City leaders tour several wastewater centers prior to Monday’s meeting

     Professional Engineering Consultants engineer Kevin Rood lowered a device called a Secci disk into a basin full of wastewater, measuring the water's clarity.
    "There's two foot, there's three foot, there's four foot," Rood said as the disk sank into the 12-foot-deep basin, referring to the levels at which the device was still visible. "There's five foot, there's six foot, there's seven foot."
    The black-and-white disk, used to monitor the depth of solid waste in the basin, dropped about 7 1/2 feet below the surface before it disappeared beneath the solids that had settled at the bottom. Then Rood hauled it back up out of the water.
    He said there is no single standard for clarity, as the monitoring process must be tailored to suit each individual wastewater treatment plant.
    Rood stood atop a clarifier at the Haysville wastewater treatment plant Thursday, explaining the plant's operations to a group of Dodge City commissioners and other observers. PEC is advising the city on a proposed water reclamation plant just north of the Dodge City limits.
    The group from Dodge City toured the Haysville plant and a newer water reclamation facility in El Dorado to learn more about them before Monday, when the commission will decide whether to purchase about 312 acres of land for the Dodge City plant. The Haysville plant was on the agenda because a residential area has grown up around it, and the El Dorado plant was included because it uses more up-to-date technology than the Haysville facility.
    A Globe reporter and photographer accompanied the group on the Haysville visit but did not go on to El Dorado.
    Commissioner Brian Weber said the tour improved his understanding of the issues involved in the Dodge City plant, and it made him more aware of what that plant might look like.
    "Now I can make a more informed decision when the time comes," he said.

Touring the plant
    The hourlong tour of the Haysville plant included a visit to the "head works" building, where raw sewage first enters the plant for processing. A strong but not overwhelming odor was noticeable within the unit, where screening devices removed large solid waste, trash and grit from the water.
    The 11-year-old plant can process up to 2 million gallons of wastewater a day and was designed so its capacity can be doubled to 4 million gallons, Rood said. It currently processes an average of 600,000 gallons per day.
    The group also visited the biological treatment process unit, which uses naturally occurring bacteria instead of chemicals or new bacteria to remove organic material, ammonia and nitrogen from the wastewater.
    "It's the same bacteria that nature uses in the streams and the rivers and the lakes," Rood said. "What we do is we provide an environment where it's able to grow and flourish, and so we can do in a matter of hours what nature takes weeks and months to do."
    He said the plant uses an oxygenated process — also known as an aerobic process — for handling the waste, which prevents hydrogen sulfides from forming and generating odors. Odor-eating microorganisms in the water also help control the smell.
    The water and sludge — another name for solid biological waste — are separated in clarifying tanks, where the sludge settles to the bottom and returns to the process to continue their work. Liquids overflow the clarifiers and are disinfected before they are treated.
    Part of the solid waste is periodically removed from the process and taken over to a digestion unit, where it is reduced further for another 40 days before land application.
    Rood said all those components would be incorporated into the Dodge City plant, with one exception. Instead of clarifying tanks, the Dodge City plant would filter waste materials through membranes, whose small pores would allow the membranes to retain viruses, bacteria and particulate solids.
    The Haysville plant includes backup systems in case of an emergency.
    Lab technician Keith Hill said about a month ago, the plant had a storm-related incident in which the "head works" unit took in more wastewater than it could process.
    "We had so much coming in that all we could do is really, you open up the head works and open all gates and let it flow," he said.
    Hill said the overflow went out of the building onto the grass, where it was later cleaned up. He added that the smell was not as bad as people might think — but he said that might be because he's accustomed to it.

Reactions
    Dodge City resident Mike Weber, who joined the tour, said Friday that the visit confirmed his opinion that wastewater treatment plants do not smell bad most of the time — but there are exceptions.
    "It also supported my opinion that occasionally, things go wrong because of acts of God or human failure or mechanical failure that cause smells to leave the plant," he said.
    Weber, who is the father of Commissioner Brian Weber, opposes the location of Dodge City's proposed water reclamation plant for two reasons: The potential odor, and the possible impact on future development in the area.
    As an alternative, he has proposed building the plant two miles directly east of the site currently under consideration. He pitched his idea to the commissioners during the El Dorado portion of the tour.
    Weber said Friday that his proposed site would be close enough to the city that the reclaimed water back to town for irrigation purposes, but it would be far enough away that it would not interfere with the city's development.
    "I believe the alternative proposal would benefit the city as a whole for several reasons," he said. "One, of course, is getting the negative stigma and likelihood of occasional odors east of the city and further away from the city."
    Weber also said his proposal would involve fewer lift stations and allow more sewers to gravity drain.
    Dodge City Vice Mayor Rick Sowers, who also joined the tour, said the experience was shaping his thoughts about where Dodge City's wastewater reclamation plant should be located.
    "I think that's probably our first task right now is, where are we going to locate this? Where does it make sense to locate it?" he said. "And there are a lot of considerations that are taken into that."
    Sowers said it was too early to form an opinion of Weber's alternate proposal.

Reach Eric Swanson at (620) 408-9917 or e-mail him at eric.swanson@dodgeglobe.com.