Make the rainwater slow:
This is the principle: Make the rainwater slow when it runs down the mountains and hills. In this way, there is enough time for it to infiltrate the ground and replenish the groundwater reservoirs. This method is ancient and a proven tradition that you surely know. You can create terraces (on which you can also grow plants), small walls and ditches, holes in the ground.
Help nature and make the soil better:
Scientific studies have shown: The soil in the Asterousia region is eroded, desertification (the landscape becoming a desert) is spreading increasingly. Various factors have led to an extreme decline in plant diversity. This way, good planting soil is washed away and rainwater doesn‘t infiltrate. However, these areas can be easily revived. All you need is different plants that support each other. Then nature does its work on its own. There are also certain types of trees which can be planted everywhere. They provide shade for the other plants and also loosen the soil up even in the deeper layers. All of this has the effect that rainwater can seep in again and fill up the groundwater reserves.
Before and after: An example for plant diversity and reforestation from otherwise in Greece
Industrial hemp production:
It is a magic plant: Industrial hemp. It has nothing to do with the basic plant for the drug, but is a relative without an intoxicating effect. The advantages are impressive: little effort, little water required, easy harvesting, versatile use and extremely good for the soil. It can be used for products like clothing, accessories, health and wellness, ropes, furniture and much more. Since 2019 it has been allowed to use it in agriculture in Greece.
Another example for slowing water during rain season: