Help!!!

[B.O.B.]

I disovered a huge Problem: In my new map, i raised the cliffs to make a waterfall and the smoothened the sides to have a walkable mountain. Now i decided to use none of Blizzard's cliffs and to design my own. But when i now lower the terrain, to create a river, there is no water, where the mountain was before. Can anyone tell me, why and what to do against this?
I really need help!

 

[Dvoth]

Can you add some screenshots?

 

[chenlimin]

lowering the terrain won't make it shallow or deep water, select the deep/shallow water tool.

 

[B.O.B.]

Surely: View attachment Problemfall Wasser.tga
Hope, it helps you to help

{EDIT}
And @ chenlimin: Yes, by using the water tool over the whole map i can reset the water level, but i'd like to keep some regions of my terrain and not to create it all once more.