I'm on a diet, please don't put words into my mouth. There are months that we have too little rain, but we're far from continuous drought conditions. We're still getting 50+ liters/sqm per month.
The surface water strongly affects farms and forests, but we won't change that by using less ground water (unless the hope is to have the ground water climb to -1m everywhere, at which point we're living in a bog). Additionally, rising ground water might have nasty side effects for plants, as salt in the earth will also be transported up.
Surface water retention is about management, not about offsetting that with savings. We do get plenty of surface water, but much of it will be "wasted" because it'll cause floods. Aggressive diking and straightening of rivers does play a part there, and we'll be wise to adapt to changing weather patterns and climate.