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Barton Springs
There are four main spring orifices that are the only known habitat for the Barton Springs salamander, a federally listed endangered species. These four springs are the primary discharge point for the Barton Springs segment of the Edwards Aquifer. Main Spring, also known as Parthenia Spring, feeds the 900' long swimming pool. There is a dam at each end of the pool; the upper dam directs flow from Upper Spring and Barton Creek into a bypass culvert so that stormwater flows do not enter the swimming area. Old Mill Spring, sometimes called Walsh or Zenobia Spring, is just south of Barton Creek about 450' below the lower dam. Upper Spring occurs about 1,200' above the swimming pool. The fourth spring, Eliza Spring, is adjacent to the swimming pool and is surrounded by a deep concrete ampitheatre that used to also be a swimming hole but is now reserved for the salamanders.
It has long been accepted that a groundwater divide separates this portion of the Edwards Aquifer from the central (San Antonio) portion and the large springs in San Marcos, New Braunfels, and San Antonio. But in April 2010 a study commissioned by the Guadalupe-Blanco River Authority found that groundwater level data indicates the groundwater divide dissipates and no longer hydrologically separates the two segments during major droughts and current levels of pumping. As a result, there is potential for some groundwater to bypass San Marcos Springs and flow toward Barton Springs during major droughts. The groundwater divide appears to be influenced by recharge along Onion Creek and the Blanco River and is vulnerable to extended periods of little or no recharge and extensive pumping. See the complete study.
For Barton Springs, about 85% of Aquifer recharge comes from six major surface streams that cross the recharge zone: Barton Creek, Onion Creek, Slaughter Creek, Bear Creek, Little Bear Creek, and Williamson Creek (Slade, Dorsey, and Stewart, 1986). During storm events, sinkholes and fractures in the stream bed can quickly provide large volumes of water to recharge. Dye-tracing studies have found that several preferential ground-water flow paths lead to the Springs and that the four springs do not all receive water from the same flow paths (BSEACD, 2003 and Hunt, Smith, Beery, Johns, and Hauwert, 2006). Dye-tracing studies have also revealed that underground flow velocities toward the Springs are highly variable and can be quite rapid, up to six miles per day (Hauwert, Samson, Johns, and Aley, 2004). Swimmers notice that waters in the pool can become quite cloudy and turbid after rain events, especially when low flow conditions prevailed before the rain. The theory about why this occurs is shown below:
In January 2003 the pool was closed for 90 days for environmental testing after the Austin American-Statesman reported that high levels of arsenic and seven benzene-based compounds were found in the pool and upstream on a hillside overlooking Barton Creek. It was suggested that a possible source of the contamination was wastes dumped from nearby coal gasification plants that produced fuel for city lighting from the 1870s to 1928. Subsequently, it was determined the contaminant levels do not pose a threat and are from urbanization, not a waste dump. Retired hydrologist Raymond M. Slade, Jr., who supervised and authored many scientific studies on Barton Springs during his working career, prepared a detailed professional opinion on the matter and you can read it here. Mr. Slade concluded that although the water quality of Barton Springs is still well within swimming criteria, it is likely that uncontrolled urbanization in the watersheds feeding the Springs will eventually cause Barton Springs to be degraded to the extent that it must be permanently closed to swimming. In 2006, the United States Geological Survey published a Scientific Investigations Report that summarized water quality sampling performed from 2003 to 2005. Barton Springs was found to be affected by persistent low concentrations of atrazine (an herbicide), chloroform (a by-product of drinking water disinfection), and tetrachloroethane (a solvent). Concentrations peaked 1-2 days after storm events, and Upper Spring was found to be more contaminated and influenced by a contributing flow path that is separate from those leading to the other springs under all but stormflow conditions. The geochemical response at the Springs after storm events led the authors to conclude that when there is flow in the recharge streams, water directly enters conduits and is transported straight to the Springs. When there is no flow in recharge streams, water drains from the surrounding limestone matrix into the conduits that feed the Springs. You can get the report from the USGS website or right here. Citizens have been fighting for decades against insensitive development that threatens Barton Springs. In the 1990s, residents overwhelmingly passed a Save Our Springs ordinance that would have implemented strict development controls. It was subsequently nullified by the state legislature, which passed a law allowing any development plat already on file to be completed without regard to the new controls. In 2008, the fight to preserve Barton Springs was the subject of The Unforseen, a documentary co-produced by Robert Redford, who learned to swim there as a child. The movie uses the struggle over development in the Barton Creek watershed to illustrate the many clashes between private property rights and resource protection that are occurring across the country. The film drew great reviews, but some developers said it went too far and portays them unfairly. Environmentalists said the movie is not hard enough on those who would develop lands at the expense of common resources like Barton Springs.
