This is a tool that is often overlooked.
Many dark energies can not pass over running water.
I felt this for myself one day when at a meeting at a friend's house. The energy in the meeting was so dark and oppressive that I left early. The darkness held until I got out to the sidewalk. Then it just vanished. Poof. Instantly. It stopped me in my tracks. Was it the distance from the house? I stepped back into the yard with one foot to see what would happen. There it was. Right there. Nasty stuff. I stepped back closer to the street and it lifted.
In the weeks ahead, I did some research. Turns out that others have noticed this too. Running water is often a strong deterrent to negative energies. It has to be running though.
The next time I was in the area, I stopped by to see if running water was a factor. Sure enough the water main for the street ran right under the sidewalk in the exact spot where I noticed the darkness lift.
That wasn't the only time that happened.
While shopping with a friend, the energy in the mall turned suddenly dark. Big dark. Instant headache and fatigue. Both of us. So we left. On the walk home, suddenly the dark energy vanished. I asked my friend if she felt the same thing. Yes. Was this a water pipe under the sidewalk? I told her what I'd discovered before. We backtracked to the place where the energy lifted. Sure enough we had just stepped over an underground water line.