What is the water cycle?

by The Brazos River Authority

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-sized chart of the water cycle, click here.

What types of contaminates can be found in drinking water?

by The Brazos River Authority

No water is completely pure.  Contaminates, both naturally occurring and manmade, occur at differing levels depending on your location throughout the world. 

In the United States, federal and state regulations set standards for the maximum amount of contaminants allowed for water to be considered safe for drinking.  Regulated contaminants include a variety of microbes and substances that at certain levels could cause adverse health effects.

Though most treated drinking water is safe for consumption, some contaminants can be introduced into the water after it is treated. One example is water that comes in contact with lead that can leach into water from the pipe systems in older homes.

Other contaminants that are not regulated as potentially harmful, may yet affect water’s aesthetic quality. Higher levels of minerals in hard water may give water a metallic or unpleasant taste as well as odor and cloudy appearance. Substances such as geosmin, produced by algae, can give water an unpleasant taste and odor.

While some regulated contaminants are considered safe for the average person at levels allowed under government regulations, they could pose a hazard for those with weakened immune systems. People with immune systems compromised through illness, chemotherapy or transplant medications should take a closer look at the treatment of the water they drink, whether from their tap or a bottle.

A potentially hazardous contaminant is cryptosporidium, a microscopic parasite that lives in intestines of warm blooded animals including humans and is passed with waste.  In healthy people, the parasite can cause illness with symptoms including diarrhea, vomiting, fever and dehydration among others. Cryptosporidium can prove deadly for those with weakened immunity. The parasite is very resistant to chlorine-based disinfectants and boiling is considered the most effective way of killing it.

An emerging category of pollutants includes pharmaceuticals and personal care products. Though scientists have found no evidence of adverse effects on human health, some studies suggest these substances can harm the environment.  Research continues on the issue.

Why do lake levels fluctuate?

by The Brazos River Authority

Despite a common misconception, there are very few “constant level lakes,” and none operated by the Brazos River Authority.  A constant level lake is one that is artificially managed to remain at a specific level essentially by using another source of water to replenish losses due to evaporation, etc.  

Several factors can affect a lake’s level and only some are within human control. The chief factor that is not controllable is the impact of climate.  Evaporation is a constant, natural part of the water cycle that causes the liquid form of water to change into gas or vapor and move into the atmosphere reducing the amount of  water in a lake.


During periods when outdoor temperatures rise, the rate of evaporation increases. During periods of drought the effect is even more dramatic.


As temperatures rise, increased demand by residents, agriculture, cities, industry, power plants and others on water stored can also draw down a lake’s level.  This impact is exacerbated during periods of extended drought.

Though it can be frustrating for those who live near Texas lakes or turn to them for recreation, dropping lake levels during a drought are also a sign that a reservoir is successfully meeting one of its basic obligations: supplying water to thirsty Texans during a time of need. 


How fast does the river flow? How is it measured?

by The Brazos River Authority

A rivers speed is measured by cubic feet per second (cfs) or how quickly a cubic foot of water passes by a set point for a period of one second.  The set point is usually a gauge managed by the United States Geological Survey (USGS) set at intervals along a water course. You can find how fast the Brazos River and its tributaries flow by going to this link.


What is streamflow?

by The Brazos River Authority

Streamflow is the water discharge in a natural channel.  Streamflow is measured in cubic feet per second (cfs) and monitored by the United States Geological Survey.  You may view the stream gages in the Brazos River basin by clicking here




What is an acre-foot?

by The Brazos River Authority

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. 




What is runoff?

by The Brazos River Authority

Runoff is that part of precipitation, snow melt or irrigation water that does not sink into the ground but moves from the land into streams or other surface water. It can carry pollutants from the land or air to its destination waters.








What is Possum Kingdom Lake?

by The Brazos River Authority

Possum Kingdom Lake, located on the main stem of the Brazos River northwest of Fort Worth, was the first water supply reservoir constructed in the Brazos River basin. Located in Young, Palo Pinto, Stephens, and Jack counties, the construction of the Morris Sheppard Dam was begun in 1938 and completed in 1941 with the aid of the Works Progress Administration Program.

Possum Kingdom Lake covers an area of 16,716 acres with 219 miles of shoreline. The reservoir holds approximately 750,000 acre feet of water with 540,340 acre feet available as water supply for the Brazos basin. The permitted yield of the reservoir is 230,850 acre feet.  Depth of the reservoir varies with the original terrain of the area and is approximately 100 feet at the dam site.