In May of 2011 the United States Geological Survey published a fact sheet that summarized its fundings on increasing nitrate concentrations in Barton Springs. Nitrates are a nutrient that can cause blooms of algae when present in excessive concentrations. When the algae dies and decomposes, dissolved oxygen in the water is used and levels of oxygen can become so low that fish and other organisms in the aquatic ecosystem cannot survive. The USGS found that nitrate concentrations in Barton Springs and the five streams that provide most of its recharge were much higher from 2008-10 than before 2008. It also found that biogenic nitrogen from human wastes is the probable source. On Onion Creek, nitrate levels were six to 10 times higher than measured previously. Since 2001, the entire Barton Springs contributing zone has undergone tremendous development, and the number of septic tanks and discharges of wastes have exploded. You can get the fact sheet here. Daily discharge measurements since 1978 show that flows from Barton Springs are rarely less than 10 million gallons per day and rarely exceed 80. Flows can vary widely depending on recent weather conditions and can drop rather quickly when dry conditions prevail. The USGS considers these records to be of poor quality, because the operation of the swimming pool can significantly effect the level seen by the water-stage recorder. As with all USGS stations, flow is determined by developing a relationship between water level and discharge. Since the pool is periodically drained for cleaning, there are times when the gage height is not in direct relation to discharge. Some of the precipitous drops and sudden peaks in the chart reflect pool operations, not changes in flow rate. For the latest real-time measurements, visit the USGS page for Barton Springs. For additional information on Barton Springs visit the Barton Springs/Edwards Aquifer Conservation District.
A Brief Barton Springs History As with all the Edwards Aquifer springs, Barton Springs has a record of human history stretching back at least 10,000 years. It is likely that Zilker Park contains layer upon layer of cultural artifacts. In San Antonio's Brackenridge Park where the San Antonio Springs are located, recent (2011) excavations have suggested the entire Park is one large archaeological site, and such is probably the case at Zilker Park too. At Brackenridge, cultural artifacts lie below the surface in just about any location, beginning at a depth of about 18 inches. Archaeologists suspect that a megadrought which occurred between 3,000 and 6,000 years ago forced tribes that had previously inhabited the trans-Pecos region to make greater utilization of the reliable water sources along the Texas "Spring Line" - the Balcones Escarpment corridor that parallels I-35 and contains most of the major Edwards springs, including Comal Springs and San Marcos Springs (Tomka, 2011).
The earliest known excavations along Barton Creek were conducted in 1929 at Barton Springs by J. E. Pierce of the University of Texas at Austin (Pipkin and Frech, 1993). In a letter to a colleague, Pierce wrote:
The numerous entradas, or formal expeditions, made by Spanish explorers between 1709 and 1722 undoubtedly encountered the ancient thoroughfares that cross-crossed the Texas landscape. These were made by migratory herd animals and the native Americans that pursued them. An old Comanche Indian trail from Bandera county to Nacogdoches passed Barton Springs (Brune, 1981). In 1730, Spanish missionaries chose a site for a mission near present day Zilker Park, but it was occupied for less than a year before the friars moved on to the previously established missions in San Antonio. Its exact location has never been determined. In 1821, the territory came under the control of the Mexican government, which opened up the land to colonization by foreign immigrants. Anglo pioneers began to pour into the region, acting on the Mexican government's promise of 177 acres of farmland and an additional league (4,428 acres) for each family. In 1837, William Barton and his family settled at the springs that would later bear his name. At the time, his nearest neighbor was Reuben Hornsby, eleven miles away at Hornsby's Bend. Barton had settled nearly 10 years earlier with Stephen F. Austin's colony in Bastrop, but when another family moved within earshot, Barton decided to pull up stakes and move upriver to a more private spot (Pipkin and Frech, 1993). Barton built a cabin on the bluff overlooking the present day swimming pool, and named the three springs grouped near his cabin after his daughters, Parthenia, Eliza, and Zenobia (the names never stuck, except for Eliza). If Barton sought solitude, he picked the wrong place, because others had designs on the sleepy little town of Waterloo, which lay just across the river. The Republic of Texas had achieved independence a year earlier (remember the Alamo?) and it soon began a search for a new capital city. A survey committee picked the town of Waterloo. In a letter to Mirabeau B. Lamar, the selection committee praised nearby Spring Creek, which afforded "the greatest and most convenient flow of water to be found in the Republic." Barton's springs began to supply the new city, and in December 1839 he agreed to "give possession of stream of water from my Big Spring" to furnish power for a sawmill. He died four months later, before the mill was built.
