The Espada Aqueduct was built between 1731 and 1745 by missionaries sent to Texas. It is a part of the acequia system that was built for the Espada Mission. Because irrigation was considered crucial, the missionaries built the acequia system before other permanent structures. It became a national historic landmark in 1965.


  • National Landmark Plaque
    National Landmark Plaque
  • Dam, Ditch, and Aqueduct Plaque
    Dam, Ditch, and Aqueduct Plaque
  • View of the Aqueduct from the side
    View of the Aqueduct from the side
  • View of the Aqueduct from above
    View of the Aqueduct from above

Spanish Catholic missionaries were sent to Texas in the early 18th century with two main purposes, the first of which was to protect the Spanish frontier from French invasion and the second to convert the Native Americans to Christianity.The Spanish government and Catholic missionaries united in this attempt to convert the Native Americans.In their joint effort, they “provided training for Indian converts in religion, agriculture and handicrafts."3 The building of churches and other permanent buildings “was deemed less important than establishing an irrigation system” though.4 This was because the missionaries knew that feeding the Native Americans was their first matter of concern. They also knew irrigation to be “vitally necessary for the success of agriculture.”5 The hot and dry climate of Texas made a reliable water source an even higher priority.6 They therefore focused on establishing the acequia system, a complex irrigation system of which the Espada Aqueduct is a part of, before putting much concern towards building more permanent structures.7 The first irrigation ditch was built by the combined effort of the settlers, soldiers, missionaries, and Native Americans.8 The construction of acequias “enabled the missions to thrive… [and] influenced the development of other infrastructure such as historic roadways.”9 The acequia system also allowed the missions to be “self-sufficient communities.”10 It allowed the missions to generate enough food to sustain themselves.11 Back when it was originally built, the acequia system extended for about fifteen miles and irrigated roughly three thousand five hundred acres of land.12

Without the construction of this irrigation system, San Antonio would not have become the “major community” it is today.13 The “system allowed the Spanish settlers to establish their precarious foothold in the wilderness.”14  The Spanish developed social and political structures with the purpose of conserving their water sources so a town was essentially built around the water source. This also gave the settlers the ability to live in larger groups as a form of protection from attacks by the Native Americans. A “larger more defensible and self-sustainable village” was produced.15

The Espada Aqueduct was built as part of the acequia system and was designed to serve the people living in the San Francisco de la Espada Mission, which was founded and run by Franciscan missionaries. Construction began shortly after the mission had relocated from East Texas in 1731 and was completed around 1745.16 It began with a dam, which was an engineering feat in itself, to span the San Antonio River running between the San Jose and San Juan missions. This dam is, in fact, the only Spanish colonial dam that is still working.17 The aqueduct then transported the water over the Piedras Creek and then continued for about 3.2 miles to the Mission Espada.18 A very slight slope, the creation of which showed the genius of the missionaries’ engineering, in the aqueduct allowed gravity to carry the water the whole way.19

The southernmost point of the entire acequia system was five hundred twenty-five feet and was at Mission Espada. In order for the gravity effect to be effective, the “grades of ditches had to be carefully planned and the plan carefully adhered to.”20 The slightest mistake would result either in the erosion of the banks or the grade being too steep for the water to continue traveling its course. Therefore, all of the “difficult muscle work…had to be done skillfully and precisely.”21 The accuracy achieved by the Spanish settlers in the 18th century is made more remarkable by considering the sheer length of the acequia and the fact that the path of the acequia includes numerous sharp twists and turns.22

The Espada Aqueduct further reveals the astounding engineering qualities which the missionaries possessed because even today, almost three hundred years later, it is still functional.23 Existing during a time in which Indian raids were rampant, the survival of the aqueduct is indeed a remarkable feat. Only two out of the seven original acequias still exist and both of them, including the Espada Aqueduct, are still be using by farmers to water fields.24 It is considered the “most remarkable feature” of the acequia system.25 There simply is “no finer example of Spanish colonial engineering and construction” that still exists to this day and is still functional.26

Even though the aqueduct remains intact today, it has still required conservation efforts to help it in doing so. Deterioration became a problem as early as 1794 and no significant repairs were undertaken until 1895. The San Antonio Conservation Society bought the lands surrounding the Espada Aqueduct to help in preserving it. In 1965, the Espada Aqueduct was designated as a registered national historic landmark for its importance in the remembering of Texas history.27

1Reuben Hull, “Nation’s Oldest Aqueduct in Texas Still Thriving Today,” ASCE News, 19 Feb.

2015, news.asce.org/nations-oldest-aqueduct-in-texas-still-thriving-today/.

2Charles R Porter, Spanish Water, Anglo Water (College Station: Texas A&M University Press, 2009), 21.

