The way the Dutch build everything water related is genius.
Field, ditch, elevated bank, line of trees, road, ditch, field = continual drainage, strong containment, trees dry the ditch and road, roads almost always passable.
Fields below town level, possible to controlled flood huge areas, but to a shallow depth – town stays dry
Roads and most towns paved/metalled with interlocking brickwork – maximum local drainage. Bricks delivered on pallets, and placed by a giant grabbing arm, 100 at a time.
That’s before even mentioning the rivers, the cleaning/cutting-back of the plant growth, the big sea dijks etc etc…