Named for the United States Senator who was instrumental in obtaining funding for the project, the Morris Sheppard dam is 2,700 feet long and 190 feet high. The dam consists of nine crest "roof weir" type gates, each approximately 74 feet long and 13 feet high for the passage of floodwaters. Each gate passes approximately 9,600 cubic feet per second (cfs) of water when open.

The Morris Sheppard Dam was constructed as a hydro electric generating facility with two 11,250 kilowatt generators. Categorized as a "peaking plant," the generators supplied electricity during high demand periods from 1941 to 2007 when the generators were shut down. The plant was decommissioned in 2013.

Possum Kingdom receives an estimated three million visitors annually. Major activities on the reservoir include fishing, water skiing, and scuba diving. The reservoir has public fishing piers, seven public boat ramps, public access areas for picnicking, and a total of 400 primitive camp sites.

To view a copy of the Possum Kingdom Lake permit, click here



What is in untreated water that can make you sick?

by The Brazos River Authority

Water drawn from rivers, lakes stream and other bodies of water as well as groundwater can be contaminated and could make you sick if you drink it without treating it first. Waterborne diseases, caused by microorganisms that live in untreated water, can cause diarrhea, nausea vomiting and other symptoms, and in extreme cases, death.

Many of these pathogens infect water through contact with human and animal feces, carried there by runoff or seeping into the water supply from leaking sewage or septic systems. 


Water can also be contaminated by any pollutant improperly handled by man, such as dumped chemicals, or fertilizers and other chemicals used in agriculture that wash into lakes and streams.


Some contaminants, including microbes and chemical elements, can occur naturally in the ground surrounding the water. Though soil and rock can filter water as it percolates down into groundwater supply, such water can also become contaminated by natural and manmade pollutants and pathogens. For more information on waterborne diseases and contaminants, click here.


What is Lake Granbury?

by The Brazos River Authority

DeCordova Bend Dam and Lake Granbury were constructed by the Brazos River Authority and are maintained and operated by the BRA as a source of water supply.

Construction of the project began in December 1966 and was completed in September 1969. The reservoir provides 129,011 acre-feet of storage capacity for conservation of flood and storm waters to meet requirements of municipalities, industries, agriculture and mining.  The reservoir has a permitted yield of 64,712 acre feet.  To view the state permit establishing Lake Granbury, click hereThe DeCordova Bend Dam contains 16 computer-operated gates to pass flood water releases.

The reservoir has a surface area of 7,945 acres with 121 miles of shoreline.  Five public access areas for picnicking and fishing and four BRA-maintained boat ramps are available for recreational use.   

Lake Granbury was built without use of tax dollars, financed entirely with revenues from sales of water contracts. The principal revenues used to finance the project were provided under a contract with TXU Electric Company for purchase of water for industrial use, including cooling water for a natural gas-fired steam electric power plant and the Comanche Peak Nuclear Power Plant near Glen Rose. The reservoir also furnishes raw water for municipal use in Hood and Johnson counties. 


What is the Brazos River Authority and what do they do?

by The Brazos River Authority

The mission of the Brazos River Authority (BRA) is to develop, manage, and protect the water resources of the Brazos River basin. The BRA was created by the Texas Legislature in 1929 and was the first state agency in the United States created specifically for the purpose of developing and managing the water resources of an entire river basin.

The water stored in the three BRA-owned reservoirs and eight US Army Corps of Engineers reservoirs within the system is permitted for use by the state’s water oversight agency, the Texas Commission on Environmental Quality (TCEQ). The TCEQ manages the state’s surface water assets and determines the amount of water made available through the issuance of water rights permits.  

The BRA also works with three Texas Regional Water Planning groups to find the means to provide for the future of water supply within the state.

Besides water supply, the BRA works to ensure the quality of the water within the basin by providing services such as potable water treatment, wastewater treatment and continuous monitoring for specific contaminates as part of the Texas Clean Rivers Program.  

 Although the Brazos River Authority is a political subdivision of the State of Texas, it does not levy or collect taxes and does not receive subsidies from the state or the counties it serves.  Except for occasional governmental grants to aid in the cost of specific projects, the BRA is funded entirely through the management of water and wastewater services and the sale of water supply.   



What is the mission of the Brazos River Authority?

by The Brazos River Authority

The mission of the Brazos River Authority is to develop, manage and protect the water resources of the Brazos River basin.

