Rainfall that stays in the liquid state becomes runoff that makes up streams and rivers.  Water that is not used for some purpose eventually flows to the ocean.  Water that evaporates from the oceans then condenses and eventually falls back to Earth in the form of rain. This is also known as the hydrologic cycle. 

The water cycle is the continuous movement of water in the atmosphere, over the land, and in the ocean. Through precipitation, water condenses, forming a liquid and falling to the Earth as rain, snow, hail or fog.  Once on the ground, water either remains in its liquid state, freezes, becoming ice or evaporates, becoming a gas. For a full-szed chart of the water cycle, click here.  

An acre-foot is commonly used to measure water volume. It is the amount of water needed to cover one acre (43,560 square feet) with one foot of water.  One acre foot is equal to 325,851 gallons of water. 

In Texas, surface-water rights are governed by duel doctrine that take widely differing approaches: riparian and appropriation. The riparian doctrine was introduced to Texas more than 200 years ago during the Spanish colonial period and has since incorporated elements of English common law.

Under this doctrine, property owners have a right to draw water from a stream or water body that crosses or borders their land. They are allowed to take water for a reasonable use and are protected against unreasonable use by others. The right has an emphasis on use of natural flow, meaning the rights cannot be claimed for long-term storage, such as a reservoir. These rights allow only for smaller-scale use on the property, such as irrigation, and the water is not to be transferred to land that is not adjacent to the stream. This water may not be used for commercial purposes. 

Greywater is wastewater from household or small commercial establishments that includes water from clothes washing machines, showers and bathtubs, and sinks used for hand washing.  Greywater does not include water from the kitchen sink used in the cleaning of food and from toilets, dishwashers, or water used for washing diapers.

In some areas, greywater may be released into the environment without going through a treatment process. Texas laws prohibit the release of greywater into or near lakes streams and other bodies of water.

Artesian, spring, well and ground water comes from an underground aquifer and may or may not be treated. Well and artesian water are tapped through a well.

• Spring water is collected as it flows to the surface, and ground water can be either.
• Distilled water comes from steam from boiling water that is condensed. Distilling kills microbes and removes minerals, giving water a “flat” taste.
• Drinking water is simply intended for human consumption and can come from a variety of sources, including public water supplies.
• Mineral water is ground water that naturally contains 250 or more parts per million of total dissolved solids.
• Purified water comes from any source but has been treated to meet the U.S. Pharmacopeia definition of purification. It is essentially free of     chemicals, dissolved solids, and microbes.
• Sterile water comes from any source but is treated to meet U.S. medical standards for sterilization so it contains no microbes.
• Carbonated, seltzer, tonic, sparkling, and soda water are considered soft drinks and are not regulated like bottled water.

The main difference in the water from your faucet and bottled water is the source. Water from your faucet comes from a local source, where ground or surface water is treated for contaminants at a municipal plant before it is sent through pipes to your home. In the case of some rural residents, their water is drawn directly from the ground through nearby wells.

Bottled water can come from a wide variety of sources ranging from artesian wells to public water supplies anywhere across the country. While some may drink bottled water thinking it comes from a more pristine source than their city water supply, this is not necessarily the case.  Federal law sets standards for the quality of drinking water, with the Environmental Protection Agency (EPA) monitoring public water systems and the Food and Drug Administration (FDA) oversees bottled water. Some bottled water is treated more than tap water and some is not treated at all.

Just as one can check with local officials to see local annual water quality reports, one should also check the label of bottled water to learn of its source, possible contaminants and dissolved minerals, and how it is treated.

Another difference can be the taste. Bottled water may not have the disagreeable odor and taste occasionally associated with some public drinking water,. However, the lack of an odor or taste does not mean that the bottled water is cleaner.

Another difference many critics of bottled water point to is its cost to the consumer compared to tap water and the impact on the environment of the water’s plastic or glass packaging.

Your water comes from either a nearby lake or from groundwater.  Where your water originates depends largely on where you live. Water sources can vary between surface water and ground at different locations within a relatively small geographical area. Many municipalities blend both surface water and ground water together before sending it to you home. 

The State of Texas requires that your water provider inform you of where your water originates.  Most providers send this information in the form of a flyer or newsletter in your water bill.  You may also obtain this information by contacting your water provider.

There are many other uses for water besides that used for drinking.  Water is used for agricultural, industrial, environmental, and other municipal purposes.

Municipal use includes supplies to homes and businesses (including schools and prisons) as well as industrial purposes. Numerous municipal needs range from sanitation and sewage systems to food preparation and landscaping.

Water is used in industry throughout the manufacturing process as well as in the gathering of raw materials such as mining and drilling for oil and gas. Water is also an important element in the power industry, playing a vital role in generating electricity.

Water is also used for agriculture both in the care of livestock and in the irrigation of crops. It is also essential in maintaining the health of Texas streams and other bodies of water and the plants and wildlife in and around them.

Surface water consists of all water that is naturally exposed to the atmosphere including creeks, ponds, rivers, lakes, reservoirs, seas and oceans. Also in this category are springs and wells that are directly influenced by surface water sources.

Groundwater is water found beneath the Earth’s surface that gradually seeped down by saturating soil or rock. This water is stored in underground crevices and in the pores of rocks and other materials beneath the surface.

Water is a substance that is essential for the survival of all known forms of life. It covers more than 70 percent of the Earth’s surface, though much of that water is too salty for consumption without treatment.

On a molecular level, water is a mixture of hydrogen and two oxygen atoms, and is found most often as a liquid.  Below 32 degrees Fahrenheit or 0 degrees Celsius, it becomes a solid, in the form of ice.  At its boiling point, water becomes a gas or vapor. 

Though the Earth’s population continues to grow, water is a finite resource.  Planning for the development of additional potable water sources through new treatment technologies or through conservation efforts will be essential to our future.