Gratitude for Wastewater Treatment Plants
We flush away our waste with just a push of the toilet handle. Our dirty sink and bathwater flow down the drain without any effort on our part. Obviously, the wastewater does not simply disappear. Instead, it flows into the sewage system and is directed to a wastewater treatment plant.
Wastewater treatment plants are an essential part of our infrastructure. They protect our quality of life and the environment. Without wastewater treatment plants, our way of life would be dramatically affected. Yet, the sewage system and water treatment work so well that they are essentially invisible to most of us. Thankfully, we’ve come a long way in wastewater systems because even our recent ancestors’ waste used to be a very visible, stinky, and dangerous problem.
Life Before Wastewater Treatment Plants
Human waste has been an issue since the first concentrated settlements sprang up in areas of production and commerce. A lot of people means a lot of waste. The first sort of sanitation facility was a sump or cesspit—basically a cistern for “excreta”—in 4000 BC Babylon. Eventually, some cities developed sewer systems that connected latrines in people’s homes to the cesspits.
However, in many cases cesspits were full to overflowing. Plus, not all civilizations had sewer systems, as there was a loss of knowledge about sewer systems as civilizations declined. So, in Shakespeare’s Middle Ages, the Renaissance Period, and even 18th century New York City, people would often dump their waste into the street. Unimaginable today, this was the norm then! In 1724, a New York City ordinance made it illegal to dump human waste into the street; residents had to walk to one of the rivers to dump their waste instead. Imagine carrying your chamber pot through Manhattan to the Hudson River and bumping into someone you know along the way…
Although there were some advances in sewer systems, there was not any kind of water treatment until the late 19th century. Instead, sewer systems emptied untreated wastewater into cesspits or the city river.
How Wastewater Treatment Plants Handle Wastewater
Fortunately, we have wastewater treatment plants today. Wastewater goes from drains and toilets in our home to the sewer system to the wastewater treatment plant (WWTP). The WWTP then cleans the wastewater through a combination of physical, biological, and chemical processes.
The wastewater treatment process involves a few steps:
- Primary Treatment: Removes waste through physical mechanisms, such as screens to remove debris and settling tanks with arms that scrape solids from the bottom and skim grease floating at the top.
- Secondary Treatment: Uses beneficial microorganisms to turn organic material in the wastewater into other forms that can be separated from the water.
- Tertiary Treatment: Employs further filtration, chemical treatment, and/or UV exposure to remove the final contaminants. Not all WWTPs do tertiary treatment, but it has become common as plants must meet stricter effluent limits for certain contaminants.
Wastewater Treatment Plants Improve Our Quality of Life
Looking back at history, it is undeniable that wastewater treatment has greatly improved our quality of life in a few ways:
We don’t have to worry about what we’re going to do with our waste and wash water. Frankly, we should be thrilled that we don’t have to mull over if it’s worth walking to the river to dump our chamber pot or whether we should just pitch its contents out the window. I bet most of us never even think about what happens to our waste. It only becomes a temporary issue again if we have a clogged drain.
Whether human waste is stagnant in a cesspit, slung into the street, or dumped in the river, it is going to be filthy. For example, in what is known as the “Great Stink” of 1858, the stench in London became unbearable as the summer sun simmered human waste in the River Thames. All activity in the city screeched to a halt and people fled if they could. The crisis spurred a complete overhaul of the dysfunctional sewer system to a highly engineered system that moved waste out of the city. Today, wastewater treatment plants discharge exceptionally clean reclaimed water into rivers and streams.
Living in an environment full of human waste and dirty water is obviously not healthy. Throughout the thousands of years in densely populated areas without sanitation systems, there were many outbreaks of disease, such as cholera. It took a while to connect many of the epidemics to drinking water sources that were contaminated with wastewater. Today’s sewer system brings wastewater away from our living quarters to wastewater treatment plants to be dealt with safely.
Wastewater Treatment Plants Protect the Environment
At the same time, wastewater treatment plants clearly protect the health of the environment. As mentioned early, reclaimed water is remarkably clean by the end of the treatment process. According to Metropolitan Water Reclamation District of Greater Chicago (MWRD), their “reclaimed water has more than 95% of the impurities removed and can be deposited into a river or stream without any adverse environmental impacts.” Therefore, wastewater treatment plants are important protectors of the local environment. We’ve thankfully come a long way from dumping our waste directly into rivers!
However, there are a few combined sewer overflow (CSOs) systems in our area. Combined sewers carry both wastewater and stormwater to a wastewater treatment plant. During heavy rain events, the combined flows exceed the capacity of the WWTP, so a combined sewer overflow system will discharge the excess into a local waterway. In these cases, a mix of untreated stormwater and wastewater ends up in the river or stream. While most CSOs have been phased out, there are still a few in older communities that have occasional overflow issues.
Thank Goodness for Wastewater Treatment Plants
Modern sanitation is a very convincing reason why we are fortunate to be alive today. In fact, only about .04% of human’s time on earth has existed during the time of wastewater treatment.
Sewer systems and wastewater treatment plants improve our quality of life in many ways, making what happens to our waste an essentially invisible operation for most of us. With improved sanitation came a decline in illness as well as a decline in likelihood that you’ll step into human excreta on the street. Thank goodness! And, let’s not forget that modern wastewater treatment protects clean water in our local waterways. Receiving clean effluent from WWTPs, our local rivers aren’t in danger of another crisis like the Great Stink.
Again, our wastewater professionals perform an essential service for our community. Plant operators and engineers are in high demand as many skilled operators are retiring. Because of their expertise and importance to our quality of life, plant operators are well-paid, receive good benefits, and have stable jobs. If you know a young person seeking a career path or someone contemplating a career change, working in wastewater treatment is a great choice!