Where is Lake Limestone?

by The Brazos River Authority

Lake Limestone, located on the upper Navasota River in Limestone, Robertson and Leon counties, is a water supply reservoir built by the Brazos River Authority in 1978.  Construction of the reservoir was made possible through the sale of water to Texas Electric Utilities to be used by their lignite-burning electric plants in the area.  To view a copy of the Lake Limestone state permit, click here.

Water from the reservor is supplied for similar use at a NRG steam-electric plant just east of Lake Limestone and a Texas Municipal Power Agency power plant located near the Navasota River 50 miles downstream.

Lake Limestone was formed by the building of the Sterling C. Robertson Dam. Constructed of earth and concrete, the dam runs 8,395 feet and stands 72 feet tall. An emergency spillway measuring 3,000 feet is made of concrete and houses five tainter gates for water release. The depth of the lake near the dam is 43 feet. 

The waters of the reservoir are open for free public access via four boat ramps at various locations around the reservoir for boating, swimming, fishing and other recreational activities.

When full, the reservoir covers a surface area of 12,553 acres with 98 miles of shoreline. It contains a conservation pool of 208,017 acre-feet and a permitted yield of 65,074 acre feet of water supply.

The project was built entirely without use of tax dollars with funding for the reservoir being financed by revenues from the sale of water supply contracts.   

Who serves on the Brazos River Authority Board of Directors?

by The Brazos River Authority

The Brazos River Authority Board of Directors is made up of 21 men and women from across the Brazos basin who are appointed by the Texas Governor. They serve staggered six-year terms. For a list of current board members, their photos and biographical information, go here.



How is the Brazos River Authority governed?

by The Brazos River Authority

The Brazos River Authority is governed by a Board of Directors. Board members are appointed by the Governor of Texas with advice and consent of the state Senate. The organization is accountable to the Governor, the Legislature, the Texas Commission on Environmental Quality (TCEQ) and the cities, businesses and individuals throughout the basin to whom we sell water.


What is the Texas Clean Rivers Program?

by The Brazos River Authority

The Texas Legislature created the Clean Rivers Program in 1991 when it passed the Texas Clean Rivers Act. Legislators’ goal was to push Texas towards comprehensive water planning and management to ensure the future quality of the water supply.

The state designated the Brazos River Authority as the lead agency to conduct water quality assessment and Clean Rivers Program (CRP) planning in the Brazos River watershed. Every one to three months depending on location, the BRA tests water for everything from temperature and salinity to dissolved solids and chemical contaminants at more than 100 sites. 

If that data indicates there is a problem, officials could respond with a watershed protection plan. A WPP is a means for the community to come together to discuss and plan ways to resolve water quality issues.

More severe issues might call for a government mandated Total Maximum Daily Load Program which limits the discharge of certain contaminants. An example of the program’s success can be found at Lake Aquilla, where officials worked with farmers to reduce levels of herbicide in the water.  More information on the Clean Rivers Program may be found by clicking here.


What are system operations?

by The Brazos River Authority

Authorized by the state, the Brazos River Authority’s system operations permit allows the BRA to sell up to 705,000 acre-feet of water basin-wide from the 11 system reservoirs and the rivers within the watershed. The system permit allows the BRA to draw the water from any of the reservoirs and rivers included in the system allowing the BRA to utilize the sources with the largest storage of water at any specific time.  For a full size map, click here



What is wastewater?

by The Brazos River Authority

Wastewater is water that has been used in homes, industries, and businesses that has been in contact with human or industrial waste and cannot be reused or returned to the water cycle until it has been treated or cleaned.

How is wastewater cleaned?

by The Brazos River Authority

While exact methods can vary, here’s a general breakdown of the municipal wastewater treatment process:

  • When wastewater leaves a home or business, it is transported through municipal collector pipelines usually by the force of gravity, to a wastewater treatment plant. If gravity flow is not available all the way, then a lift station may pump the wastewater up to a level where gravity flow can again take place. 
  • As wastewater enters the treatment plant, it is screened to remove non-sewage items such as rags, clothing, toothbrushes, or any other solids that might damage or clog the equipment. This material is sent to landfills.
  • The sewage then moves into grit settling tanks where grit is removed to a landfill.
  • Next, the wastewater is sent to aeration tanks, which move the sewage to expose it to oxygen and naturally occurring bacteria.  The bacteria break organics down into carbon dioxide and water and form “floc” which helps settle the remaining inorganic materials.
  • The wastewater then enters another settling tank. Here, the “floc” settles to the bottom and is pumped out as “biosolids”. The biosolids enter either the large “digester” tanks or are returned to the treatment process to reseed the aeration.  
  • In the digester, bacteria further break down or “digest” the organic material. This part of the process takes 20 to 30 days. This digested material, its volume and odor reduced and harmful microorganisms gone, is taken either to a landfill or sometimes further processed for use as a soil conditioner. 
  • From the settling tanks, the wastewater is typically disinfected by chlorine (gas or liquid) or by the ultraviolet light before being discharged to the receiving stream.

