Posted 12/15/15 (Tue)
By Amy Robinson
Farmer Staff Writer
With the addition of 20,000 gallons of sludge containing live micro-organisms and biology, Watford City’s new Mechanical Wastewater Treatment Plant was turned on Thursday, Dec. 3.
According to Justin Smith, Watford City Public Works superintendent, it takes live micro-organisms of various ages, and a lot of them, to digest and consume a majority of the organic material before Watford City’s wastewater can enter a clarifier to be disinfected and neutralized, and then it is safe to be released back into Cherry Creek.
“The whole Wasterwater Plant start-up is a two to three-month process,” stated Smith. “But the first step was to start diverting part of the wastewater into the oxidation ditch, which has started to grow some bugs, or biology/micro-organisms. The wastewater treatment process is ‘activated sludge’ and the configuration that process is adapted to, is called an oxidation ditch for our installation here.”
“Really, it’s basically the same stuff you learn about in seventh grade biology,” says Smith. He says in this start-up phase, they have diverted a portion of some wastewater flow into the oxidation ditch to start growing micro-biology.
“The project is supposed to be done by the end of December,” Smith stated. “Since it has gotten colder, and to get the process done faster, we have had to import about 20,000 gallons of sludge (with live micro-organisms and biology) from the Williston Wastewater Treatment Plant to speed up the process. And we’re also feeding some additional nutrients to the bacteria to help them grow faster.”
Currently, the discharged water is being held in a holding pond and will be held there until the city meets its permit limits for discharge. Along with the city’s approval to operate the new mechanical wastewater treatment plant from the North Dakota Department of Health, the city was required to meet a new wastewater discharge permit.
“Once we meet those required limits, which we expect to meet by the end of the year, we’ll start discharging to Cherry Creek,” says Smith. “The detention time through this process is about 72 hours, but we’re basically using equipment and energy to speed up what would normally happen in a lagoon pond by a factor of at least 20 times faster. That’s pretty significant. And we do that by using electricity to run equipment to add oxygen to the wastewater, and it requires additional labor to operate the equipment as compared to a lagoon, or holding pond.”
According to Smith, the sewer collection system is still growing as new infrastructure is commissioned. In 2016, the city will be offsetting some of the extra expense by reducing maintenance frequency on some of the piping in exchange for the additional infrastructure.
In 2015, the city commissioned two additional lift stations, and in 2016, the city expects to commission at least three more.