There are a trifecta of water-saving opportunities in the bathroom. By installing a low-flow showerhead, a low-flow faucet aerator and a dual-flush toilet, you'll save thousands of gallons of water each year.

The first two are easy DIY jobs—learn how to install a low-flow faucet—and a toilet can be done with a little homework. To really go for the gusto and go for a water-free toilet, check out composting toilets.