Water Pollution

Water:

Water is the driving force of all nature and nothing is more flexible than water, yet nothing is able to resist.

British poet W. H. Auden once noted, “Thousands have lived without love but yet no one without water.”

While we all know water is crucial for life, we trash it anyway. 80 percent of the world’s waste is dumped largely untreated back into the environment, polluting rivers, lakes, and oceans.

What Is Water Pollution?

Water pollution is the contamination of water by any mean possible.

Water pollution occurs when harmful substances often chemicals or microorganisms contaminate a stream, river, lake, ocean, aquifer, or other body of water, degrading water quality and rendering it toxic to humans or the environment.

Major Sources of Water Pollution:

1. Point Source

2. Dispersed Source

Point Source:

When contamination originates from a single source, it’s called point source pollution. Examples include wastewater (also called effluent) discharged legally or illegally by a manufacturer, oil refinery, or wastewater treatment facility, as well as contamination from leaking septic systems, chemical and oil spills, and illegal dumping. The EPA regulates point source pollution by establishing limits on what can be discharged by a facility directly into a body of water. While point source pollution originates from a specific place, it can affect miles of waterways and ocean.

Nonpoint source:

Nonpoint source pollution is contamination derived from diffuse sources. These may include agricultural or storm water runoff or debris blown into waterways from land. Nonpoint source pollution is the leading cause of water pollution in U.S. waters, but it’s difficult to regulate, since there’s no single, identifiable culprit.

What Are the Causes of Water Pollution?

Water is uniquely vulnerable to pollution. Known as a “universal solvent,” water is able to dissolve more substances than any other liquid on earth. It’s the reason we have Kool-Aid and brilliant blue waterfalls. It’s also why water is so easily polluted. Toxic substances from farms, towns, and factories readily dissolve into and mix with it, causing water pollution.

Some of the major causes of water pollution are;

Agricultural:

Not only is the agricultural sector the biggest consumer of global freshwater resources, with farming and livestock production using about 70 percent of the earth’s surface water supplies, but it’s also a serious water polluter. Around the world, agriculture is the leading cause of water degradation. In the United States, agricultural pollution is the top source of contamination in rivers and streams, the second-biggest source in wetlands, and the third main source in lakes. It’s also a major contributor of contamination to estuaries and groundwater. Every time it rains, fertilizers, pesticides, and animal waste from farms and livestock operations wash nutrients and pathogens such bacteria and viruses into our waterways. Nutrient pollution, caused by excess nitrogen and phosphorus in water or air, is the number-one threat to water quality worldwide and can cause algal blooms, a toxic soup of blue-green algae that can be harmful to people and wildlife.

Sewage and Wastewater:

Used water is wastewater. It comes from our sinks, showers, and toilets (think sewage) and from commercial, industrial, and agricultural activities (think metals, solvents, and toxic sludge). The term also includes storm water runoff, which occurs when rainfall carries road salts, oil, grease, chemicals, and debris from impermeable surfaces into our waterways

More than 80 percent of the world’s wastewater flows back into the environment without being treated or reused, according to the United Nations; in some least-developed countries, the figure tops 95 percent. In the United States, wastewater treatment facilities process about 34 billion gallons of wastewater per day. These facilities reduce the amount of pollutants such as pathogens, phosphorus, and nitrogen in sewage, as well as heavy metals and toxic chemicals in industrial waste, before discharging the treated waters back into waterways. That’s when all goes well. But according to EPA estimates, our nation’s aging and easily overwhelmed sewage treatment systems also release more than 850 billion gallons of untreated wastewater each year.

Radioactive Substances:

Radioactive waste is any pollution that emits radiation beyond what is naturally released by the environment. It’s generated by uranium mining, nuclear power plants, and the production and testing of military weapons, as well as by universities and hospitals that use radioactive materials for research and medicine. Radioactive waste can persist in the environment for thousands of years, making disposal a major challenge. Consider the decommissioned Hanford nuclear weapons production site in Washington, where the cleanup of 56 million gallons of radioactive waste is expected to cost more than $100 billion and last through 2060. Accidentally released or improperly disposed of contaminants threaten groundwater, surface water, and marine resources.

Oil Pollution:

Big spills may dominate headlines, but consumers account for the vast majority of oil pollution in our seas, including oil and gasoline that drips from millions of cars and trucks every day. Moreover, nearly half of the estimated 1 million tons of oil that makes its way into marine environments each year comes not from tanker spills but from land-based sources such as factories, farms, and cities. At sea, tanker spills account for about 10 percent of the oil in waters around the world, while regular operations of the shipping industry through both legal and illegal discharges contribute about one-third. Oil is also naturally released from under the ocean floor through fractures known as seeps.

