Short answer: Dam construction faces a range of serious challenges including variable soil conditions, wet weather delays, managing groundwater during construction, achieving correct compaction, and designing effective spillways. Big Ditch Aquatecture tackles these challenges through experienced project management, the right equipment for each site, and decades of hands-on knowledge building dams across diverse Australian landscapes. Anticipating and solving problems before they become costly is the hallmark of an experienced dam builder.
Quick Answer: The biggest challenges in dam construction are sourcing and placing good clay, managing water during earthworks, designing a spillway that handles extreme rainfall events, and building on difficult ground — dispersive soils, fractured rock, or steep topography. Every site throws something different at you.
Big wind. Big challenges. Big wall. Big dam. Dungog NSW February 2019
Check more here
Key Takeaways
- Sourcing non-dispersive clay close to the dam site is the most common constraint — carting clay long distances drives up costs fast
- Water management during construction (diverting natural flows, managing rainfall runoff) prevents washouts and costly delays
- Spillway design for extreme flood events is a safety non-negotiable — undersized spillways cause wall failures in large storms
- Dispersive soils require lime treatment or full replacement before being used in the dam wall core
- Steep or rocky sites add complexity to batter design and may require specialist engineering input
Frequently Asked Questions
What is the hardest part of building a farm dam?
Most often it’s the clay — finding enough non-dispersive, high-plasticity clay close enough to the site to be economical. When you have to cart clay long distances, costs climb fast.
What causes a dam wall to fail?
The main causes are overtopping (spillway too small for a major flood), internal erosion through dispersive or poorly compacted clay, animal burrows, tree roots, and piping from inadequate outlet structures.
How long does dam construction take?
A standard farm dam takes 1–3 weeks of machine time depending on size. Large or complex sites can take longer. Site access, weather, and clay availability are the main variables.
Do dams require ongoing inspections?
Yes. An annual visual inspection and a professional inspection every 5–10 years (or after major flood events) is good practice. For large dams, state regulations may mandate formal safety reviews.
Need help with your own dam? Book a site inspection with Big Ditch — we build and repair dams across NSW, Queensland, and Victoria.