---
url: https://www.eurocovers.eu/solutions/sludge-reduction
title: Sludge reduction for wastewater lagoons
description: Bioaugmentation digests the treatable organic fraction of lagoon sludge in place — deferring dredging. Sized to your lagoon, honest about limits.
updated: 2026-07-26
---

# Sludge reduction for wastewater lagoons

Bioaugmentation digests the treatable organic fraction of lagoon sludge in place — deferring dredging. Sized to your lagoon, honest about limits.

For EU lagoon operators, sludge reduction by **bioaugmentation** means digesting the
treatable organic fraction of the sludge blanket in place — turning a seven-figure
mechanical clean-out into a managed operating-cost line. EuroCover supplies the
[SediLogic® range](/products/sedilogic) for this brief, sized to your lagoon by the
manufacturer's dose table, with the honest caveat stated up front: biology treats the
organic fraction only, and we will tell you when your lagoon is a dredging job instead.

## What is sludge reduction?

**Sludge reduction** is shrinking the accumulated blanket of settled solids at the bottom
of a lagoon or tank before it consumes detention time, freeboard and effluent quality.
Solids settle continuously; the biodegradable share digests slowly under anaerobic
conditions; what is left accumulates. Sludge handling already represents 40–60% of total
operating cost at many treatment facilities, and an unplanned mechanical clean-out is the
largest single capital event a small utility faces on a lagoon.

## How bioaugmentation works

The SediLogic® formulation is a Bacillus-sourced enzyme blend — protease, cellulase and
lipase — supplied as a dry product (Bacillus sporulates, so it survives drying essentially
intact):

- **Sinking solid (SediLogic® Core)** — dosed onto an established blanket, sinks to the
  sludge interface where the accumulation actually sits.
- **Water-soluble pouch (SediLogic® Maintain)** — maintenance dosing and general organic
  load in the water column, for adequately mixed lagoons.

The organisms digest volatile organic solids in place. Published volatile solids reductions
in this category run from roughly 33% in controlled enzyme studies to around 60% in vendor
case studies.

## What it cannot treat

Sand, grit, silt, mineral precipitates and plastics are **not biodegradable** — they remain
at any dose, from any vendor, in any format. The split between volatile and inert material
differs in every lagoon, which is why a representative sludge sample is the first step of
any honest programme. If your accumulation is mostly inert, the answer is dredging, and we
will say so before you spend anything.

## Benefits of a sized programme

| Metric | Value |
|---|---|
| Volatile solids reduction | 33–60% |
| Sludge handling share of operating cost | 40–60% |
| Mechanical dredging benchmark | $300–800 / dry ton |
| Full mechanical clean-out | $875K–$1.75M (estimated) |
| Product-spend trim from lagoon sizing vs rule of thumb | 5–20% |

## When to use bioaugmentation

- Municipal and industrial wastewater lagoons with a measured sludge blanket
- Operators facing a dredging quote who want to defer the capital event
- Sites with rising haulage costs on sludge holding and thickening tanks
- Lift stations and grease interceptors with fats, oils and grease accumulation
- Anaerobic digesters where volatile solids loading governs destruction rate

## When not to use it

- Accumulation that is mostly inert grit, sand or silt — that is a dredging job
- Poorly mixed lagoons — aeration comes first; biology follows
- Compliance emergencies that need volume back this month, not this season

## The evidence, stated plainly

Every efficacy figure in this category is vendor-published — including the ones we cite.
No independent head-to-head comparison of liquid versus solid formats exists, and
penetration into a dense anaerobic sludge mass remains an unsolved problem for every
format on the market. What is well established is narrower: enzyme mixtures of protease,
cellulase and lipase reduce total suspended solids by 30–50% and improve settling. That is
the mechanism we sell, and it is a narrower claim than most of this category makes. The
manufacturer publishes the full evidence review at
[lagoonsludge.com](https://www.lagoonsludge.com/).

For the complementary water-management briefs, see
[odor and emission control](/solutions/odor-emission-control) and
[evaporation control](/solutions/evaporation-control).