What Are the Effects of Water Pollution?

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 ill. Every year, unsafe water sickens about 1 billion people. And low-income communities are disproportionately at 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 nations, accidental or illegal releases from sewage treatment facilities, as well as runoff from farms and urban areas, contribute harmful pathogens to waterways. Thousands of people across the United States are sickened every year by Legionnaires’ disease (a severe form of pneumonia contracted from water sources like cooling towers and piped water), with cases cropping up from California’s Disneyland to Manhattan’s Upper East Side.

Even swimming can pose a risk. Every year, 3.5 million Americans contract health issues such as skin rashes, pinkeye, respiratory infections, and hepatitis from sewage-laden coastal waters, according to EPA estimates.

One source estimates that each year 53,000 Pakistani children die of bacterial diarrhea from contaminated water. The main alternative is bottled water, which much of the population cannot afford. And, many of the major brands have been exposed as contaminated.

On The Environment:

In order to thrive, healthy ecosystems rely on a complex web of animals, plants, bacteria, and fungi. All of which interact, directly or indirectly, with each other. Harm to any of these organisms can create a chain effect, imperiling entire aquatic environments.

When water pollution causes an algal bloom in a lake or marine environment, the proliferation of newly introduced nutrients stimulates plant and algae growth, which in turn reduces oxygen levels in the water. This dearth of oxygen, known as eutrophication, suffocates plants and animals and can create “dead zones,” where waters are essentially devoid of life. In certain cases, these harmful algal blooms can also produce neurotoxins that affect wildlife, from whales to sea turtles.

What Can You Do to Prevent Water Pollution?

With Our Actions:

We’re all accountable to some degree for today’s water pollution problem. Fortunately, there are some simple ways you can prevent water contamination or at least limit your contribution to it;

• Learn about the unique qualities of water where you live. Where does your water come from? Is the wastewater from your home treated? Where does storm water flow to? Is your area in a drought? Start building a picture of the situation so you can discover where your actions will have the most impact—and see if your neighbors would be interested in joining in!

• Reduce your plastic consumption and reuse or recycle plastic when you can.

• Properly dispose of chemical cleaners, oils, and non-biodegradable items to keep them from going down the drain.

• Maintain your car so it doesn’t leak oil, antifreeze, or coolant.

• If you have a yard, consider landscaping that reduces runoff and avoid applying pesticides and herbicides.

• Don’t flush your old medications! Dispose of them in the trash to prevent them from entering local waterways.

• Be mindful of anything you pour into storm sewers, since that waste often won’t be treated before being released into local waterways. If you notice a storm sewer blocked by litter, clean it up to keep that trash out of the water. (You’ll also help prevent troublesome street floods in a heavy storm.)

• If you have a pup, be sure to pick up its poop.

With Your Voice:

One of the most effective ways to stand up for our waters is to speak out in support of the Clean Water Act, which has helped hold polluters accountable for five decades despite attempts by destructive industries to gut its authority. But we also need regulations that keep pace with modern-day challenges, including micro-plastics, PFAS, pharmaceuticals, and other contaminants our wastewater treatment plants weren’t built to handle, not to mention polluted water that’s dumped untreated.

Tell the federal government, the U.S. Army Corps of Engineers, and your local elected officials that you support water protections and investments in infrastructure, like wastewater treatment, lead-pipe removal programs, and storm water abating green infrastructure. Also, learn how you and those around you can get involved in the policymaking process. Our public waterways serve every one of us. We should all have a say in how they’re protected.

Role of Biotechnologist:

As a biotechnologist we can treat water by using two process;

1. Aerobic treatment

2. Anaerobic treatment

1. Aerobic treatment:

Aerobic process can be characterized into two;

a. Suspended Growth System

b. Attach Growth System

a. Suspended Growth System

It includes;

i. Activated Sludge

ii. Oxidation Ditches

iii. Oxidation Pounds

b. Attach Growth System:

It includes;

i. Tricking filters

ii. Rotating biological containers

2. Anaerobic Treatment:

• This process is carried out in specially design reactors.
• The treatment process consists of mixing of sewage with recycled solid sludge and then digestion under anaerobic conditions.
• After the digestion is complete the supernatant effluent is discharge and then settle sludge is recycled.

It is also characterized into two;

a. Attached Growth System:

i. Up flow anaerobic sludge blanket digestion.

ii. Anaerobic filter process

b. Suspended Growth System:

i. Anaerobic Contact Digestion.

ii. Septic tanks

iii. Imhoff tanks

References:

NRDC

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