3Charles R Porter, Spanish Water, Anglo Water (College Station: Texas A&M University Press, 2009), 21

4“Mission Espada (Mission San Francisco De La Espada),” The City of San Antonio – Official City Website, City of San Antonio, 3 March 2018, www.sanantonio.gov/Mission-Trails/Mission-Trails-Historic-Sites/Detail-Page/ArtMID/16185/ArticleID/4461/Mission-Espada-Mission-San-Francisco-de-la-Espada?ID.

5Reuben Hull, “Nation’s Oldest Aqueduct in Texas Still Thriving Today,” ASCE News, 19 Feb.

2015, news.asce.org/nations-oldest-aqueduct-in-texas-still-thriving-today/.

6Reuben Hull, “Nation’s Oldest Aqueduct in Texas Still Thriving Today,” ASCE News, 19 Feb.

2015, news.asce.org/nations-oldest-aqueduct-in-texas-still-thriving-today/.

7Rocio Guenther,“Espada Aqueduct: A Centuries-Old Link to the Spanish Colonial Missions,”

Rivard Report, 8 Sept. 2017, therivardreport.com/espada-aqueduct-a-centuries-old-link-to-the-spanish-colonial-missions/.

8Charles R Porter, Spanish Water, Anglo Water (College Station: Texas A&M University Press, 2009), 31

9“Acequias,” The City of San Antonio - Official City Website, City of San Antonio , 2 March

2018, www.sanantonio.gov/Mission-Trails/Mission-Trails-Historic-Sites/Detail

Page/ArtMID/16185/ArticleID/4230/Acequias?ID=53.

10Reuben Hull, “Nation’s Oldest Aqueduct in Texas Still Thriving Today,” ASCE News, 19 Feb.

2015, news.asce.org/nations-oldest-aqueduct-in-texas-still-thriving-today/.

11Charles R Porter, Spanish Water, Anglo Water (College Station: Texas A&M University Press, 2009), 21

12Rocio Guenther,“Espada Aqueduct: A Centuries-Old Link to the Spanish Colonial Missions,”

Rivard Report, 8 Sept. 2017, therivardreport.com/espada-aqueduct-a-centuries-old-link-to-the-spanish-colonial-missions/.

13Charles R Porter, Spanish Water, Anglo Water (College Station: Texas A&M University Press, 2009), 32 

14Charles R Porter, Spanish Water, Anglo Water (College Station: Texas A&M University Press, 2009), 32

15Charles R Porter, Spanish Water, Anglo Water (College Station: Texas A&M University Press, 2009), 32

16“Acequias,” The City of San Antonio - Official City Website, City of San Antonio , 2 March

2018, www.sanantonio.gov/Mission-Trails/Mission-Trails-Historic-Sites/Detail

Page/ArtMID/16185/ArticleID/4230/Acequias?ID=53.

17“Acequias,” The City of San Antonio - Official City Website, City of San Antonio , 2 March

2018, www.sanantonio.gov/Mission-Trails/Mission-Trails-Historic-Sites/Detail

Page/ArtMID/16185/ArticleID/4230/Acequias?ID=53.

18“Acequias,” The City of San Antonio - Official City Website, City of San Antonio , 2 March

2018, www.sanantonio.gov/Mission-Trails/Mission-Trails-Historic-Sites/Detail

Page/ArtMID/16185/ArticleID/4230/Acequias?ID=53.

19Rocio Guenther,“Espada Aqueduct: A Centuries-Old Link to the Spanish Colonial Missions,”

Rivard Report, 8 Sept. 2017, therivardreport.com/espada-aqueduct-a-centuries-old-link-to-the-spanish-colonial-missions/.

20Charles R Porter, Spanish Water, Anglo Water (College Station: Texas A&M University Press, 2009), 36.

21Charles R Porter, Spanish Water, Anglo Water (College Station: Texas A&M University Press, 2009), 36.

22Charles R Porter, Spanish Water, Anglo Water (College Station: Texas A&M University Press, 2009), 38.

23“Mission Espada (Mission San Francisco De La Espada),” The City of San Antonio – Official City Website, City of San Antonio, 3 March 2018, www.sanantonio.gov/Mission-Trails/Mission-Trails-Historic-Sites/Detail-Page/ArtMID/16185/ArticleID/4461/Mission-Espada-Mission-San-Francisco-de-la-Espada?ID.

24Rocio Guenther,“Espada Aqueduct: A Centuries-Old Link to the Spanish Colonial Missions,”

Rivard Report, 8 Sept. 2017, therivardreport.com/espada-aqueduct-a-centuries-old-link-to-the-spanish-colonial-missions/.

25“Acequias,” The City of San Antonio - Official City Website, City of San Antonio , 2 March

2018, www.sanantonio.gov/Mission-Trails/Mission-Trails-Historic-Sites/Detail

Page/ArtMID/16185/ArticleID/4230/Acequias?ID=53.

26Charles R Porter, Spanish Water, Anglo Water (College Station: Texas A&M University Press, 2009), 38. 

27Gazda, Natalie. “Aqueduct Plaque.” 2018. JPEG file.