Oil or water based stain for old deck


New member
I looked at a 2 level deck last week that's about 15 years old. Never been stained. The wood is salvageable - no sagging and seems strong. Surprisingly, even with the drought we've had around here, my moisture meter says 15-20% on the top deck, and 20+% on the bottom deck. Given the moisture, is a water based stain the better choice?