Dam Sealing & Repair for Mining and Farm Dams

Dam Sealing and Repair: Polymer Solutions for Leaking Mining Water Storage and Farm Dams

Australia has an estimated two million farm dams providing water for irrigation, stock watering, domestic supply and fire-fighting across rural properties. The mining industry operates thousands of additional water storage dams, sediment retention dams, environmental containment dams and process water dams. Together, these structures store the water that agriculture and mining depend on for survival and production.

When a dam leaks, the consequences range from inconvenient to catastrophic. A farm dam losing water through seepage may fail to sustain stock through a dry summer. A mining water storage dam losing process water reduces the operation’s water recycling efficiency and may require additional extraction from bore fields or surface water sources. A tailings dam with embankment seepage creates a safety, environmental and regulatory risk that demands immediate attention.

The traditional repair for a leaking earthen dam involves draining the remaining water, mobilising earthmoving equipment, identifying the leak path, excavating and recompacting the failed section, and refilling the dam. This process costs thousands to tens of thousands of dollars, takes days to weeks, wastes the water that remains in the dam, and — critically — often fails because the same material and conditions that caused the original leak are present in the repair.

This article covers why dams leak, why conventional repairs frequently fail, and how polymer dam sealing provides a faster, cheaper and more reliable alternative for both mining and agricultural applications — without draining the dam, without earthmoving equipment, and without the failure modes that make conventional repairs unreliable.

Why Dams Leak: Understanding the Failure Modes

Dam leaks are not random. They result from specific failure modes that are well understood but often poorly addressed during construction or repair.

Inadequate clay content or compaction. The most common cause of farm dam leakage. If the embankment material does not contain sufficient clay, or if the clay was not compacted to the required density during construction, the dam will leak through the embankment wall from the day it fills. Research on South Australian farm dams found that the majority of randomly selected hazardous dams were in unacceptable condition, with owners having ignored warnings about structural deficiencies for up to 15 years.

Dispersive (sodic) soils. If the embankment material is dispersive, the sodium-dominated clay dissolves on contact with fresh water, creating internal erosion tunnels (piping) through the wall. This is among the most dangerous failure modes because the tunnelling progresses invisibly until the wall collapses. Article 55 covers dispersive soil engineering in detail.

Cracking from wet-dry cycling. Expansive clay embankments crack during dry periods as the clay shrinks. When the dam refills, water enters the cracks and creates preferential flow paths through the wall. Each wet-dry cycle widens the cracks and worsens the seepage.

Tree roots and animal burrows. Tree roots growing into the dam wall create pathways for water to follow. When the root dies and decomposes, it leaves a hollow tube through the embankment. Animal burrows — wombats, rabbits, yabbies — create similar conduits. Both are common on farm dams and are frequently the proximate cause of seepage.

Foundation seepage. If the dam is constructed on permeable material — fractured rock, sandy soil, gravel layers — water can escape beneath the embankment through the foundation rather than through the wall. This is common in areas with shallow bedrock or geological discontinuities.

Pipe and outlet failures. Outlet pipes, spillway structures and any penetration through the embankment create an interface between the pipe and the surrounding fill. If this interface is not properly sealed during construction, water follows the pipe through the wall, eroding the fill material and creating a progressive leak around the pipe.

Why Conventional Repairs Often Fail

The conventional repair methodology — drain, excavate, recompact, refill — has inherent limitations that result in a high failure rate:

The repair uses the same material that failed. Unless new clay is imported (expensive, particularly in remote locations), the repair material is the same material that leaked originally. If it lacked sufficient clay content or was dispersive, the repair material has the same deficiency.

Compaction at the repair interface is imperfect. The joint between the original embankment and the repair fill is a construction interface — a plane of weakness where the compaction of the new material against the old is never as good as the compaction within the original wall. Water finds this interface and the leak reforms along it.

The root cause may not be identified. As Big Ditch Aquatecture emphasises, a leaking dam is not one problem. It can be seepage through poor clay, a failed core, a leaking pipe, a rock seam, animal holes, erosion, or evaporation being mistaken for a leak. If the repair addresses the wrong cause — recompacting the wall when the leak is through the foundation — the repair fails and the money is wasted.

