Groundwater and Surface water in a Watershed Human Activity
What is Groundwater? • Groundwater is water that comes from the ground. Sounds easy, doesn't it? Amazingly, many people use groundwater but don't even know it. In fact, half of everyone in the United States drinks groundwater everyday! Groundwater is even used to irrigatecrops which grow food for tonight's dinner.
Where Does Groundwater Come From? • Groundwater comes from rain, snow, sleet, and hail that soaks into the ground. The water moves down into the ground because of gravity, passing between particles of soil, sand, gravel, or rock until it reaches a depth where the ground is filled, or saturated, with water. The area that is filled with water is called the saturated zone and the top of this zone is called the water table. Makes sense, doesn't it? The top of the water is a table! The water table may be very near the ground's surface or it may be hundreds of feet below.
Do YOU Live on a Watershed? • Do ya? Huh? Do ya??? • What do you think of when you hear the term “watershed”?
What is a Watershed? • Watershed- the land area from which surface runoff drains into a stream channel, lake, reservoir, or other body of water; also called a drainage basin.A BASIN is the entire geographical area drained by a major river and its intersecting streams. • In every watershed, small streams flow into larger streams, which flow into rivers, lakes, and bays. The smallest streams at the outer limits of a watershed are called headwaters. Headwaters are the source and upper part of a stream.
What is a Watershed? • These headwater streams have no tributaries and are called first order streams. All other streams have tributaries. Second order streams form when first order streams meet.A tributary is a stream that flows into a larger stream or other body of water.
Do WE Live on a Watershed? • All land is a part of some watershed! Not only do streams and rivers flow to a collecting basin, but so too do the impacts that humans have upon those waterbodies. Human activities that impact the quality of the river water flowing into a basin also impact the basin itself.
YOUR Watershed! • http://cfpub.epa.gov/surf/huc.cfm?huc_code=12100304 This is your watershed.
Think About This: • Think about this: have you ever dug a hole in sand next to an ocean or lake? What happens? As you're digging, you eventually reach water, right? That water is groundwater. The water in lakes, rivers, or oceans is called surface water...it's on the surface. Groundwater and surface water sometimes trade places. Groundwater can move through the ground and into a lake or stream. Water in a lake can soak down into the ground and become groundwater.
Where is Groundwater Stored? • Groundwater is stored in the ground in materials like gravel or sand. It's kind of like the earth is a big sponge holding all that water. Water can also move through rock formations like sandstone or through cracks in rocks.An area that holds a lot of water, which can be pumped up with a well, is called an aquifer. Wells pump groundwater from the aquifer and then pipes deliver the water to cities, houses in the country, or to crops.
How Does Groundwater Fit in the Water Cycle? • The water cycle is also known as the hydrologic cycle- the same water is cycled on earth since the beginning of time. • Where does this water come from?
How does the water cycle all begin? • The water cycle has no beginning or ending point. • The Sun plays a major role in the water cycle. • The Sun drives the water cycle.
Steps of the water cycle: • 1) Evaporation- happens when heat is added to water molecules and causes them to slowly transform from liquid into vapor. • What phase change occurs? • 2) Condensation- water vapor travels up into the atmosphere and condenses, forming clouds. • 3) Precipitation- Water vapor in the clouds condense more and more until they form water droplets. The clouds get heavy and cause the droplets to fall as rain, sleet, snow, or hail.
Steps of the water cycle: • 4) Infiltration/Runoff- Infiltration means water soaks into the ground (called recharge). Runoff is when water flows from high points of ground to low points, due to gravity. • Down, down, down the water goes through the soil until it becomes groundwater and is stored in the aquiferbelow.Once the water has joined the aquifer, it doesn’t stop there. The groundwater slowly moves through the spaces and cracks between the soil particles on its journey to lower elevations. This movement of water underground is called groundwater flow.Eventually, after years of underground movement, the groundwater comes to a discharge area where it enters a lake or stream. There, the water will once again be evaporated and begin the cycle again. Water has been transported through the water cycle for millions of years and will continue this cycle forever. In the water cycle, water is constantly on the move.
Click on this page and listen.. • http://www.epa.gov/safewater/kids/flash/flash_watercycle.html
What Happens to Groundwater? • Most groundwater is clean, but groundwater can become polluted, or contaminated. It can become polluted from leaky underground tanks that store gasoline, leaky landfills, or when people apply too much fertilizer or pesticides on their fields or lawns. When pollutants leak, spill, or are carelessly dumped on the ground they can move through the soil.Because it is deep in the ground, groundwater pollution is generally difficult and expensive to clean up. Sometimes people have to find new places to dig a well because their own became contaminated.
Human Activity • Human activities commonly affect the distribution, quantity, and chemical quality of water resources. • Human activity can include: agriculture, urban development and industry, drainage of low-lying areas, construction of levees, dams, or reservoirs and removal of vegetation from flood plains.
Agriculture • Irrigation removes groundwater or surface water for use on crops then carries it away. • Chemicals, pesticides or fertilizers, are applied to croplands and eventually make their way into watersheds can lead to an overgrowth of algae in water.
Urban Development • Discharge from sewage-treatment plants, industrial facilities, and storm water drains, leaking fluid storage tanks, septic tanks, and landfills can also add to the contamination. • Urbanization changes rain run-off from it’s original path.
Quiz Time Which of the following sets of equipment can be used to analyze the effects of human activity on a watershed? A water testing kit, triple beam balance B water testing kit, hand lens, notebook C water testing kit, beaker, hotplate D hot plate, beaker, graduated cylinder
Discuss this with each other… • A small stream runs through the center of a residential neighborhood. Water enters the stream from a series of storm drains in the area. For many years, the shape of the streambed, the amount of water, and the species of wildlife have remained stable; however, there has been an increase in building in the area. New homes, new streets, and new storm drains have impacted the area. Describe what effect the changes will likely have on the stream.
Palo Duro Canyon, often called the Grand Canyon of Texas, is located in the Panhandle. The steep walls and deep caves of the canyon were most likely carved by— • A years of prevailing winds from the Rocky Mountains • B deforestation by early settlers • C water erosion from a fork of the Red River • D continuous, intense rainfall over long periods of time
Finally you’re finished! Hope you got all this great information on watersheds and the water cycle.