Clear blue water fills the Pingyuan Reservoir, located just outside of Zhaodong City in northeastern China. Water stored here serves the more than 100,000 inhabitants of Zhaodong and surrounding farms of Heilongjiang Province, which grow soybeans, maize, wheat, potatoes, beets and flax. For a sense of scale, the Pingyuan Reservoir covers about 1.32 square miles (3.4 square kilometers) — roughly the same area as Central Park in Manhattan.