4. Agricultural Uses of Water Irrigation A majority if agricultural water is for irrigation of crops Large number of crops require long growing seasons, but lots of rain In US, the areas that have long growing seasons are quite dry California and Texas Irrigation water is typically supplied by aquifers or lakes/ponds One third of all marketable agriculture crops are irrigated at some point. 14% of all agricultural land is irrigated at some point Quality for irrigation water is considerably less that for other purposes.
5. Agricultural Uses of Water Livestock Usually from ponds or pumped to livestock tanks Needs to be higher quality Dilution for Pesticide Application Lower quality is ok
6. Industrial Uses of Water Processing Consumptive Used in manufacturing – i.e. juices, canned goods, sodas Needs to be highest quality Non-Consumptive Returned to the water cycle mostly unchanged Cooling Used to cool things like metals, condensing distillates, and nuclear reactions Thermal Pollution – returns water at a much higher temp Bad for aquatic life
7. Domestic Uses of water Amount of water used is variable depending on the development of the country If water is withdrawn manually – consumption is much less If water is mechanically withdrawn – consumption is much more If water is scarce – it is hoarded If water is plentiful – it is wasted Cooking, drinking Bathing, toilets Watering gardens, lawns Water fountains, pools
8. Domestic Uses of Water Much of the water used in the US is returned to the water supply as wastewater (sewage) Showers, toilets, sinks, storm drains, etc. Must be treated with complex processes and systems before it can be reused Sewage treatment plants are large and expensive
9. Water usage Each day 330 billion gallons of water are withdrawn from our freshwater reserves. 26 billion for households 304 billion for industrial and agricultural The average American uses 90 gallons per person per day. Must be of the highest quality Most of these 90 gallons are returned to the water supply as waste water
10. How much water do we use? Total freshwater withdraw in Million acre-feet
11. Freshwater Withdraws A acre foot is how much water it would take to flood one acre of land one foot deep. It takes 325,828 gallons of water to flood an acre of land one foot deep. One million acre-foot is equal to 325,828,000,000 gallons or over 325 billion gallons. So to use 172.3 million acre feet for irrigation means that we use nearly 56 trillion gallons of water. On average the US withdraws over 111.5 trillion gallons of water from our freshwater supplies each year.
12. Where does the water come from? Surface water Ponds, lakes, rivers, etc Ground water Underground lakes, rivers, etc. Aquifers Porous rock that acts like a sponge and holds water Vast underground networks
13. How much water do we have? 97% of the worlds water is in the oceans and seas 3% is fresh water that could be consumed 77% of the worlds fresh water is tied up in the polar ice caps and glaciers So only .69% of the water on earth is actually consumable
14. Why do we need water so badly? Water is essential for all life forms as a crucial ingredient in cell makeup, digestion, etc. 65-70% of the human body is made up of water In order for cells to take up water it must be pure. Every year 900 deaths in the us are due to waterborne infections Bacteria, viruses, protozoa
15. Why does water have a cost? In the US most (85%) Americans get their water from a public works. Pay a monthly bill based on gallons of water consumed. Payment is used to pay for labor to treat sewage maintenance of lines Chemical additives Monitoring of safety of water Regulated by federal law
16. Why does water have a cost? Other 15% get water from a private well Must dig well and pay for electricity to pump water Must monitor own quality Often a cost in treating water to make it fit for consumption Filters, softeners, etc.
17. Water Cycle The continuous movement of water from the earth to the atmosphere and back to the earth. The sun provides the energy for the water cycle, also known as the hydrologic cycle. The water cycle occurs in four overlapping spheres.
20. Hydrosphere Water moves from the earth to the atmosphere through the processes of evaporation and transpiration. Evaporation is the transformation of water from its liquid form to its gaseous form as a result of coming in contact with heat or the air. Transpiration is the process of plants releasing water through their leaves is called.
21. Atmosphere Air that holds moisture until it falls as precipitation. Precipitation is the moisture from the atmosphere that is returned to the earth in the form of snow or rain.
24. Physical and Chemical Makeup of Water Water, in its purest form, is tasteless, odorless, and colorless. It is a chemical compound made up of two atoms of hydrogen and one atom of oxygen. Its chemical symbol is H2O.
25. Physical States of Water Solid form of water is called ice. Water freezes at 32F or 0C. Gaseous form of water is called water vapor or steam. When water boils it turns into water vapor or steam. Water boils at 212°F or 100°C. In between the gaseous and solid form, water is in its liquid form.
26. Chemical Make-up of Water Water that contains salt is called saline water. Sodium chloride, potassium, and magnesium can raise the level of salts in the water. The amount of salt in the water will determine its usefulness. Water that is too high in salt cannot be used for drinking or irrigation.
28. Freshwater Water with less than 3.0 parts per thousand (ppt) of salt. Most commonly found in drilled wells, streams, and lakes.
29. Saltwater Water with 16.5 ppt or more of salt. Some ocean and sea water is as high as 33 to 37 ppt. Saltwater makes up about 97 percent of the earth’s water.
30. Brackish Water A mixture of saltwater and freshwater. Brackish water is found where freshwater flows into the ocean or other bodies of saltwater. An estuary is the area where a freshwater stream flows into the ocean or a saltwater lake.
31. Usable Water Two main ways that salt water and contaminated water can be turned into usable water: distillation and desalination.
32. Usable Water Desalination is the removal of salt from water. It can involve the process of distillation or reverse osmosis but is not economical on a large scale. Reverse osmosis is like using a microscopic filter that “presses” the clean water molecules through and leaves the salts behind. Distillation is the boiling of water and collection of its vapor. The vapor then turns into liquid when cooled. The liquid is pure at this point.
33. Flowing Bodies of Water One of the most important parts of the water cycle is the stream. Streams are flowing bodies of water that are useful resources for irrigation, factories, and local water systems.
34. Types of Streams Stream type is determined by the volume and velocity of the movement of water, or streamflow. The four types of streams are rivers, creeks, brooks, and canals.
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36. Creek A stream that is smaller than a river. Often flow into rivers, lakes, and oceans.
37. Brook A small stream. Often flow into creeks, rivers, lakes, and oceans.
38. Canal An artificial waterway built for transportation, to relieve flooding, or to divert the flow of water.
39. Stream Hydrology The study of flowing water and its environment. The physical, chemical, and biological properties of the water and the surrounding environment are tested. The ecosystems, including food webs, are studied.
40. Stream Structure The area through which water flows in a stream is called a channel. A channel is usually formed with rock or soil and it is the sides and bottom of the stream. The bottom of the channel is called the stream bed, the sides are called the stream banks.
41. Stream Structure When a channel is not large enough to hold the flow of water the area that overflows is called a flood plain.
42. Non-Flowing Bodies These bodies may be natural or artificial. Non-flowing bodies of water influence the weather and climate of an area. Commerce, food supply, and recreational activities can also be influenced by the non-flowing bodies of water in an area.
43. Types of Non-Flowing Bodies Seven types of non-flowing bodies of water are oceans, lakes, ponds, reservoirs, sloughs, marshes, and estuaries. As in flowing streams, non-flowing bodies of water may contain a variety of ecosystems.
44. Oceans Large bodies of saltwater. Cover almost 75 percent of the surface of the earth.
45. Lakes Bodies of freshwater that are surrounded by land. Vary in size, some are natural and others are man-made.
46. Ponds Non-flowing bodies of water that are smaller than lakes. Commonly manmade and used as a source of recreation or for use by livestock.
