A big effect of climate change is unpredictable rainfall, causing both droughts and floods. This is an acute threat to crops and livelihoods. Adapt by improving how you collect and store water on your land. Slow it down and harvest it with ponds, tanks, wetlands, swales and trees.
Freshwater is essential for all forms of life on land. Not only does it provide drinking water and help to maintain a thriving ecosystem, it's also vital to agriculture (which accounts for 70 per cent of global freshwater use) and industry (20 per cent), as well as a wide range of household, recreational and environmental activities.
Designing for drought
- Save surplus to get you through bad times. Stockpile surplus water, food, seeds, or money.
- Store water from all precipitation and surface flows in ponds, tanks and wetlands. Swales, ditches, hedges and mulched areas built along contours will hold moisture on site.
- Reduce irrigation using pumped up groundwater. Pumping deep groundwater can deplete aquifers and degrade water resources.
- Reduce crops requiring frequent irrigation. Water intensive crops are being grown in places that do not have the long term water resources to support those crops.
- Reduce soil erosion and build soil health. The healthier and deeper the soil, the more water it can hold.
- Reduce bare soil surfaces. Soil that is exposed to the sun, wind, and falling raindrops is more prone to erosion and dehydration.
- Cultivate tree products. Perennials are more resilient to yearly fluctuations of water availability because of their established root systems.
Designing for torrential rain
- Harvest water as it passes through the site in ponds, tanks and marshy areas.
- Water flow within ploughed fields should be channelized so flood flow does not spread out within fields and damage crops and soils.
- Outside of ploughed fields, the passage of water should be slowed as much as possible through the building of permeable dams, meanders, overflow ponds and the creation of marshes, flood meadows and wooded areas.
- Man-made channels will help direct water. Swales, ditches and mulched areas built along contours will catch and hold water safely, while ditches running down the slope will carry it to a stream or storage area.
- Field drains should be mapped, cleaned and improved.
- Plantings of trees will slow water flow, take up excess water, catch washed away nutrients, and stabilise soil against erosion.
Watershed level planning
True resilience does not happen within the boundaries of one site. It happens by planning at the scale of communities and regions. Water harvesting structures need to be interlinked between farms and villages, and there needs to be a recognition that upstream is intimately linked to downstream. The perspective that needs to be adopted is water resource development at the watershed scale. Another important aspect of restoring the hydrologic cycle and stabilizing the climate is reforestation.
This page is based on text written by Chris Warburton Brown of the Permaculture Association (Britain) for https://www.52climateactions.com, and was created as part of our collaborative GROW Observatory project.
The GROW Observatory has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 690199.