Lost cost, high reward. Not sexy enough to get the attention it deserves.
This year was bad in terms of drought, yet it seems it wasn't as bad as the one we had a few years ago (2018 or 19? I don't remember exactly) because they allowed the water table to go higher a bit, used the ijsselmeer as a giant fresh water reservoir, closed / limited locks, etc. After this year and the rapidly accellerating / worsening effects of climate change, like the drying out (ok, low water levels) of the Rhine, I'm sure they're working hard to do more. They can for example choose to allow the flood plains to flood even when there's no flooding, to (locally) add to the ground water. Granted, it takes (iirc) decades or hundreds of years for that to end up in the aquifers but better now than never.
Other projects I've heard of involve allowing rivers and streams to meander again, undoing the work of straightening them to get rid of water faster and / or optimize shipping traffic.
Los Angeles seems to be waking up to the issue: https://www.ladwp.com/who-we-are/water-system/sources-supply...