Almost three-quarters of the Earth's surface is water. Many animals live in our oceans. We need clean drinking water to survive. But water sources all over the world are drying up or being polluted. You can help prevent this. This book contains important information, helpful tips and stories of people who have found ways to save water and keep rivers, lakes and seas clean. There are also lots of fun activities and do-it-yourself projects for you to try at home.