Dry Climate and Water works

I live in a relatively dry climate.  Annual droughts- often extending for very long periods of time ranging from months to even years.  Aside from water catching off the roof of our home & 'swales' in the property, what is the most important water-works project you would recommend for an area under 1/2-acre?

Rain harvesting basins.  






https://www.harvestingrainwater.com/

Wind breaks and afternoon or filtered shade.  It's not a technically a water work, but it mahes a world of difference.

The answer may be "all of the above", with me adding mulch to the other suggestions.