What are the consequences of overdrawal of water?​

As the water table goes low, water may not be easily obtained leading to it scarcity. Overdrawal of water can also lead to sinking or lowering of the land surface that can make it prone to flooding. Streams and water bodies may also get disconnected due to over-withdrawal of water.

it's diluted or concentrated

in a diluted solution, you can add a lot more solute but in concentrated only a little more can be added