Following a conversation with a friend who is a wastewater plant manager at the South Valley Water Reclamation Treatment Facility, South of Salt Lake City, Utah; I asked if I could have a tour of the facility and learn more about its operation. A committee member of ASCE YMF, Abraham Lopez – Water Resources Engineer, and I – Jenna Jaye, visited the facility for a two-hour tour.
I’ve been very fortunate in my career to land where it’s taken me. Starting out in Structures and then migrating over to Transportation have been two areas I’ve been passionate, and which I have also studied during my thesis at University. However, there is one area I always enjoyed during my years at University, which was wastewater treatment. ‘You mean you like to learn about sewage?’ – I guess someone must, is usually my response. No, but really, there’s just always been something in that subject that I gravitated to the most out of all the subjects I studied at University. If I begin to dissect this a little further, perhaps you’ll see or begin to understand why wastewater treatment can genuinely be a riveting part of civil engineering.
Imagine, your local wastewater treatment plant suddenly malfunctions, and cannot be repaired before the backup generator burns out. What would happen? People don’t stop flushing the toilet, and so with thousands of citizens reliant upon a system of wastewater treatment, you need to be able to maintain a system and understand everything that comes in and goes out of it. As a wastewater engineer you’re serving society, it’s a role that is fundamental to the functioning of a community. Centuries ago before the technology available in our age existed, I often wonder how those communities dealt with their waste. Their inability to deal with waste may explain a lot of widespread disease, and so with developments in technology and population growth we have miraculously used nature and found ways to serve much larger populations.
The idea of a closed system, where a team controls the treatment, from the influent entering a system and to the release of effluent back into our rivers. The concept of a closed system differs to the typical work I’ve undertaken in Highways design until now. In their simplest form Highways are lines through the natural environment which we carve into the landscape – until they meet a junction, they are ongoing and are fundamentally designed as continuous. A section of highway has somewhat more or less similar features: crown, shoulder, drainage, striping etc. In contrast to such open-ended design, a sewage treatment system or any processing plant for that matter, has a beginning where raw material enters and an end where a product is produced. There are hundreds of types of processing plants, from steel smelters to oil refineries. What distinguishes wastewater treatment plants, from other processing plants, for me, is that wastewater treatment is needed by every one of us. It doesn’t have a preference, it serves every one of us, and especially not it’s primary shareholders who own stock in the company. Don’t get me wrong, oil and steel are raw materials from which many products necessary in our lives are produced, however there are alternate resources we know of that are sustainable and better for the population.
Furthermore, if we think about the science involved in wastewater treatment, it is the only discipline in civil engineering which utilizes parts of biology, chemistry and physics. The three sciences work together to neutralize our waste and enable it to flow back into our rivers. Wastewater is treated biologically, by processes known as aerobic and anaerobic digestion. Microbes need two components to thrive, which are, food and oxygen. The food they receive is the waste, the influent, and the oxygen is blasted in via enormous air pumps which feed the ditches which they flow through. During the lifecycle of microbes, they break down the sewage converting a large amount of it into phosphate and nitrogen which is released into the atmosphere, by a process is known as nitrification. Toward the end of the wastewater treatment process, before the treated water can be released into the river, the microbes are sterilized chemically. This process is known as chlorination, which disinfects the effluent by the addition of chlorine and other small chemical quantities. There are Physics concepts involved all around a wastewater treatment plant. One which is most notable to me is the facilities gravitational design. Wastewater treatment facilities are designed to be energy efficient and reduce their reliance and dependence upon pumps as much as possible. Energy costs can largely be reduced by the conversion of potential energy to kinetic energy, by the flow from a high to a low point in the system.