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Today's Paper | November 23, 2024

Published 28 Aug, 2021 06:48am

Worst water calamities

Since the past several decades, the development in technology and industrialisation has changed the face of earth. But modernisation and advancement have also been at a price that we are only now beginning to realise. We now have to face and live with the fruits of mayhem that were sowed in the past several decades, putting not only our lives at stake but also that of other creatures and forms of life on land, in the air and in the oceans.

Following are some of the worst disasters that took place in the water bodies of our beautiful earth. We will see the reason behind the disaster and its effects on the living things in that area. Although there are dozens of mishaps that occurred in the oceans and rivers around the world, we have selected a few far too notorious for their nature.

So the more you learn about water contamination issues, the better you’ll understand the potential problems that might arise from contamination situations.

Gulf War oil spill (1991)

Nature: Man-made (Deliberate)

Spillage: Crude oil

Most man-made disasters are unintentional and happen as a result of an accident or malfunction. however, this was not the case in the Gulf oil spill. This disaster is considered to be among the worst and one of the biggest disasters in history. What made it happen?

In January 1991, Iraqi forces were ordered to deliberately release more than 240 million gallons of crude oil directly by opening the valves of oil tankers into the Persian Gulf in an attempt to slow down or stop the onslaught of the US troops from landing on the Gulf coast. The resulting oil slick ravaged the area’s marine ecosystem, killing thousands of seabirds and endangering other wildlife.

To date, it remains the worst disaster of its kind. It also caused several diseases and unknown illnesses widespread among the people of the area. The oil slick that was created was 101 miles long by 42 miles wide, creating a total of 4,242 square miles of oil. In some places, the slick was five inches thick.

The spill is the largest recorded oil spill in history as well as one of the largest acts of ecoterrorism ever committed. And because of the Gulf War and its aftermath, it was not cleaned up in a timely manner and hundreds of millions of barrels of oil soaked into the Earth between January and November of 1991.

Lanzhou, China, 2014

Nature: Accidental

Spillage: Benzene

Benzene is often used in the production of plastic. It is notorious for its cancer-inducing properties so when this chemical is breathed, ingested or contacted by humans for an extended period of time, it can cause cancer and damage the hematopoietic system, which produces blood.

How did it happen?

In April 2014, people of Lanzhou, the capital of North-Western Gansu province of China, were instructed not to drink water from the tap for at least for 24 hours.

Lanzhou Veoilia Water Co., the company’s plant, which distributed tap water to its three million residents, was surrounded by chemical plants (owned by a subsidiary of China National Petroleum Corporation) and had its water pipelines near the chemical pipelines. On examination, it was found out that there was a leak from a chemical pipeline underground, which contaminated tap water, containing up to 200 micrograms per litre of the toxic chemical benzene — 20 times the national safety limit.

It is believed that this led to 34 tonnes of benzene being absorbed into the groundwater in the area. Though the pipeline was repaired, the damage was still great. The authorities have since said the contamination has returned to safe levels in most areas.

Exxon Valdez, March 1989

Nature: Accidental

Spillage Crude oil

An oil tanker ship called Exxon Valdez accidentally struck the Bligh Island Reef off Prince William Sound, Alaska, and wrecked, spilling oil into the surrounding ocean. The tanker spilled 750,000 barrels of crude into Alaskan waters.

How did it happen?

On investigating the cause, it was found that lack of sleep and an overworked crew were major factors in the incident. Up to 28 million gallons of crude oil spilled over the course of a few days. The nature of the incident was purely accidental, but it could have been avoided if the ship’s collision avoidance radar was maintained and the crew had been alert.

The crude oil spilled from the Exxon in to the ocean resulting in many groups of animals seriously affected, and some pods of orca whales never recovered.

The clean-up ended up causing more harm than good when in an attempt to remove oil that had collected on the shoreline resulted in the removal of microbes that were breaking down the oil. The scientific community has since come to understand the important role these microbes play during oil disasters and have learned to work with them.

Some research and studies done in 2015, determine that oil is still present in the ocean. The environment is still suffering from this spill.

Deepwater Horizon oil spill, April 2010

Nature: Accidental

Spillage: Crude oil

The oil spill in this unfortunate event is also considered the worst accidental marine oil disaster in the history of the petroleum industry. The disaster started when the Deepwater Horizon semi-submersible mobile offshore drilling unit used by BP (British Petroleum) off the Louisiana coast, began drilling for crude oil at roughly 5000 feet into the bed of the Macondo Prospect. The gas emitted from the well was highly pressurised and shot up the drill column, causing the oil platform to explode, killing 11 workers and injuring 17 on the spot.

