Every single activity that we do, whether it is households, industrial, or agricultural activity produces wastewater. The wastewater we produce from our activities contains so many pollutants, whether it is organic or inorganic.
In most case, the wastewater we produce will be transferred to one aquatic system and then mixed with feces, urine, and laundry waste. This super polluted and ‘dirty’ wastewater is called sewage. So, what’s wrong with the sewage?
There are billions of people living on earth, and they all produce sewage every day. The problem is, sewage can be hazardous to aquatic environment. This is the reason why raw and unprocessed sewage is rarely let go into any water body.
So, since large amount of sewage is produced every day, how do aquatic ecosystems respond to it?
The Dirty Water
There are four main types of wastewater that we know. Those are: domestic, industrial, agricultural and urban. Each of those usually contains different matters, such as domestic wastewater consists of gray water from our activities like bathing, washing, and cooking, as well as human and animal fecal matter.
While industrial wastewater contains more industrial-like matters such as pulp, petrochemicals runoff, acids, and various kinds of chemicals and byproducts. While urban wastewater is the result of big cities activity. Thus the matters it consists is the combination of both types explained above.
There is another type of wastewater, the agricultural, which consist of mainly contaminated ground water. The contamination can come from fertilizers and pesticides, or other chemicals used in agricultural activities.
When channeled into wastewater disposal system, all of the contaminated and polluted water will eventually go into one connected place called sewer. In the sewer, all four types of wastewater mentioned above will mix into each other creating a ‘super contaminated’ sewage.
Sewage is so contaminated that it is possible to contain deadly bacteria, harmful chemicals, and other kinds of things linked to chronic and acute diseases. Not only that, it can also poison the environment too if it is not treated well.
So, what do we do with the sewage we produce, as we know that we produce a lot of sewage every day. almost every single water consumption that we do will apparently contribute to the forming of this super polluted liquid. In this case, who is the first to be affected?
Of course the environment closest to the ‘assembly point’, aquatic environment. As mentioned above, sewage contains various amount of pollutants, both organic and inorganic matters. On the other hand, aquatic environment is one of the most sensitive environments on earth that can be disturbed by smallest amount of pollutant present.
Not only that, we also don’t want sewage to enter our precious ground water. Thus it is treated in sewage management plants in three important phases. The first phase is about filtering solid waste and low-density materials it contains.
The second phase is removing dissolved and suspended organic materials in it using aerobic bacteria. The bacteria used in this process will consume the organic matters, including our and animal fecal matter dissolved in the wastewater.
The third phase is further treatment to make the water ‘releasable’ to sensitive environment like aquatic environment using various methods like sand filtration, nitrifying bacteria, and many others. Pretty long process for our daily wastewater, isn’t it?
The Aquatic Hazard
Coming to the fact that wastewater actually needs to be treated in such long and complicated process, it requires sophisticated technology. That’s why not all country in the world have such kind of wastewater treatment, because some countries are not as advanced as others.
The result is contaminated water bodies. Annually, in United States there are 3.5 million cases of people get sick from being in contact with contaminated water. That’s the number we can find in one of the most advanced country in terms of technology, what about other less advanced countries?
About 50% of sewage in being flowed to Mediterranean is untreated. It causes a phenomenon called hypoxic dead zone, where the oxygen in the water is depleted that no marine organism is willing to inhabit the area.
The reason for it comes from oxygen-depleting bacteria that consumes too much oxygen and leave almost none left for native organisms. Nutrient-rich materials from fertilizers can also cause algal bloom that will result in oxygen-depleted area.
Lack of oxygen is not the only thing that drives all those marine organisms away. In many cases, harmful chemicals and other destructive matters like microplastic can also be the cause for aquatic environment destruction.
Observe And Counter
Sewage needs to be handled carefully and thoroughly. Actually, every country has the ability to do it well despite their current knowledge and technology development. The first thing that they need to do is to educate people about wastewater management.
Not everyone knows where our wastewater goes and possibly goes to, let alone the impacts of its presence in the environment. Next, they should also know that there are various pre-treatment steps that everyone can do before flowing raw wastewater to sewers starting from our home.
In example, we can use composting sawdust toilet to treat our own ‘matters’. Not only it saves our sanitary water consumption, but it can also prevent us from adding up more organic ‘matter’ to the sewage and we can also get free fertilizer.
Another example is by composting our leftovers instead of sending it into our sink. Even though you use waste crusher in your sink, the organic matter will still go to the sewage system. Apparently, throwing your leftover to composting bins will give you dishes that are easier to wash, free compost, and slightly better world.
Proper environmental education and strict regulation are also important to reduce our industrial, agricultural, and urban wastewater production. Industry and agriculture sectors are even the biggest contributor to wastewater, looking on the level of water consumption.
Truly, the problem we are facing about how sewage affect aquatic environment is solvable. It depends on us whether we want to solve it or not. Well, of course we want to.