Treatment Plant Discharging Cleaner Water Into Pine
https://secure.gravatar.com/avatar/cd916b5b8cd34e22a3b27b7534834d43?s=21&d=mm&r=gPosted on Wednesday, January 16th, 2019 and is filed under News. You can follow any responses to this entry through the RSS 2.0 feed. You can skip to the end and leave a response. Pinging is currently not allowed.
The City of Alma’s Wastewater Treatment Plant is locatated at 1000 Washington Ave. Plant superintendent Daren Johnson has been working on methods to discharge significantly cleaner treated water into the Pine River.
Nitrogen Levels Have Been Decreased by a Minimum of 40 Pounds Per Day
By Rosemary Horvath
Herald Staff Writer
New “leading-edge technology” installed at the Alma wastewater treatment plant should reduce the growth of aquatic plants and algae in the Pine River.
[private] City Manager Matt Schooley reviewed the positive prospects during the city commission work session last week stating, “We do have challenges in our river and we are doing our part.”
A report provided by Public Utilities Director Alan Leute and Wastewater Treatment Plant Superintendent Daren Johnson acknowledged the city is working toward a “significantly cleaner discharge.”
So far, the improvement exceeds anything seen in the last 20 years.
Phosphorous in the discharged water has been as much as 0.4 parts per million less and well below the 1.0 ppm the city is permitted to release under the Michigan Department of Environmental Quality permit. Nitrogen levels have been decreased into the river by a minimum of 40 pounds per day.
Nitrogen and phosphorous are responsible for the overstimulation of growth of aquatic plants and algae.
Leute attributed the progress to Johnson who has been at the plant for 20 years and is learning new processes from research.
Johnson has been retrofitting an old plant with new technology. “The beauty is we are doing this without increasing any chemicals,” Johnson told the Herald.
New meters and electrodes provide on-site analyses of oxidation-reduction potential and nitrates.
Technically, this led to switching “from the historical mode of operation to include Anoxic and Anaerobic Selector Processes. By cycling through basins of aerobic (adding air), anoxic (without added air) and anaerobic (without added air, plus sufficient detention time to reduce all oxygen), the microbes have been naturally removing nitrates and phosphorous in our wastewater stream. This leading-edge technology increases plant efficiency, produces a cleaner effluent, reduces sludge production and helps to control filamentous bacteria (still working to fully achieve this benefit).”
Reducing the levels of phosphorous has been achieved without the use of ferric chloride for treatment, which saves the city $10,000 per year in chemicals alone, plus lowers the electricity costs.
For example, Johnson said in the 2015-2016 budget year, the plant used 18.2 tons of ferric chloride. The amount for part of the following budget year was 13 tons until usage dropped to zero.
“We are better than halfway where we need to be,” cautioned Johnson, adding that he is in the process of learning new techniques for controlling biological growth and facilitating treatment.