However, the erupting well was spewing 5000 barrels of oil a day into the ocean. After the initial explosion in April, the daily crude oil emissions continued to rise, reaching a peak of 62,000 barrels in June. By the time the well was sealed, around five million barrels of oil was spilled into the ocean.

How did it happen?

The spill was caused by methane gas entering the oil rig, this resulted in an explosion. It’s widely believed that the explosion could have easily been prevented through stricter regulations. It was also found out that the cement used during the drilling process was not thick enough, the valves failed, and the gas alarm on the rig was not in operation at the time of the explosion.

Effects

The spill has had a terrible effect on the environment. Coral, fish, dolphins and birds that called the Gulf of Mexico home have seen dwindling numbers ever since.

What is the status today?

The environment continues to suffer and the oil has not been cleaned up. Environmental protection groups are unsure if the oil will ever be completely removed from the Gulf. The incident has led to a famous Hollywood movie Deep Water Horizon, which shows exactly how things occurred on the rig.

Cyanide spill, 2001

Ghana, West Africa

Nature: Manmade

Spillage: Cyanide

In the western part of Ghana, people were exposed to water contaminated with cyanide following a terrible spill from a nearby gold mine.

The water used in the mining process is usually exposed to various toxic materials and is very hazardous to all the living organisms on earth. This is why it is strictly required to safely dispose of waste materials. Similarly, the wastewater used in the mining process in this incident was also heavily laced with cyanide as well as other heavy metals.

How did it happen?

A dam used to hold back tailings (mining wastewater) was not installed correctly in the mine, causing it to become dislodged during a period of heavy rain. This allowed the wastewater to rush into the nearby River Asuman.

Effects on the environment:

As the water was contaminated with cyanide, the fish exposed to the water died quickly. People who drank water laced with cyanide didn’t die, but developed several diseases such as cancer, nervous system disorders and birth defects.

The aftermath of disaster:

Of course, after every disaster, people look towards the government and authorities to provide safety to them. The residents of the area and the country hoped for stricter operations policies to be enacted following the spill, sadly very little was done. The country continues to see cyanide spills from mines that aren’t well regulated.

S.S. Atlantic Empress (1979)

Nature: Accidental

Spillage: Crude oil

S.S. Atlantic Empress was a Greek oil tanker that collided with the oil tanker Aegean Captain in the Caribbean, and eventually sank, having created the fifth largest oil spill on record and the largest ship-based spill having spilled 287,000 metric tonnes of crude oil into the Caribbean Sea.

The unfortunate collision and the resulting fire claimed the lives of 26 of the Empress’s crew members and one crew member on the Captain. The remaining crew was saved from both the ships.

The next day, firefighters from the Trinidad and Tobago Coast Guard brought the fires aboard the Captain under control, and members of her crew returned to the ship, and were able to bring her into Curaçao (Dutch Caribbean island), where her cargo was off-loaded.

But even a week after the collision, the Empress was still burning, and when an explosion occurred, it increased the rate of oil flow to 26 to 57 cubic metres per hour (7,000 to 15,000 gal/h), twice the previous rate. Finally, on August 3, the Empress sank, having spilled 287,000 metric tonnes of crude oil into the Caribbean Sea.


Great Pacific/North Atlantic Garbage Patches (1985*—Present)

You may have seen pictures showing garbage floating on the surface of the ocean several times. But we are not talking about some handfuls of garbage; we are talking about tonnes and tonnes of garbage that’s floating on the surface of Atlantic and Pacific oceans — a problem that has existed for centuries.

The problem is ever increasing and becoming severe as humans began producing more non-biodegradable materials like plastics and cleaning products.

Researchers claim that cruise ships are to blame for roughly 20% of the garbage accumulated in these patches while the remaining 80% comes from land-based sources. The garbage patches are estimated to take up between .41% and 8.1% of the ocean’s surface.


Dead zone

A dead zone, in oceanic terms, means an area where water has little oxygen. Every living organism relies on oxygen and lack of oxygen makes the possibility of life impossible for most marine creatures. The deprivation of oxygen happens when there is an overabundance of nutrients in the water. Algae feed on these nutrients and begin to overgrow. When algae die, they decompose and it’s this decomposition that reduces oxygen in the water.

Apart from that, human interference like farming and other activities have tripled the nitrogen levels of the water along the coast. These continued activities further expand the Mississippi/Gulf of Mexico dead zone every year. The dead zone is now roughly 8000 square miles.

Published in Dawn, Young World, August 21st, 2021

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