Editing Barton Springs

{{distinguish|text=[[Barton Springs Pool]], a recreational swimming pool, part of Barton Springs}}
{{Use American English|date=January 2025}}
{{Use mdy dates|date=August 2023}}
{{Infobox spring
 |name          = Barton Springs
 |image         = BartonSprings_MainSpring.jpg
 |image_caption = Main Barton Spring, inside [[Barton Springs Pool]]
 |type          = [[Karst|Karst States]]
 |spring_source = [[Edwards Aquifer]]
 |provides      = [[Barton Creek]] and [[Colorado River (Texas)|Colorado River]]
 |discharge     = 66 ft³/s (1869 L/s)
 |magnitude     = 2
 |elevation     = 435 ft (133 m) above [[sea level]]
}}
{{Infobox NRHP
| name         = Barton Springs Archeological and Historical District
| nrhp_type    = hd
| nocat        = yes
| image        = 
| caption      = 
| location     = [[Zilker Park]], [[Austin, Texas]]
| coordinates  = {{Coord|30.26390|-97.77000|region:US_type:landmark|display=inline,title}}
| locmapin     = Texas#USA
| built        = 1891
| architecture = Tudor Revival, Bungalow/Craftsman, Queen Anne
| added        = November 27, 1985
| area         = {{convert|138.5|acre}}
| mpsub        = {{NRHP url|id=64500640|title=HBarton Springs MPS}}{{better source needed|ref explains historical registry of Hyde Park, 1990. Where's the Barton Springs historical reference documentation link.?|date=December 2022}}
| refnum       = 85003213<ref name="nris">{{NRISref |refnum=85003213|2009a}}</ref>
}}
'''Barton Springs''' is a set of four natural water springs located at Barton Creek on the grounds of [[Zilker Park]]<ref>Gregg Eckhardt. 2009</ref> in [[Austin, Texas]], resulting from water flowing through the [[Edwards Aquifer]]. The largest spring, Main Barton Spring (also known as Parthenia, "the mother spring"), supplies water to [[Barton Springs Pool]], a popular recreational destination in Austin. The smaller springs are located nearby, two with man-made structures built to contain and direct their flow.  The springs are the only known habitat of the [[Barton Springs Salamander]], an [[endangered species]].<ref>{{cite web |url= http://www.tshaonline.org/handbook/online/articles/rpb01 |title= Barton Springs |author= Gunnar, Brune |access-date= Sep 12, 2011}}</ref>

The '''Barton Creek National Archeological and Historic District''' was formed in 1985.

==Geology==
Barton Springs is the main discharge point for the Barton Springs segment of the [[Edwards Aquifer]] of Texas, a well known [[karst topography|karst]] aquifer. Geologically, the aquifer is composed of [[limestone]] from the [[Cretaceous period]], about 100 million years old.  [[Fractures]], [[fissures]], [[Channel (geography)|conduits]], and [[cave]]s have developed in this limestone.  Both physical forces, such as [[Fault (geology)|faulting]], and chemical forces, such as dissolution of limestone by infiltrating water, have enlarged these voids.  This results in a karst aquifer made up of limestone with large void spaces. Water then enters the aquifer and fills the voids.<ref>{{cite web |url= http://www.edwardsaquifer.net/barton.html |title= Edwards Aquifer and Barton Springs |author= Eckhardt, Gregg |year= 2009 |publisher= Edwards Aquifer |access-date= Sep 12, 2011}}</ref>

All water discharging from Barton Springs originates as rainfall.  Some of this rain falls directly onto the area of land where the aquifer limestone rock is exposed, which is known as the recharge zone.  Other rainfall enters into creeks that cross the recharge zone, and infiltrates the limestone bedrock. After water enters the aquifer, it flows along the gradients created by differences in hydraulic pressure into the area of lowest hydraulic pressure.  This lowest point of hydraulic pressure is Barton Springs.

===Main spring===
Main Barton Spring/Parthenia is the most famous, yet least visible of the four springs because it is completely submerged by pool water.  Located near the diving board in [[Barton Springs Pool]], the spring's flow is not always visible at the surface.

