Droughts, Flooding Rains and Climate Change : Climate Smart Farming

Climate Smart Farming

#5 Droughts, Flooding Rains and Climate Change

With the most recent La Nina event during spring and summer 2020/21, cooler than average conditions, flooding and higher than normal rainfall in mid to late 2020 and into 2021, focus has turned from fire and drought, lack of water and extreme heat to managing soggy conditions, waterlogged pastures and flooding.  Conditions now in the far southeast of NSW are very different from the extreme drought which gripped the region over the previous three years.

Our climate is becoming more variable and with more extremes. More intense droughts and rains, stronger winds and worse storms are likely with climate change.  In south-eastern Australia we can expect longer dry periods, and stronger hotter winds punctuated by heavy rainfall events and increased storminess.

Since the late 1990’s, the southeast of Australia has experienced two record breaking droughts and approximately 15-20% less rain compared to the long-term average (of 100+ years). But each of these two extreme droughts have been broken by intense rainfall, associated with a La Nina event.  This heavy rain has fallen on large areas of bare ground, and, in 2020, across badly fire affected catchments. 

Increase in extreme weather is a higher risk to people, agricultural production and natural ecosystems, than more gradual changes in weather. The increase in high temperatures, heatwaves, long dry spells and high winds which we have been experiencing in the far south east is higher risk than the predicted average increases. The risk of heat stress is greater for people and animals; livestock and crop health declines more rapidly; and risk of wildfire grows exponentially.  Similarly, when the rains and storms come, risks of flooding increases and runoff from dried landscapes is more severe. 

In dry periods soil moisture disappears, soils compact and biological activity declines. Vegetation dries out. Pollination of both native plants and food crops is disrupted, and habitat is degraded. The ranges of many plants, insects, birds and other animals reduce. When it finally rains soil is eroded and takes with it nutrients and agrochemicals into waterways to clog wetlands and estuaries and pollute coastal waters. The health of river and coastal systems suffers and soils are permanently lost.

Despite the relief many people now feel from seeing creeks running, dams full and vegetation recovering, when the rains finally fall after drought there is a new set of impacts and risks.  Across the far south east of NSW, many hill slopes and riparian zones have been heavily cleared, the landscape is undulating with sometimes steep slopes, and cattle and sheep graze some riparian zones and wetlands. The heavy rainfalls which broke the 2017-2020 drought carried large amounts of ash and sediment from drought and fire devastated forests, grasslands and bare paddocks downstream into wetlands, estuaries and coastal waters.  Some wetland and estuarine ecosystems were smothered, there was infilling and shallowing of parts of coastal lakes and estuaries and sediments and nutrients surrounded the oyster beds from which oysters are sold across Australia and overseas. Oysters were contaminated and oyster farmers stopped harvesting, losing income and future harvests as larvae and juveniles were also impacted. 

Examples of impacts of more extreme climate on SCPA farms in the far south-east.

By March 2018, when the CSF project team had started working with farmers on reducing the risks from climate change, farmers and growers across southern and eastern Australia were severely challenged by drought by the intensity of the 2017-2020 drought. In the far south-east each farm in the CSF dams were drying out rapidly, soils were very dry, crops were failing, and there was a frequent need to pump water from declining water resources.  Strong and hot winds increased the impacts of drought. 

During 2018 and 2019 the drought worsened. By November 2019 one of the CSF project farms closed their market garden entirely, saving their usually secure water resources for people and animals and to keep perennial trees and vines alive.  Others were destocking, hand feeding remaining livestock and carting water for animals and plants. Grasslands were declining and rotational grazing regimes were difficult to sustain.  One farm with a new venture lost many of their vines and their entire 2019 harvest when their normally permanent creek dried out.  Forests and native woodlands and grasslands, revegetation and orchard trees and harvests were suffering. 

The devastating wildfires then hit the far south-east in December 2019 and January 2020.  Some farms suffered severe fire damage, on others people were evacuated several times. Some farmers, trapped by the unprecedented speed with which fires moved, were forced to shelter in place. Livestock were threatened and moved to emergency refuge areas or, in some cases, lost to fire. 

Rainfall finally extinguished the fires and eventually broke the drought. But the intense rain on the hardened dry ground brought new challenges. On one farm, where creek bank revegetation was not yet well established and where there was little upstream vegetation, most seedlings were lost.   Another farm had considerable downslope soil and silt movement, despite early destocking and swales and berms across contours. Other farms were isolated on several occasions by floodwaters. 

In the subsequent season temperatures remained cooler than usual and there was continuing rainfall.  While some crops grew well and areas of native vegetation started recovering, experienced growers found it harder to judge planting times and predict growth and harvests. There were disruptions to insect life, pollination for some species was less reliable and cooler temperatures slowed growth and germination.

What next? Managing a more extreme climate

Strategies to manage more extreme weather can range from comparatively small-scale adjustments to an existing farming operation, through more comprehensive changes to a farming system, to a set of changes which can make a major transformation to lifestyle and the farm and its operation.

After the recent cascade of extreme events - drought, bushfires and floods – SCPA’s CSF project farmers, along with many farmers across the region, are reviewing their operations.  Some farmers, with access to insurance have recouped losses and begun rebuilding. Others who suffered outbreaks of disease in stressed livestock, have sold their animals and are resting and quarantining pastures before restocking.  Farmers, with help from Landcare and Local Land Services, are revegetating riparian areas and fencing off rivers, creeks and wetlands.  They are experimenting with planting techniques and works to slow flood waters and protect revegetation.

Water security is high on the priority for many farmers. Strategies include:

  • Using water more efficiently: analysis across the world and our experience and observation across the far south- east shows that large water savings can be made on farm and across the region.
  • Retaining water in the landscape and building the soil reservoir, through slowing the way water moves downslope with vegetation, swales and berms, improving soil health, reducing cultivation and keeping soils covered
  • Reusing and recycling water in rural, urban and industrial settings
  • Improving water infrastructure (without reducing supplies for downstream users).  Using covered water sources where available, including large tanks and groundwater, reducing evaporation from dams by increasing wind breaks and shading from sun, encouraging runoff into dams by constructing swales, preventing all leaks in water delivery systems.
  • Changing farming production type and location, if assessment of drought risk indicates this is needed

Farmers are planning infrastructure and housing more able to withstand extreme events and are working on strategies to reduce rain, wind and storm impacts to the landscape, through improving the soil’s water holding capacity and slowing water movements and runoff.  Many are seeking ways to reduce the fire risk to their farms, and some are working with local groups to change burning practices and learn from Indigenous cultural burning regimes. Some farmers are changing crop and livestock species and varieties to those better able to withstand extremes and are working to establish more resilient grasslands and pastures.  Many farmers are, however, still counting their losses and working to recover physically and emotionally from drought and bushfires. Some have retired from farming and some others are considering leaving their properties.  


SCPA wishes to acknowledge and pay our respects to the Traditional Custodians and Elders of this land.