The mud never leaves the lake.
That single design decision removes the disposal site, the land acquisition, the hauling of contaminated sediment across the state, and most of the cost.
Four stages, one continuous cycle
Collection
Solar-powered pumps draw fluid mud from an outer sediment trap into the lagoon interior.
Settling
Sediment consolidates inside the lagoon, gradually forming new land.
Phytoremediation
Native vegetation draws additional nutrients from the water as new land matures.
Discharge
Water passes through a sand, rock, and limestone filter before returning to the lake.
How It's Built
An engineered ring island, built in the deepest part of the lake from material excavated on site.
- Sediment A trench on the lake floor captures fluid mud, which flows and migrates into it.
- Emergent The central sequestration area. High-nutrient mud settles and consolidates here. It functions as a bioreactor covered with floating aquatic vegetation, with a 21-day residence time for particles to settle.
- Tussock Limestone. Wave reduction, sediment capture, and coprecipitation of phosphorus. They build proto-peat filtration over time.
- Tussock Floating plant rafts that act as an aquatic vegetation barrier and capture suspended solids, providing substrate for willow, cattail, and other natives.
- Backwash A calcium carbonate, sand, and rock filter. The fourth stage of treatment as water leaves the marsh.
- Land Sediment retention and secondary wave attenuation. Carries the solar panel fields and the vaulted mud and backwash pumps.
- Diffusion Holds the highest quality water of the five treatment rings, in preparation for release back to the lake.
- Corrugated wave barrier. A limestone structure providing the final stage of filtration, biological uptake, and phosphorus coprecipitation before water re-enters the It also pre-filters backwash water entering the lagoon.
How It Runs
Solar. Pumping runs on solar panel fields on the land ring. During the day, pumps move mud inward from the sediment trap. At night, pumping stops and filtered water drains outward under its own head. There is no continuous heavy machinery.
Five stages of treatment. Water passes through the marsh, the tussock ring, the backwash filter, the diffusion zone, and the corrugated wave barrier before returning to the lake.
Permanent. As sediment layers accumulate, the surface reaches sunlight and becomes marsh. The nutrients underneath are buried and no longer resuspendable by wind or wave. The area shifts from algae-dominated to plant-stabilized.
Conventional dredging compared
| Conventional dredging | Diatom Lagoon | |
| Where the mud goes | Barged or piped to an upland site | Sequestered inside the lake |
| Land acquired | Large upland disposal acreage | None |
| Farmland taken out of production | Possible | None |
| Handling of mercury, arsenic, pesticides | Transported and stored on land | Stays in the lake bed, buried |
| Energy | Continuous heavy dredge operation | Primarily solar, low-head pumping |
| End state | A spoil site | Emergent marsh and wildlife habitat |
| Does it end? | No. Nutrients keep arriving. | The lagoon keeps working as they arrive. |
Questions We Get
Why this approach is different
In-lake sequestration
Nutrients are collected, contained, and processed entirely within the lake. No land acquisition or off-site landfill required.
Continuous treatment
Collection, transport, and sequestration operate continuously and can remain in service essentially indefinitely.
Minimal process disturbance
Sediment capture happens within the outer trap under a low-gradient environment, minimizing dispersion through the water column.
No chemicals
Natural mechanical deposition and filtration, paired with phytoremediation, do the work. Nothing is added to the lake.
Habitat creation
New shoreline and land mass created through the process supports habitat for birds and aquatic species.
Renewable power source
The system is designed to run on solar power for the pumps required for operation.
A Complement, Not a Competitor
Chemical treatment binds phosphorus in the water column and can temporarily clarify it, but rather than removing the legacy sediment, it settles on top of it, where storms can resuspend it, and it does little or nothing for nitrogen. Diatom Lagoons remove that legacy phosphorus, nitrogen, and particulate load from the system permanently. By removing the pollutant load rather than just masking it, they increase the lake's usable water storage, and the clarity this creates lets light reach the bottom, giving submerged aquatic vegetation the conditions it needs to recover. Where chemical treatment offers a temporary fix for one symptom, Diatom Lagoons solve storage and water quality together, permanently.