The dam must be drained. Draining wastes the remaining water, which in drought conditions may be the only water available. Draining also takes time: a large farm dam or mining water storage may take weeks to drain naturally. And the dam is out of service throughout the repair and refill period, which may extend across an entire season.

GRT: DamSealer — How Polymer Dam Sealing Works

GRT: DamSealer is a specifically formulated complex matrix of soluble and insoluble polymers designed to find and seal leaks in water storage, tailings and environmental dams. The product works with the physics of the leak, not against it.

Self-targeting mechanism. DamSealer is applied to the water surface. The polymer particles sink and are drawn by the currents created by the leaks themselves. Water flowing through a crack, a porous zone or a construction interface creates a localised current that pulls the polymer particles towards the leak path. The product follows the water to the problem — it does not require the operator to know the precise location of every leak.

Progressive sealing. As the polymer particles reach the leak path, they accumulate in the cracks, pores and channels through which the water is escaping. The hydrostatic pressure of the water in the dam assists in holding the polymer in place, pressing it into the leak path and compressing it against the embankment material. The seal builds progressively as more polymer accumulates at each leak point.

Long-term stability. DamSealer has been designed and manufactured to remain stable in the soil profile, providing a long-term solution. Once in place, the polymer becomes part of the dam’s structure, resisting the hydraulic pressures that originally drove the seepage. The seal does not dissolve, degrade or wash out under normal operating conditions.

New dam integration. Although primarily designed for repairing existing dams, DamSealer can also be integrated into the design of new dams where high-quality construction materials are difficult or costly to source. In remote mining locations where the locally available fill material is marginal in quality, DamSealer incorporated during or after construction provides an additional sealing layer that compensates for the material’s limitations.

No draining required. The dam does not need to be emptied. The product is applied to the water surface while the dam is full or partially full. The existing water provides the hydrostatic pressure that drives the sealing process and holds the polymer in place. The dam remains in service throughout the treatment.

Applications: Mining and Agriculture

DamSealer applications across mining and agriculture

Mining Water Storage: Why Every Litre Matters

Mining operations in water-scarce regions — the Pilbara, Goldfields, inland Queensland, South Australia — operate under strict water allocation licences. Every litre of process water that seeps through a dam wall is a litre that must be replaced from bore fields, surface water or purchased supply. In regions where water costs $5–15 per kilolitre delivered, a dam losing 50 kL per day through seepage is losing $90,000–$275,000 per year in water value alone — before the environmental and regulatory consequences of the seepage are counted.

For mines operating under EA conditions that prescribe zero release of contaminated water, seepage from a process water dam or sediment retention dam is not just a water loss. It is a potential non-compliance event. The seepage may carry contaminants — elevated metals, low pH, suspended solids — into the surrounding groundwater or surface water. DamSealer applied to the leaking dam reduces the seepage, protects the water supply and addresses the compliance risk simultaneously.

For tailings dam embankments, seepage is an ANCOLD and GISTM safety concern. Seepage through the embankment increases pore water pressures, reduces the effective stress and lowers the factor of safety against structural failure. While DamSealer does not replace the geotechnical engineering required for tailings dam safety, it can supplement the seepage control system by reducing the permeability of the upstream face — addressing seepage at the source rather than managing it through downstream drainage.

Article 54 covers tailings dam dust and GISTM compliance. Article 51 covers ground and slope stabilisation.

Agricultural Dams: A Simpler Problem, the Same Solution

Farm dams are simpler structures than mining dams, but they leak for the same fundamental reasons: inadequate clay, poor compaction, dispersive soils, cracking, tree roots and animal burrows. The consequences are equally real for the farmer: a dam that cannot hold water through a dry summer means emergency water carting at $500–$1,500 per load, stressed or relocated livestock, failed irrigation, and the constant anxiety of watching the water level drop.

