How+did+canals+help++civilization?

How did canals help the growth of civilization?   Canals help civilization because supplied a surplus,or an extra  supply of food. You will never go hungry again! Other great features include:

 
 * we aren't getting constantly flooded
 * easier to carry water
 * easy way to cultivate and domesticate 
 * during droughts reservoirs are filled with water
 * no more famine
 * and much, much more!!!