The main spring discharges an average flow of about {{convert|31|e6USgal|m3}} per day.  The lowest discharge ever recorded was {{convert|9|e6USgal|m3}} per day during the [[1950s Texas drought|drought of the 1950s]], and the highest discharge ever recorded was {{convert|85|e6USgal|m3}} per day during December 1991<ref>{{cite web | url=https://waterdata.usgs.gov/monitoring-location/08155500/#parameterCode=00060&startDT=1991-12-01&endDT=1992-03-31 | title=Barton SPGS at Austin, TX }}</ref> and September 2016<ref>{{cite web | url=https://waterdata.usgs.gov/monitoring-location/08155500/#parameterCode=00060&startDT=2016-07-01&endDT=2016-10-30 | title=Barton SPGS at Austin, TX }}</ref> flooding.  By comparison, a typical domestic in-ground swimming pool holds about {{convert|20,000|USgal|m3}}, and the City of Austin, a city of about 1 million residents, uses about {{convert|120|e6USgal|m3}} per day for its public water supply system.<ref>{{cite web |title=Austin Water Use at Record Low |url=http://www.hillcountryalliance.org/austin-water-use-at-record-low/ |website=Hill Country Alliance |access-date=11 July 2020}}</ref>

==Other springs==
[[Image:Eliza spring.jpg|right|thumb|200px|Eliza Spring in 2005.]]
The three other springs associated with Barton Springs are Eliza, Old Mill, and Upper Barton Spring.  Each is significantly smaller than Main Barton Spring, discharging an average of {{convert|3|e6USgal|m3}} per day.  Sometimes, these springs dry up completely.

Eliza Spring, also known as Concession Spring, is located near the north entrance to Barton Springs Pool, 300 feet (100m) east towards the children's playscape.  During the early 20th century, an amphitheater-style swimming enclosure was built around the spring.  This structure is no longer open to the public due to safety concerns, and the fact that Eliza Spring has become a sensitive habitat area for the endangered [[Barton Springs Salamander]].

Old Mill Spring, also known as Sunken Gardens Spring or Zenobia Spring, is located on the south side of Barton Springs Pool.  Like Eliza Spring, the early 20th century structure built around the spring is now closed to public access due to safety and endangered species habitat issues.  Scientific analysis show that the water at Old Mill Spring has a slightly different chemistry than that of Main Barton Spring and Eliza Spring, even though it is less than half a mile (800 m) away from these springs.

Upper Barton Spring is located in the creek bed of [[Barton Creek]], about a half mile (800 m) upstream or west of Barton Springs Pool.  Frequently dry, Upper Barton Spring is fully submerged by Barton Creek during floods.  The water at Upper Barton Spring also has a significantly different chemistry than the other springs.

The entire area around Barton Springs is riddled with faults from the [[Balcones Fault|Balcones Fault Zone]] and features other, smaller springs.  For example, about one mile (2&nbsp;km) upstream of Upper Barton Spring, an intermittent spring fills a popular natural swimming hole.  Several other small springs empty directly into the Barton Creek bypass tunnel that passes to the side of Barton Springs Pool.<ref>{{cite web |url= http://impactnews.com/southwest-austin/124-history/9125-barton-springs |title= Barton Springs |author= Lai, Valeria |date= July 23, 2010 |access-date= Sep 11, 2011}}</ref>

==Fauna==
Two salamander species are [[Endemism|found only at]] Barton Springs: [[Barton Springs salamander]] and [[Austin blind salamander]].<ref name=frost>{{cite web |url=http://research.amnh.org/vz/herpetology/amphibia/ |title=Amphibian Species of the World: an Online Reference. Version 6.0 |author=Frost, Darrel R. |year=2014 |publisher=American Museum of Natural History |access-date=14 February 2015}}</ref>

==Notes==
{{Reflist}}

==External links==
{{Commons category|Barton Springs}}
*[http://www.sosalliance.org/ Save Our Springs Alliance]
*[http://www.bseacd.org/ Barton Springs/Edwards Aquifer Conservation District]

{{Austin}}
{{National Register of Historic Places in Austin, Texas}}

[[Category:City of Austin Historic Landmarks]]
[[Category:Geography of Austin, Texas]]
[[Category:Historic districts on the National Register of Historic Places in Texas]]
[[Category:Springs of Texas]]
[[Category:National Register of Historic Places in Austin, Texas]]
[[Category:Bodies of water of Travis County, Texas]]
[[Category:Archaeological sites on the National Register of Historic Places in Texas]]