Mt Shuksan in the North Cascades, WA. Beautiful hike on Chain Lakes trail.

Yes, I was afraid of that, thanks Andy. I think I'm going to try a combination of rope and pool noodles :grin:

Lisa,
In my experience, just releasing a bit of hot water from the tank is enough to clean off the valve seat. Simply lift the lever a bit (it is spring-loaded), and let out some water. It's hot, so be careful. For safety's sake, turn off the electric heater element while you do this, to be sure the element doesn't get exposed if the tank level got too low. The dripping should clear up right away, but if not, try it one more time. If that doesn't work, it may be time for another pressure-temperature valve.

String Lake Grand Teton N.P. Our summer volunteer position.

Excellent, thanks Ray. I feel much better knowing it's not an urgent repair.

It's the water heaters expansion valve. They do drip from time to time but if it gets to be excessive then they can be replaced.