Marshal Dughan wants you to speak with Guard Thomas.
If you are concerned that the rumors of murlocs are true, then do this -- travel to the eastern Elwynn bridge and speak with Guard Thomas. He has been stationed at the bridge for the past week and will know the state of the area.
Bring me his report.
Yes, murlocs have settled in and around the streams of eastern Elwynn. We don't know why they are here, but they are aggressive and at least semi-intelligent.