Wastewater lagoons
Three lagoons at one works, all carrying enough accumulated material to put dredging on the capital plan.
reduction across the three lagoons in one year
01The plant
Three wastewater lagoons at one village works in Michigan's agricultural belt.
02Before
All three had accumulated enough material on their floors for dredging to have reached the village's capital plan, which is the point at which a lagoon works stops being the cheap way to treat wastewater.
03Treatment
A programme run across all three lagoons over a year, with the object of taking the accumulated volume down far enough to defer the dredging rather than cancel it.
Every result in this library was measured at an operating plant treating with one of the formulations SediLogic supplies, over the window stated above. It is a field result published as reported, not a controlled trial we ran.
04Method
Sludge maps of each lagoon made before the programme and again at the end of the year, so each of the three has its own before-and-after rather than a works-wide figure.
05Outcome
Dredging deferred at all three lagoons.
06Limits
The spread is the thing to read here, and the record does not explain it: forty per cent at one lagoon and ninety-one at another, in the same year, at the same works, under the same programme. Three cells fed by one village should not behave that differently unless what was on their floors was different to begin with, and no volatile fraction is published for any of them. Nothing was left untreated, no dates or water temperatures are given, and the maps are stated to exist rather than described. A number at the top of that range is not what a fourth lagoon should expect.
Only the volatile organic fraction of a sludge responds to any of this. Grit, sand, silt, mineral precipitates and plastics remain at any dose, here and everywhere else.
—What we would supply
This is the duty SediLogic supplies and sizes. Which article depends on where the material sits: Sedivore Spike is the denser solid and carries down through depth to an established blanket, Sedivore Puck is a smaller unit that spreads a calculated dose across the bed, and SediLogic Maintain is a soluble pouch for load carried in the water column — with Sedivore Polar for that same duty where the water runs cold enough to stall a standard blend.
A quantity for your own lagoon comes from the dosing planner, sized against your dimensions and loading from the manufacturer's written dose method. It does not come from the figure on this page, which was set for a lagoon that is not yours.
—Read next
Wastewater lagoons
Municipal24 weeks
of accumulated solids digested
Just over five feet of accumulated solids in the primary aerated lagoon, assessed at 2,365 dry tons. The plant wanted a route that did not involve dredging.
Wastewater lagoons
MunicipalFive months, May to October
reduction in solids volume overall
Accumulated solids across two lagoon cells, against a specification calling for a 50 per cent reduction. The treatment window was bounded by water temperature, which has to stay above roughly 55°F for the organisms to work at all.
Wastewater lagoons
Municipal3 months
of organic solids digested
Decades of loading had taken the lagoon to a measured 20.5 per cent solids, with a dredging quotation in hand and no budget line to meet it.
Your lagoon next
A different plant, a different loading and a different sludge. What decides your result is how much of your own accumulation is organic and treatable, and whether the dose is sized against the lagoon in front of us rather than read off this page. Tell us the dimensions and we will size it.
