<p>Two important things come to mind which have been proven successful already, but the problem is much worse due to global warming and climate change.</p><p>First thing to fight is the continued deforestation. Forests, and trees, play a vital role in the control of water flows and floods. This also includes land erosion, or rather quality of ground erosion, as for example happens in currently in Argentina due to the massive shift to Soy farming, without crops rotation.</p><p>Another important, and s far in many places rather successful, approach is giving rivers natural banking again and create natural flood plains. The Dutch call this “room for the river”, which literally means that rivers are given space to flood. Rather than trying to fight the floods, they’ve switched to “living with the water” and embankments (most often natural ones) are placed further from the river’s actual flow, thus creating new and larger floodplains.</p><p>This approach has in recent years also found common adoption in the UK.</p><p>Recommended reading:</p><p>1. Room for the river: https://www.ruimtevoorderivier.nl/english/</p><p>2. Flood walls and embankments (UK Environment Agency PDF): http://evidence.environment-agency.gov.uk/FCERM/Libraries/Fluvial_Documents/Fluvial_Design_Guide_-_Chapter_9.sflb.ashx</p>