As I expected, my water heater finally sprung a leak. The water heater was here when I bought my home almost 25 years ago, and it looked old then. The plumber who put in the new one said he had only ever seen two other water heaters this old, and thought it might even be original to the house, i.e. installed in 1965. I have been expecting it to fail for 25 years. It finally did.