The Authority owns and operates one treatment system, the Temple-Belton Regional Sewerage System. The Authority also operates wastewater systems for the cities of Hutto, Clute/ Ridgewood, Georgetown, Sugar Land, Liberty Hill, Lee County Fresh Water Supply District No. 1, and the Brushy Creek Regional wastewater system which serves the City’s of Round Rock, Cedar Park, Austin and the Fern Bluff and Brushy Creek MUDs.  



What is a drought?

by The Brazos River Authority

A drought is generally considered to be a prolonged period of less-than-normal precipitation such that the lack of water causes below average streamflow or lake levels, lowered soil moisture, crop damage, or economic losses.   








What is a flood plain?

by The Brazos River Authority

A flood plain is any normally dry land area susceptible to inundation by water. This area is usually low, flat and next to a stream or other body of water.




What is the Brazos River?

by The Brazos River Authority

The Brazos River is the longest river contained entirely in Texas, with its watershed stretching from New Mexico to the Gulf of Mexico. The Brazos River draw lies approximately 50 miles west of the Texas-New Mexico border, beginning a watershed that stretches 1,050 miles and comprises 44,620 square miles, 42,000 of which are in Texas.

The Brazos River proper is formed at the confluence of the upper forks of the river, the Salt and Double Mountain, in Stonewall County. The Clear Fork joins the river just above Possum Kingdom Lake in Young County. The river enters the Gulf of Mexico two miles south of Freeport in Brazoria County.

The Brazos crosses most of the physiographic regions of Texas -- the High Plains, West Texas Rolling Plains, West Cross Timbers, Grand Prairie and Gulf Coastal Plains -- offering a variety of landscapes including canyons in the upper portion, rolling hills and plains in the central and beaches near the Gulf. The river descends at a rate of three feet to one-half foot per mile flowing 820 miles down to the Gulf of Mexico.

In addition to the Salt, Double Mountain, and Clear Forks, there are five other principal tributaries along the Brazos River. These include the Clear Fork, Yegua Creek and the Bosque, Little and Navasota Rivers.  Within these tributaries are 15 subtributaries, including the Leon River, a tributary of the Little River.

The most prevalent cities in the Brazos River basin are Lubbock, Graham, Waco, Temple, Belton, Freeport and Galveston with the major metropolitan cities of Dallas-Fort Worth, Austin and Houston lying just outside the watershed boundaries.

Like the terrain, the climate throughout the river basin varies significantly, from temperate to subtropical. The average annual temperature ranges from 59 degrees in the upper basin to 70 degrees in the coastal area. Although winters are typically mild and brief, temperatures below zero have been recorded.

Rainfall averages from 16 inches annually in the northwest to 47 inches in the southeast region. The soil along the basin ranges from sandy loams to deep clay. Natural vegetation consists of grasses in the dry portions to hardwoods in the wet portions. Farming and ranching is possible in almost all areas in the basin. Cotton, cattle and oil have been the most prominent products.

The first permanent settlement on the river was San Felipe de Austin at the Atascosito Crossing of the Brazos. Founded by John McFarland, a member of one of Stephen F. Austin's "Old Three Hundred" families, the town became the colonial capital of Texas.

The Brazos at Velasco was the scene of the first colonial resistance to Mexican authority. The Brazos River settlements of Columbia and Washington-on-the-Brazos served as the first two seats of government of the Republic of Texas.

Navigation of the river became a priority to many Texans in hope of expanding trade throughout the state. With river flows alternating between drought and floods, the task was difficult as best. In the early 1900s the US Army Corps of Engineers began building a series of locks that would allow navigation as far north as the City of Waco. However, a major flood destroyed the majority of work begun and the Corps chose not to rebuild.

