Emilio López Zamora dam

The Emilio López Zamora dam, also known as the Ensenada dam, is a dam with a water treatment plant in Ensenada, Baja California, Mexico, on the basin of the Ensenada stream. Its main use is the containment of flash floods, and as a water supply for the city. It was built in 1976 and is administered by Mexico's National Water Commission [es] (CONAGUA).

Emilio Lopez Zamora dam
The dam in December 2019, with the spillway open
Emilio López Zamora dam is located in Baja California
Emilio López Zamora dam
Location of Emilio Lopez Zamora dam in Baja California
LocationEnsenada, Baja California, Mexico
Coordinates31°53′24″N 116°36′09″W / 31.89000°N 116.60250°W / 31.89000; -116.60250
Opening date1976
Owner(s)National Water Commission
Dam and spillways
Height34 m (112 ft)
Length200 m (656 ft)
Reservoir
Total capacity3,750,000 m3 (3,040 acre⋅ft)

Characteristics edit

 
Reservoir (2019)

The dam has a reservoir capacity of about 3.75 million cubic meters. However, the useful capacity is estimated to be about 2.61 million cubic meters, since the bottom has filled with mud and debris.[1] The area of the reservoir is 54 hectares. The dam is a concrete gravity dam with a length of 200 meters and a maximum height of 34 meters. The width of the crest is 8.5 meters. It has a drop spillway with a maximum drain rate of 30 meters cubic per second.[2]

Below the dam, there is a water treatment plant with a capacity of 150 liters per second. It takes water from the reservoir and treats it to drinking level to be sent to the distribution network with a pumping system.[3]

Operation edit

The Emilio Lopez Zamora dam is operated by Mexico's National Water Commission.[4][5] In 2018 preventive maintenance was carried out on the dam with an investment of 2 million pesos.[6]

History edit

Built in 1976, it was named for hydraulic engineer Emilio Lopez Zamora, who was the Director of Agriculture in Baja California. The purpose of the dam was to contain flash floods from the local streams and surface runoff, and to supply water to the city.[7]

In 1993 an area of 72 hectares was expropriated from the nearby Adolfo Ruiz Cortines community to be part of the reservoir.[8]

Problems and risks edit

Drought edit

The contribution from the dam to the water supply is sporadic, because of the irregularity of the Ensenada stream.[9] The dam has reached very low levels of accumulated water, due to poor rainfall during long drought periods, as occurred in 2014,[10] with the dam becoming almost empty in 2015.[11]

Overflow risk edit

The dam has reached its maximum capacity and activated the spillway on several occasions, most recently in 2019.[1] During the intense rainfall of March 4, 1978, (86 millimetres (3.4 in) in 24 hours), there was an overflow scare and sandbags were placed at the top of the crest.[2]

There is uncertainty among the nearby population concerning a potential overflow, with the risks balanced by the fact that the dam did not overflow during the intense rains of 1978, and since then there have not been similar rainfall levels.[12]

The real risk of overflowing is increased when the reservoir partially fills with sand and mud due to the lack of dredging.[13]

Garbage and pollution edit

The dam has been illegally used for dumping raw sewage. This situation has worsened due to the population increase in the neighboring communities,[7] including irregular settlements,[14] and with a construction company reported for illegal spilling.[15] On the surface and the edges, garbage and litter, such as plastic bags and bottles, is visible.[16]

Suicides edit

In previous years, people have committed suicide by jumping from the dam, until fences were installed to prevent access.[17]

Other community uses edit

 
The dam in October 2020

The dam also serves as a vehicular and pedestrian bridge.[7]

In the 2002 the Ensenada city council declared the reservoir and surrounding area as an ecological reserve, and in 2007 it was determined to be a protected zone.[18] Plans have been introduced to create a park around the dam[7] or a series of parks from the dam to the ocean following the stream.[19]

The reservoir has been used as a training site for competitive kayaking and boating.[20]

Flora and fauna edit

Vegetation edit

The vegetation around the dam consists of, in order to distance to the water, marsh (next to the water) with species such as Spartina foliosa and Sarcocornia pacifica; coastal sage scrub, and in the higher areas away from the water coniferous forest type trees such as pines, junipers, and calocedrus.[21]

Fish edit

Different fish species have been documented in the reservoir, including exotic species such as threadfin shad (Dorosoma petenense), channel catfish (Ictalurus punctatus), western mosquito fish (Gambusia affinis), bluegill (Lepomis macrochirus), largemouth bass (Micropterus salmoides), and redbelly tilapia (Tilapia zillii).[22]

