The Importance of Sewage Plants

Of all the field trips I have been on over the years, the trip to the sewage treatment plant has by far been the most interesting and educational. This trip really opened my eyes to the entire process, which our sewage goes through. Before this trip I knew only that our sewage was cleaned somehow, other than that, I knew nothing. Yes, in years previous, our science teachers had opened our eyes to how much water we use, and the costs, but this was the first time I have learned about the most important part of the cycle our everyday water goes through. After taking the metro bus from our school to magnolia, where I incidentally reside, we departed from the bus and into a small conference-style room inside Discover Park, where we met our tour guide, Greg.

In the entirety of king county there are two main sewage treatment plants, the one we visited was the Discovery Park plant. Altogether, the two plants handle 1.6-1.7 million people's sewage. On an average day, an average person uses 70-120 gallons of water per day, this results in the Discovery Park sewage treatment plant handling on average 100 million gallons of sewage per day. Even your garbage disposal leads to the sewer. Sewage water includes; water, toilet paper, feces, urine, vomit, oil, grease, shampoo, conditioner, hair, spit, soap, bleach, dirt, blood, sweat, food waste, toothpaste, and bugs. The Discovery Park sewage treatment plant can handle anywhere up to 400 million gallons of sewage per day, and on occasion, they do see that much. Sky rocketing sewage amounts are usually attributed to rain. Storm water inflow and groundwater infiltration make up about 44% of the total inflow during the winter months, which is more than any other type of inflow during these stormy months. This is because king county uses combined sewer systems, meaning that the storm drains on street sides lead to the same place as the water when you flush your toilet. Therefore, when there is excess rain, there is excess water in the sewage system.