Contact Find a distributor

Request a quote

Be contacted by a TASO counselor

    I would like to be contacted by:

    Send
    Illustration of green water

    Siltation & loss of seabed

    siltation, loss of seabed 1 1

    What you see

    The physical profile of your body of water is changing. The signs of siltation are obvious:

    • Loss of depth: The riverbed is rising year after year. Areas that were once navigable or suitable for fishing are now above water
    • Soft, "bottomless" mud: A pole or oar sinks several dozen centimeters without encountering any firm resistance.
    • Visible fermentation: Gas bubbles rise to the surface (methane) in the summer. When the bottom is disturbed, the water turns black and gives off a characteristic rotten-egg smell (hydrogen sulfide).
    • Emergence of islands: Mudflats or patches of vegetation appear in the center of the body of water, altering its banks.

    What this means

    Siltation is not just an accumulation of dead leaves; it is a symptom of bottom suffocation. TASO diagnoses this as Active Organic Sedimentation.

    The natural cycle of decomposition is disrupted:

    1. Anoxia (Lack of Oxygen): The bottom layer is deprived of oxygen. Aerobic bacteria die.
    2. Anaerobic Fermentation: A bacterial community responsible for putrefaction takes over. Instead of mineralizing the material (breaking it down into inert gases and minerals), it stores it in the form of acidic, unstable sludge.
    3. The Nutrient Trap: This sludge stores massive amounts of phosphorus and nitrogen, which are released into the water as soon as the temperature rises, feeding the algae.

    Conclusion: Your pond isn’t draining; it’s becoming clogged. It’s accumulating more organic matter than it can break down.

    siltation, loss of seabed 2 1

    Need to confirm the issues with your body of water?

    Contact a TASO expert

    Why act now?

    Siltation is an exponential process (the more silt there is, the less oxygen there is, so the silt accumulates more quickly). Failure to act leads to:

    • Mechanical Dredging (Cost and Impact): If the sediment becomes too dense or mineral-rich, the only solution is mechanical dredging (using excavators and trucks). This is an extremely costly operation (10 times more expensive than biological dredging), destructive to wildlife, and subject to complex regulations (management of dredged sediment).
    • The “Phosphorus Bomb”: A layer of anaerobic sludge acts as a reservoir of internal pollution. It will continue to feed cyanobacteria and filamentous algae for decades, even if you cut off external inputs.
    • Health and fish-related risks: The fermentation gases (H₂S, NH₄) produced by the sludge are toxic to fish and benthic fauna.

    The TASO Solution
    Biological Dredging (Bio-Dredging)

    Before considering major construction projects, TASO proposes reactivating the lake’s natural treatment system. We convert the sludge into water and inert gas.

    1

    Mineral Stimulation (Chemical Tillage)

    First, the acidity must be neutralized and the sludge oxidized to make it “digestible” by bacteria.

    How it works: When applied, Nautex (coccolithic calcium carbonate) penetrates the mud layer. It raises the pH and delivers dissolved oxygen deep into the sediment.

    The result: The sludge oxidizes, changes color (from black to gray/brown), and breaks down.

    2

    Bioaugmentation (Digestion)

    We bring in a team of skilled workers.

    The process: Inoculation with specific bacteria selected for their ability to break down complex carbon chains (cellulose, leaves, manure).

    The result: The organic matter is "consumed" and converted into CO2, which is released naturally. The volume of sludge is physically reduced.

    3

    Oxygen Support (Ventilation)

    For these bacteria to work at full capacity, they need oxygen.

    The procedure: Installing a bottom aeration system (Oxylake) is often essential for maintaining a continuous digestion process.

    Request an assessment


    Products & Related Solutions

    To reduce silt without using excavators:

    oxylake

    Oxylake

    Oxygenation solutions for ponds and bodies of water
    Learn more
    biolimpid

    Biolimpid

    Biological sedimentation
    Learn more
    nautex

    Nautex

    the standard mineral treatment for all bodies of water
    Learn more

    Need a study?

    Each protocol is tailored to the initial assessment, the characteristics of the body of water, and its intended uses.

    Request an assessment