See also edit

References edit

  1. ^ a b Lachica, Francisco (2019-02-22). "Presa Emilio López Zamora llegó a su máxima capacidad". Síntesis TV (in Spanish). Archived from the original on 2020-06-23. Retrieved 2020-06-23.
  2. ^ a b Vargas, Elizabeth (7 March 2014). "El día que la presa se iba a desbordar". ensenada.net. Archived from the original on 2020-06-23. Retrieved 2020-06-23.
  3. ^ Cruz Tijerina, Néstor (2015-07-09). "¿Por qué no tenemos agua en Ensenada?". 4 vientos (in Spanish). Archived from the original on 2020-06-23. Retrieved 2020-06-23.
  4. ^ "EnsenadaHoy.com - Mantienen presa en buen estado". ensenadahoy.com. 27 September 2018. Archived from the original on 2020-06-23. Retrieved 2020-06-23.
  5. ^ Blancas, Rafael (2015-12-17). "CONAGUA da mantenimiento a presas en Tecate Tijuana y Ensenada". plex (in Spanish). Archived from the original on 2020-06-23. Retrieved 2020-06-23.
  6. ^ Vargas, Elizabeth (26 September 2018). "Realizaron mantenimiento a Presa Emilio López Zamora". ensenada.net. Archived from the original on 2020-06-23. Retrieved 2020-06-23.
  7. ^ a b c d "La presa Emilio López Zamora - El Vigía". www.elvigia.net (in Spanish). 10 August 2011. Archived from the original on 2020-06-23. Retrieved 2020-06-23.
  8. ^ "DOF - Diario Oficial de la Federación". Diario Oficial de la Federación. 20 August 1993. Archived from the original on 2020-06-23. Retrieved 2020-06-23.
  9. ^ "Programa Regional de Desarrollo Urbano, Turístico, y Ecológico del Corredor Costero Tijuana Rosarito Ensenada" (PDF). Secretaría de Infraestuctura, Desarrollo Urbano, y Reordenación Territorial (in Spanish). Gobierno de Baja California. 16 November 2001. Archived from the original (PDF) on 23 June 2020. Retrieved 23 June 2020.
  10. ^ Lamas, Lorena (2014-02-21). "Se acabó el agua de la presa Emilio L. Zamora en Ensenada". Agua.org.mx. Archived from the original on 2020-06-23. Retrieved 2020-06-23.
  11. ^ "Se agotó el agua en la presa de Ensenada". ZETA - Libre como el viento (in Spanish). 18 August 2015. Retrieved 2020-06-23.
  12. ^ Cruz, Bertha Amalia Serrato de la; Gastelum, Alejandro Garcia; Beltran, Carlos Figueroa; Cebada, Dinorah Pantle (2016-04-05). "Percepción del riesgo de inundación por desbordamiento de presa en zona urbana vulnerable". Papeles de Geografía (62): 77–89. doi:10.6018/geografia/2016/234741. ISSN 1989-4627. Retrieved 2020-06-05.
  13. ^ Sánchez, Gerardo (2015-07-17). "Ensenada: Exigen a la Conagua desazolvar la presa". Agua.org.mx. Archived from the original on 2020-06-23. Retrieved 2020-06-23.
  14. ^ Lamas, Lorena (2022-03-14). "Presa de Ensenada, grave foco de contaminación". Zeta. Archived from the original on 2022-04-01. Retrieved 2022-04-01.
  15. ^ Lamas, Lorena (2015-02-17). "Contamina Casas Geo presa de Ensenada con aguas negras". La Jornada Baja California (in Spanish). Archived from the original on 2020-06-23. Retrieved 2020-06-23.
  16. ^ Lachica, Francisco (2019-02-07). "Denuncia equipo de canotaje de BC en la presa Emilio López Zamora". Síntesis TV (in Spanish). Archived from the original on 2020-06-23. Retrieved 2020-06-23.
  17. ^ Vargas, Elizabeth (10 May 2010). "Se suicidó lanzándose a la Presa en Ensenada". ensenada.net. Archived from the original on 2020-06-23. Retrieved 2020-06-23.
  18. ^ "Localización de la Industria en Ensenada, PDUCPE y Fortalecimiento Institucional". Instituto Metropolitano de Investigación y Planeación de Ensenada, Baja California. 2008. Retrieved 3 June 2020.
  19. ^ "Proponen "parque lineal" a lo largo del Arroyo Ensenada". hiptex conectando historias. 22 September 2018. Retrieved 2020-06-23.
  20. ^ Zepeda, Alejandro (2012-12-24). "Historias 2012: Ana Isabel, de la Presa López Zamora al Mundial". AGP Deportes (in Spanish). Archived from the original on 2020-06-23. Retrieved 2020-06-23.
  21. ^ Santos, Ana; García, Jonatan (3 May 2018). "Santuario para el cuidado y la conservación del agua, Ensenada B.C." (in Spanish). Queretaro, Mexico: Escuela de Diseño, Arte y Arquitectura, ITESM. Archived from the original on 21 June 2020. Retrieved 21 June 2020.
  22. ^ Ruiz-Campos, Gorgonio; Contreras-Balderas, Salvador; Andreu-Soler, Asunción; Varela-Romero, Alejandro; Campos, Ernesto (February 2012). "An annotated distributional checklist of exotic freshwater fishes from the Baja California Peninsula, Mexico" (PDF). Revista Mexicana de Biodiversidad. 83 (1): 216–234. doi:10.22201/ib.20078706e.2012.1.751. Archived from the original (PDF) on 2020-06-23. Retrieved 23 June 2020.