The traditional repair options for a leaking farm dam are expensive, disruptive and unreliable. Draining and recompacting costs $5,000–$30,000 depending on dam size and access. Bentonite blankets require draining the dam, spreading the bentonite, incorporating it into the floor and walls, and refilling — a process that may not work if the bentonite cannot be adequately mixed into the existing material. Importing clay requires a source of suitable material, truck access to the dam and earthmoving equipment on site.

DamSealer provides farm dam owners with an alternative that does not require draining, does not require heavy equipment and does not require identifying the precise location of every leak. The product is applied to the water surface by hand (broadcasting the polymer across the surface) or from a small boat. The polymer sinks, follows the seepage currents to the leak paths, and seals them progressively. If the operator knows where the dam is leaking, a higher concentration can be applied to that area. If the location is unknown, the product finds it.

The application is within the capability of any farm owner. No specialist training, no heavy equipment, no contractor is required for standard applications. The cost is a fraction of conventional repair methods.

The Complete Dam Management System

DamSealer addresses seepage through the dam structure. GRT’s broader product range addresses every other aspect of dam maintenance and environmental management:

GRT9000 — for dams constructed from or founded on dispersive soils. GRT9000 treats the dispersive clay to reduce its sensitivity to water, preventing the tunnel erosion that is the most dangerous failure mode in dispersive embankments.

GRT: Enviro-Binder — for erosion protection on dam embankment slopes. Rainfall erosion of the outer embankment face undermines the dam wall over time. Enviro-Binder binds the surface, prevents erosion and supports vegetation establishment for long-term slope stability.

GRT: CC + Liquid-Floc + Floc Blocs — for treatment of dam water before controlled discharge. Sediment dams and environmental dams that must be dewatered to restore capacity require water treatment to meet discharge quality limits.

GRT: Soil-Loc — for wind erosion protection on dam surrounds, spillway areas and cleared land adjacent to the dam wall.

A Leaking Dam Is Losing More Than Water. It Is Losing Time, Money and Resilience.

Every day a dam leaks is a day the water level drops, the water supply diminishes and the operation’s resilience to drought, production demand and regulatory scrutiny weakens. For a mine, it is process water that must be replaced at cost. For a farmer, it is the water that stands between a productive season and an emergency.

The polymer technology to seal the dam — without draining it, without earthmoving equipment, without the failure modes that make conventional repairs unreliable — is available and proven. GRT: DamSealer follows the leak, finds the problem, seals the crack and becomes part of the dam’s structure. The hydrostatic pressure that was driving the water out now holds the polymer in.

For mine water managers, dam engineers and farm managers watching water seep through a wall that was supposed to hold it, the repair does not require draining the dam, mobilising an excavator or hoping that the same material will perform better the second time. The polymer finds the leak. The physics holds the seal. And the dam holds the water.

Sources and References

GRT: GRT: DamSealer — polymer dam sealing for tailings and water storage dams

Big Ditch Aquatecture: Dam Sealing With Bentonite & Clay (April 2026) — diagnosis-first approach, repair methods, warning signs, NSW/QLD/VIC

Big Ditch Aquatecture: Farm Dam Seepage Control: Techniques & Best Practices (June 2025) — construction materials, geological conditions, control measures

ScienceDirect / Pisaniello: Farm Dams and Integrated Water Storage Safety (2024) — 100+ hazardous SA farm dams, majority unacceptable, 15-year owner inaction, ANCOLD criteria

ANCOLD: The Role of Dams — tailings management, dam safety guidelines, inspection regimes

International Water Power: Safety Management of Dams — The Australian Practice — ANCOLD 2003 guidelines, dam safety programmes, prioritisation

QLD Resources: Dam Safety Management Guideline — referable dams, ANCOLD consistency, inspection levels, state legislative requirements

Tailings.info: Water Management Considerations for Conventional Storage — water balance, seepage losses, decant management, embankment barriers

GRT: GRT9000 — dispersive soil stabilisation

GRT: GRT: Enviro-Binder — embankment erosion control

GRT: Sediment Control Solutions — CC, Liquid-Floc, Floc Blocs

GRT: Dust Suppression Solutions — Soil-Loc

GRT: Dispersive Sodic Soil Stabilisation

GRT: Tailings Dam Dust and GISTM Compliance