How to build resilience against prolonged periods of low rainfall

Water scarcity often arrives long before the ground actually cracks. For many in the agribusiness sector, the crisis begins when the decision to sell livestock or reduce crop acreage becomes a necessity rather than a choice. Waiting for a formal drought declaration from meteorological services often means the most effective window for preventative action has already passed. Effective drought planning is about managing the gap between the water you have and the water your systems require.

Improving soil water holding capacity

The most effective way to manage a drought is to ensure that when rain does fall, it stays in the ground. Soil structure plays a decisive role in this process. Soils that are heavily compacted or lack organic matter allow water to run off the surface rather than infiltrating the root zone.

Increasing organic matter is a long-term strategy that pays dividends during dry spells. Decomposing plant material and manure act like a sponge, holding moisture that would otherwise evaporate or drain away. Cover cropping is another vital tool. Keeping a living root in the ground helps maintain soil structure and prevents the surface from baking into a hard crust. This crust acts as a barrier, causing subsequent light rains to bounce off the surface instead of soaking in.

Mulching is also highly effective for smaller scale operations or high-value horticultural crops. A thick layer of organic mulch reduces the temperature of the soil surface and slows the rate of evaporation. This keeps the root zone cooler and more stable, which is essential when ambient temperatures rise.

Managing water infrastructure and storage

A drought plan is only as good as the physical ability to move and store water. It is easy to overlook the maintenance of tanks, dams, and irrigation lines during wet years, but these are the first points of failure when supplies run low.

Regularly inspecting dams for silt buildup is essential. As silt accumulates, the total volume of water a dam can hold decreases, meaning you have less of a buffer when the rains fail. Similarly, checking irrigation systems for leaks can prevent significant waste. Even a small leak in a main line can result in hundreds of litres of lost water every day.

Calculating your total available water storage against your peak demand is a necessary exercise. This calculation should account for evaporation losses, which increase significantly during hot, windy periods. If the maths shows a deficit, the focus must shift to reducing demand or increasing storage capacity before the dry period begins.

Strategic livestock and crop adjustments

When water becomes a limiting factor, the number of mouths to feed must be addressed. The most difficult part of drought management is deciding which animals to sell or cull. It is often better to reduce herd sizes early, while animals are still in good condition and market prices are stable, rather than waiting until they are stressed and losing weight.

Reducing stocking rates before the worst of the drought hits allows you to maintain higher quality animals on the remaining forage and water. It also reduces the pressure on your pasture, which helps the land recover more quickly once the rain returns.

In cropping, the decision to plant can be a gamble based on long-range forecasts. If the outlook is poor, it may be more profitable to fallow a field or plant a short-season cover crop rather than committing expensive inputs like fertiliser to a crop that may fail. This preserves capital and protects the soil from erosion.

Monitoring and early warning systems

Relying on a single source of information is a risk. Successful managers use a combination of local weather station data, soil moisture probes, and regional agricultural reports. Soil moisture probes provide direct evidence of how much water is actually available to the roots, which is often more useful than looking at rainfall totals alone. A week of heavy rain does not help if the water runs off the surface, whereas a small amount of rain can be highly effective if the soil is prepared to receive it.

It is also important to monitor the condition of forage and pasture. If the growth rate of your primary feed source begins to decline, it is an early indicator that the system is under stress. Using these indicators allows for a staged response, moving from minor adjustments to more significant structural changes as the situation evolves.

Things to try this week

• Calculate the total capacity of your primary water storage and estimate your daily usage during a peak heat period.
• Inspect all irrigation pipes, valves, and tank connections for signs of leaks or slow drips.
• Test the soil moisture at different depths in a field to see how effectively your current soil structure is retaining water.
• Review your livestock numbers and identify which animals would be the first candidates for sale if water supplies drop below a certain level.