Quest:Disturbance at Umbrafen Lake

Objectives
Investigate the cause of the water depletion at Umbrafen Lake. Then return to Ysiel Windsinger at the Cenarion Refuge in Zangarmarsh.
 * Umbrafen Lake Investigated

Description
We came to Outland expecting to find small pockets of life. What we discovered in Zangarmarsh was a lush environment with a thriving ecosystem. Our initial assessment of the area was deceiving, however. The water levels at the lakes and marshes have consistently been going down since we started taking measurements. The impact this could have on the local animal and plant life is disastrous. Go to Umbrafen Lake, southwest of here, and look for clues related to this water depletion.

Reward
You will receive:

Completion
The naga are behind this! But why? From what you describe, that steam pump must be part of the cause for the water levels dropping in the marsh! No matter - this explains their open hostility towards us. Let's not waste any time, I need you to perform another task for us.

Gains
Upon completion of this quest you will gain:
 * 10400 XP (or at level 70)
 * 250 reputation with Cenarion Expedition