steve's barking water runs down hill

Water runs down hill, what does that mean?
Water seeks in own level, what does that mean?
Why are we building up instead of letting the water flow down?

I may not be a scientist but I do remember from some old classes that I took that water flows down. Now what I've been thinking about is there are certain places in this wold were it might be a better idea to build ditches that would open up just before flooding happens. The ditches would lead into large tubing that would hold the water.
Our farm land every few years get flooded, suppose we were to build build reservoirs under our farms so during droughts we could pump the water up to water our crops.
Lets take a city like New York, wouldn't it be better to have the water from the ocean and the flooding of the rivers go under the trains the electrical and communication wiring, and under the tunnels from water of the reservoirs. The water could be used for energy (the hydrogen) and some desalted for drinking.


Of cause the negative would be the collecting of water underground possibly would bring environmental havoc.
There wouldn't be enough water evaporating. Less cloud covering, thus heating up the earth Less evaporation less rain, thus less water in places that may need them with out rain from the evaporated water. ( Of cause a new industry might pop up, the transferring of water).

There tends to be a negative and positive to all things.