Understanding where your water comes from will help you understand what you can do to mitigate the effects of drought. Your water supply might be from surface waters (water on the surface of the earth, like rivers) or from groundwater (water that is under the surface of the earth). Conserving water is the best way for us to make sure that we all have water even when we are in drought. But sometimes, if a drought is very severe or if people don’t use less water, we have to make sure we have enough water. Let’s take a look at some ways to store water and get that stored water to people when it’s needed.
Dams
Many people rely on rain or snow that flows into rivers for their water. When we have a drought, we might not have enough rain or snow to keep enough water in the river for all the people who need the water. To make sure that they have enough water throughout the year, people build dams to store water when they need it.
When a dam is built on a river, a large lake, called a reservoir, is made. The reservoir “stores” the water for people’s use. Reservoirs can provide fish and wildlife habitat and also are often great places for us to boat and fish. They also can be used to produce power.
About 75,000 large dams have been built in the United States, and that number is continuing to grow. However, in some places, dams are being removed from rivers. Dams do help us, but they have some drawbacks. Reservoirs can provide some fish and wildlife habitat, but they can also create problems for the health of the fish and wildlife that live in the river. Dams also wear down over the years and can create safety problems. So, because of some of the drawbacks of dams, people are always looking for new ways to store or protect our water supplies.
Groundwater and Wells
Another source of water is groundwater (water found below the surface of the earth). Aquifers are like underground lakes. Just like lakes above the ground, aquifers can be different sizes. Some are very small and some are very large, like the Ogallala Aquifer. The Ogallala Aquifer is under parts of South Dakota, Nebraska, Kansas, Oklahoma, and Texas. The Ogallala Aquifer holds enough water to cover all of the United States with water that would be one and a half feet deep.
People drill wells into aquifers so they can bring water to the surface to use. Water in aquifers can be just a few feet below the earth’s surface or hundreds of feet deep. The water that is closer to the surface is easier for us to use, but it can also be more easily polluted than the water that is much deeper.
When we have a drought, people may drill more wells for irrigation or even to make sure that a city has enough drinking water. People may also have to drill wells deeper into the aquifer to find enough water to use. If people use too much water, they may not be able to drill deep enough to get enough water to use.
Canals and Pipelines
Water canals and pipelines have been built in many places to make sure that as many people as possible have access to water supplies. Canals and pipelines are used to transport water from reservoirs and wells to farmers for irrigation and cities for drinking water. Canals like the Central Arizona Project and the Los Angeles Aqueduct carry billions of gallons of water each year to areas that do not have enough water.
Desalination
We need fresh water for drinking, for our daily activities, and for growing our food. But almost all of the water on the surface of the earth is salt water from the oceans and seas. In fact, 97 percent of all water on earth is salt water.
People have been trying to find a way to use ocean water in place of fresh water for many years. With new technology, turning seawater into water that we can drink and use is becoming much easier and much cheaper. Desalination, or removing salt from seawater, is still expensive, but some cities in the United States and other countries are building desalination plants to help them meet their water needs.
The Tampa Bay Desalination Project in Florida is the largest desalination plant of its kind in the United States. Other plants are being planned in states such as California, Texas, and Hawaii. Other countries, like Japan and Korea, also have desalination plants.