If you're handy drain your hot water heater take out the old valve and replace it with a ball valve. You'll need a couple 3/4 in fittings and a short piece of copper pipe. Sweat it together and enjoy.
If you don't like the old tire look after a few years have fun carting that 75 cu.ft. of shit away. At least peat moss or wood mulch will disappear over time . I prefer peat moss.