Chapter One Chapter One The lower Fraser River near its mouth seen from an airplane ROWENA RAE My Watery World I grew up in Vancouver BC a city with lots of natural beauty snowcapped mountains beaches forests and the Fraser River This river drains such a large area of land that the entire country of Romania could fit inside its watershed I’ve been lucky to see many parts of this long river from its clear chattering headwaters 870 miles 1,400 kilometers inland to its wide swiftly moving middle to its many-fingered delta and milky-brown exit to the sea One of my favorite views of the Fraser River is from on high I’m reminded of the river’s grandeur and also of the many ways that people affect it by building and farming nearby navigating boats and changing the look of the shoreline A Watery World Beginning with Basics Beginning with Basics What are the two most basic things people need to survive Water to drink and food to eat Where do water and food come from I mean before they get to your kitchen tap and refrigerator Water comes from lakes rivers and streams and from precipitation rain snow and fog Food also comes from lakes rivers and streams as well as from the ocean and the land Together water and land make up watersheds The water part of the word watershed is obvious The shed part comes from an Old English word meaning to divide or separate It refers to a high point of land where a river starts its headwaters or source At this point the hills and mountains form a ridge that guides precipitation in a certain direction as it begins to tumble downhill All the water falling on one side of the ridge goes one way and all the water falling on the other side goes the other way The watershed is all the land on one side of the ridge plus all the water in and on that land Think of the land as a bowl or basin catching the falling or melting precipitation so another term for a watershed is catchment basin
The Mississippi watershed is the largest catchment basin in North America This aerial view shows the Mississippi River in dark blue and the smaller rivers and streams that all eventually flow into it The watershed drains south into the Gulf of Mexico HORACE MITCHELL NASA GSFC No matter where you are on the land whether on a beach at the edge of the sea or in a forest of trees smack in the middle of a continent you’re in a watershed And no matter where you live on a farm with miles between you and the neighboring farm or in an apartment on the busiest street of the biggest city you’re in a watershed Even if you live on an island as I do you’re in a watershed In watersheds the connections between water and land flow deep excuse the pun And these connections are critical for ecosystems and all the plants and animals that live in them including people Nomads by Nature Nomads by Nature Humans have been around for millions of years Our species Homo sapiens began walking on Earth around 300,000 years ago All early humans lived off the land literally They drank from lakes and streams dewdrops on leaves and puddles after rainfall They might have carried a little bit of water with them Early humans often camped near rivers and lakes BRIDGEMAN IMAGES 11 11 Gulf of Mexico
in a folded leaf or an animal skin They followed animal herds learned which were the best fishing spots and paid attention to the seasons and to which plants produced food when The food and water-gathering activities of early humans affected the local environment where they lived If they killed an elk calf to eat that calf wouldn’t grow up to have its own calves If they used fire to cook the meat there would be fewer branches and sticks to decompose in the forest and some air pollution from the burning wood If they slipped and slid down an unstable riverbank to get water some of the soil would fall into the water and smother insect larvae or fish eggs These effects were small and in small areas As human history marched along people started learning how to get more from the land and water They got better and better at manipulating manipulating which means using or changing something in a skillful way their environment to get what they wanted And the more they manipulated their environment the bigger and more wide spread the effects became Farming Frenzy Farming Frenzy People’s relationship to land and water changed when farming began about 10,000 years ago in the Middle East and a bit later in China and the Americas It takes land to grow crops and it takes water to keep seedlings from drying up The perfect place to farm was on land alongside large rivers that flooded their banks every year Not only did this land get a surge of water in every flood season but the water brought sediments fine particles cles of sand soil and clay containing nutrients As floodwaters drained away these sediments often called silt settled onto the land making it very fertile or rich in nutrients The Nile River in Egypt has a particularly large delta The river branches into many fingers that spill into the Mediterranean Sea Some of the earliest agriculture in Water taken straight from a stream or lake needs to be filtered boiled or treated in some other way to make it safe to drink STOCKSTUDIOX GETTY IMAGES LOOK AND LEARN BRIDGEMAN IMAGES Ripples Ripples One of the earliest ways to lift a large amount of water from a stream or lake was to use a long pole with a bucket on one end and a counterweight on the other end The pole was mounted like a seesaw Called a shaduf in Egypt and a denkli in India this device was in use about 5,000 years ago and in some places is still used today 12
Greenery borders the Nile River The river delta at far left opens into the Mediterranean Sea JOHNSON SPACE CENTER NASA Ripples Ripples The oldest known wells are on the island of Cyprus in the eastern Mediterranean Sea They were dug 6 5 feet 2 meters wide and 26 feet 8 meters deep to reach water in the ground These wells were dug at least 10,000 years ago The ancient city of Angkor in today’s Cambodia thrived because its people controlled and stored monsoon rains After the civilization collapsed the jungle took over the buildings SERGEYCHERNOV DREAMSTIME COM the world started in the Nile River’s delta and in nearby Mesopotamia present-day Iraq and Iran where two big rivers the Tigris and the Euphrates flow into the Persian Gulf Relying on floods worked well at least when the floods came For many months of the year there weren’t any flood waters And some years were drier and some were wetter So after several thousand years of farming by the cycles of nature people started making the water go where they wanted it to go This was the beginning of artificial irrigation People dug ditches to direct water to their fields They blocked rivers with dams and weirs to send the water in particular directions They built ponds to keep some water for later use These efforts helped to control the water flowing onto cultivated land to grow crops Putting Down Roots Putting Down Roots What did farming give people Food That seems obvious but there’s more to it As agriculture and irrigation got more efficient efficient food became more abundant People didn’t have to wander over large areas looking for their lunch so they could settle down and stay in a single spot Villages sprang up and some of them got quite big Over time more and more people populated towns and cities that covered large areas of land And because humans need water to survive people developed ingenious ways to tap into sorry another pun nature’s liquid gold Water that is I could write a whole book just about past civilizations and how they prospered by changing the land and manipulating water ways for their own purposes Let me tell you about a few of them