The natural mouth of the river was located at Quintana, two miles southeast of Freeport. However, shifting Gulf sandbars created a hazard to shipping and in 1929 the US Army Corps of Engineers diverted the mouth of the river a few miles down the coast.  


Where can I find a map of the Brazos basin?

by The Brazos River Authority

A variety of maps of the Brazos basin can be found on the BRA’s website by clicking here.




What is an outhouse?

by The Brazos River Authority

An outhouse, commonly referred to as a privy in the Texas Statutes, is a type of toilet without plumbing in a small building separated from a main structure. Instead of being connected to a sewer or septic system, an outhouse sits over a pit.

In an outhouse however, bacteria that thrive in oxygen break down the waste, with help from other natural processes. Eventually the pit fills, is covered with dirt and the outhouse is relocated.



Under Texas law, an outhouse may not be built within 75 feet of a drinking water well or a human habitation other than the residence to which the privy belongs, without approval from local health authorities. An outhouse also may not be built over an abandoned well or a stream. For more regulations on outhouses, consult the Texas Statutes. Pertinent information can be found here




What is water conservation?

by The Brazos River Authority

Conservation is the careful management and use of water to assure it provides the best long-term benefit to the public. Conservation is preservation of water from loss, damage or neglect.





What is flood stage?

by The Brazos River Authority

Flood stage is an established gage height within a creek or river above which a rise in water surface level is described as a flood. This is the elevation at which the overflow of the natural banks of a stream or body of water begins.



What is groundwater?

by The Brazos River Authority

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.






What is a water well?

by The Brazos River Authority

A water well is an artificial hole dug to access groundwater from aquifers.

What is aerobic treatment?

by The Brazos River Authority

Aerobic water treatment is a method of treating sewage and wastewater by adding oxygen to the waste.  This process encourages naturally occurring bacteria to break down the waste and produce a higher quality effluent that may then be treated with chlorine to remove the remaining bacteria.






What is subsidence?

by The Brazos River Authority

Subsidence is a drop in the surface level of land.  It sometimes occurs when groundwater is pumped from an aquifer. During this virtually irreversible process, cracks, fissures and sink holes can appear in the ground. 


The southern area of the Brazos River basin has experienced a great deal of subsidence.  To combat this problem, regulatory bodies known as subsidence districts were created by the State of Texas to begin lowering the use of groundwater and moving to a larger use of surface water in order to reduce groundwater pumpage and thereby slow the subsidence of the terrain near the Gulf of Mexico.


In addition, the legislature added language to the Texas Water Code explicitly recognizing groundwater conservation districts as the “preferred method of determining, controlling, and managing groundwater resources”(§36.0015)   By statute, the purpose of groundwater districts is to “provide for the conservation, preservation, protection, recharging, and prevention of waste of groundwater, and of groundwater reservoirs or their subdivisions, and to control subsidence caused by withdrawals of water from those groundwater resources or their subdivision …” (Texas Water Code §36.0015)


The photo at the left illustrates subsidence in the area thought to have experienced the worst amount of subsidence in the United States.  The signs posted on the telephone pole illustrate the altitude measurements for that location as it experienced subsidence.  (photo courtesy of the USGS.)



What is a water right?

by The Brazos River Authority

Water rights or a water permit is granted by the state in set increments to ensure that water is available for all in need.  


There are several types of water rights in Texas: perpetual rights including permits and certificates of adjudication and limited rights including temporary and term permits.  

administrative test post

by The Brazos River Authority

this is an administrative test post.  We are woriking on the comments portion of the site.


Can I pump water from the river to water my lawn?

by The Brazos River Authority

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. 


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What is volume?

by The Brazos River Authority

Volume is the amount of water in a reservoir measured in acre-feet. 







What is a spillway?

by The Brazos River Authority

A spillway part of a dam that is designed to allow water to flow freely over the dam during floods. Spillways may be used on dams with floodgates as an additional means to control release of water during flooding.  A spillway may also be used as the main area of water release from a dam, allowing water to flow through the spillway only when the reservoir is full. 

What is the Safe Drinking Water Act?

by The Brazos River Authority

The Safe Drinking Water Act is a federal law passed by Congress in 1974 to protect public health by regulating the nation’s drinking water supply.  Under the direction of the Environmental Protection Agency (EPA), the law regulates the dispersal of chemicals, animal waste, pesticides and other items that contaminate drinking water. 

In Texas, the Texas Commission on Environmental Quality (TCEQ) enforces standards  that equal or exceed federal standards. 




