DECATUR -- The Decatur wastewater treatment plant is going through a series of growing pains as the city undergoes changes in the amount of "flow" being sent to the plant. As a result, the plant has weighed heavy on the minds of city officials over the last year, and the status of the plant was reviewed at the special council meeting May 17.
In 2013, Decatur signed an agreement to take the city of Centerton's wastewater. This allowed Centerton to acquire bonds and build a pipeline connecting the two cities.
"At that time, the plant receiving the extra gallons per day made sense as we understood there would be enough untapped capacity for normal and natural growth," said Mayor Bob Tharp. "So we marched on."
From 2013 until October 2015 when the pipeline went online, city officials did not realize that the daily flow into the wastewater plant grew at a significantly larger rate. Suddenly, capacities became a major issue.
During the heavy rain event of Dec. 26, 2015, when the area was inundated with more than 14 inches of rain in a three-day period, problems began popping up in the city's storm-water management system. More storm water was migrating into the plant which did not need treatment, and that flow magnified the capacity issue.
The city crews, working long hours, identified the problems and began work to repair the system. That work is nearing final completion.
The flood waters of 2015 and 2016 continued to plague the wastewater plant. With unleashed storm water, in the form of extra capacity, the plant became unbalanced and city officials shut down the Centerton line until the plant stabilized.
The performance of the wastewater plant has reached a manageable level over the past six months, allowing city officials to bring the Centerton system back online.
"Centerton is a paying customer to Decatur just like any other sewer customer and we value them as a customer," Tharp said. "The additional revenue from the city of Centerton is positive for the city of Decatur and I continue to see the 2013 decision as a good one."
Tharp reported to the council that two significant needed improvements have been identified. One was recently completed, and another is to be completed in yet this month. These improvements will significantly reduce storm water from entering the wastewater plant and thus reduce the processing load.
With the capacity issue looming large over the plant, Tharp called a special council meeting in November to consider a design-build team to evaluate the wastewater plant with the hope of finding a better solution for wastewater processing.
On Dec. 14, 2015, Tharp called a second special council meeting to establish which design-build team to select. Later in the evening during the regular meeting, the full council ratified the decision to use Crossland Heavy Construction and McClelland Consulting Engineers, Inc.
During January and February, the team collected information and, in March, the city began to research ways to expand the existing system without the added cost of building new structures. James Boston, city water director, Mayor Tharp and the design-build team, looked at three systems (including the existing system), mechanical clarifiers and a membrane system commonly referred to as MBRs. The latter was seen as the best for the Decatur plant. The membrane system could be added to the existing system with virtually no new construction.
The membrane system is currently in use at the water treatment facility at Greer's Ferry in Arkansas.
"MBR systems are in use all over the world and provide the best water treatment possible for drinking water and wastewater plants," Tharp reported.
Recently, city officials met twice with officials with the Arkansas Department of Environmental Quality in Little Rock to find the best solution for Decatur.
"We were very honest and forthright with the ADEQ officials, explaining to them that we are working on several ideas to best resolve our issues," Tharp said. "We outlined that the city has a design build team in place and that we have isolated several corrections to our sewer system in Decatur that will make a difference. We also outlined the city's timeline in making all corrections and we did share with them our idea of the MBR system."
General News on 06/15/2016