The increased human population has increased our need for freshwater, and we use over four times as much freshwater as we did only fifty years ago. Since only 1% of the water on our planet is fresh water, this is a limited natural resource. Some things we can do to conserve freshwater are taking shorter showers, turning off the water when you are washing your hands or brushing your teeth. Scientists and engineers have developed ways to turn saltwater into freshwater, but it is expensive and requires a lot of energy. More innovations in science and engineering may be able to help solve this problem in the future.