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Welcome to the Wonderful World of Wastewater
Some of the great mysteries in life are; where do elephants go to die; does the light really go off when you close the refrigerator door and where does the water go when you flush? In the movie "Finding Nemo", all drains lead to the ocean, but in Rolla all drains lead to one of three sewage treatment plants. The sewage plant is that forgotten place inhabited by a mythical civil servant known as the Wastewater Operator.
In all seriousness, wastewater treatment is an important and mostly forgotten service that the City of Rolla provides to its citizens. Few people know that the city’s wastewater plants process on average four million gallons of wastewater a day, every day! This mind-boggling task is accomplished with only seven full time employees and is unique from the standpoint that it is a 24-hour per day, 7 day per week, 365 day per year operation. And all of this is done using no tax money of any kind. This division is fully supported by user fees. The current user fee is $4.00 per 1,000 gallons, a rate that is below the average paid throughout Missouri. To put this in perspective, in a year’s time over 5,000 operational lab tests are run, 500 dry tons of bio solids are applied as soil conditioner/fertilizer and tons of paper work (okay, pounds) makes its way through the office. And all that with no tax money!
Treatment of wastewater takes place at three separate locations, the Southeast Wastewater Treatment Plant which currently handles roughly three quarters of Rolla’s sanitary sewer flow, the Vichy Road Wastewater Treatment Plant and the Southwest Wastewater Treatment Plant located on Martin Springs Drive. The process used to treat incoming wastewater occurs through aerobic treatment. What this means is air breathing microorganisms (fondly referred to as "bugs and critters") are used to break down the sewage and digest it. In fact, quite a bit of the wastewater operators job is tending to these little guys!
The main step in the process is separation of the solids from the water (wastewater is 98% water). This is done in two ways. First the wastewater is allowed to settle by letting it sit for a while. The second method is called bioflocculation (big word alert!). Bioflocculation is when the bugs and critters are introduced to a fresh food source and they grab onto it causing both the food and themselves to sink to the bottom of the settling tank. The question now is what do you do with the sewage after it settles? The answer is you pump the settled wastewater to another tank and put lots of air in it so the bugs and critters can breath while they are eating. The bugs and critters range in size from 12 micrometers to around 1 millimeter in length. The wastewater operator tries to keep a well-balanced community in the aeration tank by wasting (sending part of the microorganisms to another tank) and returning (sending part of the micro-organisms back to the same tank) and controlling the amount of air they get. After the microorganisms are fat and sassy, they are literally put out to pasture. Wastewater operators land apply approximately 1,000,000 gallons of bio solids
Now we will look at the clear water. The clear water is sent to the trickling tower. The trickling tower is another aerobic process that removes ammonia. The chemical formula for ammonia is NH3. Ammonia is mostly nitrogen, the main ingredient in protein. To remove ammonia we use bugs and critters that like protein (bodybuilder bugs and critters). After the trickling filter, the clear water goes to the sand filter. This is where very small particles are removed and sent back to the start of the plant to begin their journey again. Next, the water is tested to make sure that it meets State and Federal standards and it sent to the local waterways.
The heart of Rolla’s wastewater treatment strategy is its highly trained staff. A wastewater operator needs skills and training in biology, electricity, mechanics and a good working knowledge of wastewater treatment. Operators are licensed by the state. Rolla has five operators with an "A" license. To obtain this, the operator must have at least six years experience and pass a state administered test. Wastewater operators are stewards of the environment. The community of Rolla can rest assured that it will be protected as long as Rolla’s finest wastewater operators are on the job. (The wastewater division is part of the Public Works Department).
Wastewater Superintendent: William Olms
The Wastewater Division is subdivided into two primary areas, collection and treatment. The division is staffed with twelve individuals who perform various operation and maintenance activities at our treatment plants as well as cleaning and televising our sewage collection system.
Assistant Superintendent: Phillip Rosenburg
Eight members are assigned to the treatment operations of the division. They operate and maintain three mechanical plants and treat approximately 4.2 million gallons of wastewater per day.
This division's mission is unique in Public Works from the standpoint that it is a 24-hour per day, 7 days per week, 365 day per year operation. Treatment takes place continually. Staff members are on call at all times to respond to emergencies, and maintenance activities are performed on Saturdays, Sundays, and holidays at our treatment plants.
This division is fully supported by user fees. The current user fee is $5.15 per 1000 gallons (with a $5.15 minimum.) This rate is below the average paid throughout Missouri.
Group tours of our main plant off Highway 72 can be arranged by calling William Olms at 573-364-6122.
Sewer Collection Superintendent: Dennis Cook
Five members are assigned to the collection system maintenance and operations section of the Wastewater Division. They operate and maintain over 130 miles of sanitary sewer lines throughout the Rolla community. This division is also responsible for inspecting sewer taps and connections for any new sewer service in the city. In addition to serving the residents of Rolla, the division also serves several areas just outside the city limits and a portion of the City of Doolittle.
Like the treatment section of the division, this is an around-the-clock operation. A properly functioning sewer system is a constant necessity. Staff members are on call at all times to respond to emergencies, and maintenance activities are performed on Saturdays, Sundays, and holidays at our treatment plants.