most efficient way of reducing water pollution – hitting the issue right at the source! 

Wastewater treatment facilities have the technology and tools to remove most pollutants through biological, physical, and chemical processes. For example, sewage treatments allow water to travel through different sanitization chambers to reduce toxic levels of water pollutants and prevent leakages into water systems. 

To ensure that wastewater treatments function properly, regular maintenance of equipment is required. This includes applications such as water treatment sensors, which are vital to measure and remove contaminants to reduce water pollution.