What is interruptible water?

by The Brazos River Authority

Interruptible water is water available for contract sale for a specific period, normally a year-to-year basis.  This water is available based on the amount of water in reservoir storage.  Interruptible water is subject to restricted use during water shortages.


What are floodgates?

by The Brazos River Authority

Floodgates are solid metal barriers in a dam that can be opened to release flood waters downstream.








What is a flash flood?

by The Brazos River Authority

The National Weather Service classifies a flash flood as an overflow of water onto normally dry land caused by heavy or excessive rainfall in a short period of time, generally less than 6 hours.

Flash floods are usually characterized by raging torrents after heavy rains that rip through river beds, urban streets, or mountain canyons sweeping everything before them. They can occur within minutes or a few hours of excessive rainfall. They can also occur even if no rain has fallen, for instance after a levee or dam has failed, or after a sudden release of water by a debris or ice jam.




What is a flash flood warning?

by The Brazos River Authority

The National Weather Service issues a flash flood warning to inform the public, emergency management, and other cooperating agencies that flash flooding is in progress, imminent, or highly likely.  For additional information on flood warning and watches, click here



What is "firm" water?

by The Brazos River Authority

Firm water is a supply term referring to the specific amount necessary to fully supply an area with water during a repeat of the most severe drought of record.


What is fecal coliform bacteria?

by The Brazos River Authority

Fecal coliform bacteria is one of a collection of relatively harmless bacteria that live in the intestines of all warm blooded animals including humans.  These bacteria normally aid in the digestion of food then pass through the intestines as part of fecal waste. 


When aquatic systems are contiminated by human or animal feces, the fecal coliform bacteria (the most common form being Escherichia coli or E coli) can cause a number of waterborne diseases including typhoid fever, viral and bacterial gastroenteritis and hepatitis A.  



What is dissolved oxygen?

by The Brazos River Authority

Dissolved oxygen or DO is the amount of oxygen in surface water that is available for aquatic life.  Aquatic plants and algae contribute to the presence of dissolved oxygen.


What is the National Flood Insurance Program?

by The Brazos River Authority

The National Flood Insurance Program is a federal insurance program under which flood-prone areas are identified and flood insurance is made available to residents of participating communities that agree to adopt and enforce floodplain management ordinances to reduce future flood damage.  For additional information and qualification requirements, click here 

What is the gage height or stage?

by The Brazos River Authority

The gage height or stage is the height of the water surface above an established datum point, such as in a river above a predetermined point.  The gage height does not represent the depth of the river.


What is a flood elevation study?

by The Brazos River Authority

A flood elevation study is an examination, evaluation, and determination of flood hazards, and if appropriate corresponding water-surface elevations. The resulting reports are used to develop Flood Insurance Rate Maps. (Also known as Flood Insurance Study)


What is a flood?

by The Brazos River Authority

A flood is any relatively high streamflow that overflows the natural or artificial banks of a stream.


What is discharge?

by The Brazos River Authority

Discharge is the volume of fluid passing a point at a specific point intime, commonly expressed in cubic feet per second, million gallons per day, gallons per minute, or seconds per minute per day.



What is constant level?

by The Brazos River Authority

Constant level is a term given to the practice of maintaining a body of water at a specific elevation.  No natural body of water has a constant level.  While some fluctuate more than others, all natural bodies of water change on a daily basis, some rapidly during floods.  Few man-made reservoirs have the ability to be maintained at a constant level as evaporation, drought, water use and/or flooding affect elevation levels. 





What is cubic foot per second?

by The Brazos River Authority

The measurement cubic foot per second (cfs or ft3/s) is the rate of water movement representing a volume of 1 cubic foot passing a given point during 1 second.  This measurement is equivalent to approximately 7.48 gallons per second or 448.8 gallons per minute.

About us

The Brazos River Authority was created by the Texas Legislature in 1929 as the first state agency in the country with the purpose of developing and managing the water resources of an entire river basin. Today, the Authority develops and distributes water supplies, provides water and wastewater treatment, monitors water quality, and pursues water conservation through public education programs. Although the Authority is an agency of the state, it does not levy or collect taxes and is entirely self-supporting.


The information provided on this site is intended as background on water within the Brazos River basin. There should be no expectation that this information is all encompassing, complete or in any way examines every aspect of this very complex natural resource. 


If you have questions about a post or would like additional information, please contact us at information@brazos.org or call 888-922-6272.