The Springs became a popular site for picnicking, fishing, and swimming, and they were also the primary source of water for many local families. In 1901, Andrew Jackson Zilker purchased Barton Springs and 350 acres surrounding them. When droughts ravaged central Texas between 1910 and 1917, the practical need for drinking water gained attention from city leaders, and a military camp proposed for Austin at the time also stipulated a guaranteed water supply. Barton was a staunch advocate of manual-skills education, and he gave the city the tract containing Barton Springs on the condition the city would give $100,000 to the Austin School District earmarked for manual training at Austin High School. Before he died in 1934, he granted additional acreage that is now Zilker Park to the city, once again in return for funds dedicated to manual training (Pipkin and Frech, 1993). During World War I, army troops were stationed in Zilker Park and they used Barton Springs as a bathing area. Large baptismal ceremonies attended by hundreds were frequent events. There was no dam creating a pool as exists today, and Barton Springs lifeguard Ed Barlow reports that in the early 20s, they would pile up rocks each spring and use moss to plug the holes, which brought the water up so people could swim (Barlow, 1993). In 1922 the Chamber of Commerce and the Lions Club built a permanent bath house at a cost of $8,000. They began charging 10 cents, but you could easily slip in on the other side of the pool without paying (Kooch, 1993). That same year, construction started on the Barton Springs dam and an enlarged pool.
In 1928 the firm of Koch and Fowler produced a plan for the city of Austin that advised "playgrounds and recreation facilities are as much a necessity to the health and happiness of people as are its schools, sewer systems, water supply, pavements, and drainage." The next year, a $30,000 improvement project was proposed. On September 23rd the Austin Statesman wrote:
By 1936, the array of activities available in Zilker Park included swimming, horse-back riding, camping, tennis, shooting, boating, and dancing. Water pageants and music events were held throughout the spring and summer. Almost every day, an intellectual circle led by two legendary Texas writers, naturalist Roy Bedichek and folklorist J. Frank Dobie, would meet for discussion and contemplation at the large rock next to the diving boards. They were occasionally joined by historian Walter Prescott Webb. This became known as The Rocksitters Era, and the rock is still known as Bedichek's Rock. Throughout the 1940s and 50s, Barton Springs remained an essential destination for many Austin residents. Austin and Barton Springs were Texas' best kept secret. It was a lovely place that seemed to have found the right balance between protection of natural resources and development. It was largely taken for granted that Barton Springs would always be there. But in January of 1961, stunned Austinites woke up one morning to learn that Austin's natural beauty had suffered a fatal catastrophe, a major fish kill in Town Lake. Over the next three weeks, a wave of poisonous substances moved downstram and killed almost every fish in the Colorado River between Austin and the Texas coast. It was found that a chemical plant had been routinely disposing of insecticides like DDT and chlordane into a storm sewer for over 10 years. The kill was triggered when high-pressure flushing of the storm sewers released a mass of toxins. Traces of chemicals can still be found in the sediments of Town Lake to this day. In 1962 this event was detailed by Rachel Carson in Silent Spring, the book that started the modern environmental movement. In 1970, responding to the first threats of major construction on Barton Creek, the Austin Environmental Council filed a class-action suit seeking to declare Barton Creek a navigable waterway open to the public for recreational uses. In a time before the Clean Water Act, such a suit was one of the only tools available to preserve creeks. Around the same time, several landowners began negotiations to sell property along Barton Creek either to the city or to developers. The city turned down an offer to buy the property where apartments loom over Barton Springs today, and it also passed on many golden opportunities to purchase thousands of acres upstream in the Barton Creek watershed that is now densely developed. Today, Austin's natural beauty is a shadow of its former self, and the future of Barton Springs seems dim. Texas is struggling to find the right balance between protection of common resources and private property rights, and currently the pendelum is swinging strongly in favor of landowners, not residents. Some Barton Springs photos
Postcards from Barton Springs Compared to other Edwards springs like San Pedro and San Marcos, there are not too many Barton Springs postcards out there.
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