Tagus-Segura Water Transfer
Tagus-Segura Water Transfer | |
---|---|
Begins | Province of Guadalajara, Spain |
Ends | Province of Albacete |
Official name | Trasvase Tajo-Segura |
Maintained by | Government of Spain |
Characteristics | |
Total length | 286 km (178 mi) |
History | |
Construction start | 1969[1] |
Opened | 1979 |
The Tagus-Segura Water Transfer (
History
Although it was mentioned as early as 1902, the origin of the transfer system dates back to 1932, when the
The transfer system project was resumed through the
Course
The Tagus-Segura Water Transfer links the Bolarque Reservoir on the Tagus River (40°21′41″N 2°49′14″W / 40.3613°N 2.8205°W) with the Talave Reservoir on the Segura (38°31′10″N 1°54′00″W / 38.5195°N 1.9001°W). It is 292 kilometers (181 miles) in length and has a flow rate of 33 cubic meters per second (1,200 cubic feet per second). The transfer's structure comprises four sections:[3]
Section I includes the ascent at Altomira, a key piece in explaining the energy efficiency of the transfer system. It permits water from the Bolarque Reservoir at 636 meters (2,087 feet) to be pumped through two metallic pipes up to the Bujeda Reservoir in the Sierra de Altomira, a 245 m (804 ft) rise in elevation. This task is accomplished by the reversible pumped-storage plant Bolarque II, which relies on four vertical generator assemblies with their corresponding Francis pump-turbines, capable of pumping 66 m3/s (2,300 cu ft/s). The Bolarque-Bujeda system was designed to pump an anticipated 1,000,000,000 m3 (810,000 acre-feet) per year.
Section II connects the Bujeda Reservoir to the
Section III joins the Alarcón Reservoir to the Talave Tunnel.
Section IV is for the most part formed by the Talave Tunnel's length of 32 km (20 mi), which runs at varying depths between 150 m (490 ft) and 320 m (1,050 ft). The course then emerges into the Talave Canal, which leads at last to the Talave Reservoir on the Mundo River, a tributary of the Segura.
Regulation
Law 21/2013[4] introduced major changes to the Tagus-Segura Water Transfer's regulation policy. These changes, while maintaining the source basin's precedence and respecting the specifications of its resource planning, are meant to improve system management by establishing a set of impartial technical standards to eliminate previous insecurities and to provide objective, straightforward criteria for operation.
Water is dispensed into the transfer system on a monthly basis, depending on the total water supply available in the reservoirs of Entrepeñas and Buendía at the beginning of every month. Four levels are used to specify the distribution volume for each transfer, with a maximum annual total of 650,000,000 m3 (530,000 acre⋅ft) per water year (600,000,000 (490,000) for the Segura and 50,000,000 (41,000) for the Guadiana).[5]
Level 1. When the total water supply in Entrepeñas and Buendía is equal to or greater than 1,300,000,000 m3 (1,100,000 acre⋅ft), or when the total
Level 2. When the total water supply in Entrepeñas and Buendía is less than 1,300,000,000 m3 (1,100,000 acre⋅ft) without reaching the volumes given in Level 3, and the total inflow recorded in the previous twelve months is less than 1,200,000,000 m3 (970,000 acre⋅ft), the relevant agency shall authorize a transfer of 38,000,000 m3 (31,000 acre⋅ft), not exceeding the yearly maximum.
Level 3. Assigned when the total water supply in Entrepeñas and Buendía does not exceed, at the beginning of the month, the values shown in the following table:
Oct. | Nov. | Dec. | Jan. | Feb. | Mar. | Apr. | May | Jun. | Jul. | Aug. | Sep. | |
---|---|---|---|---|---|---|---|---|---|---|---|---|
m3 x 106 | 613 | 609 | 605 | 602 | 597 | 591 | 586 | 645 | 673 | 688 | 661 | 631 |
acre-feet | 497,000 | 494,000 | 490,000 | 488,000 | 484,000 | 479,000 | 475,000 | 523,000 | 546,000 | 558,000 | 536,000 | 512,000 |
At this level, which constitutes an irregular hydrological situation, the relevant agency shall authorize at its discretion and with valid justification a transference of up to 20,000,000 m3 (16,000 acre⋅ft).
Level 4. When the total water supply in Entrepeñas and Buendía is less than 400,000,000 m3 (320,000 acre⋅ft), no transference is permitted. In order for the reservoir supply to reach this new minimum figure from the one previously fixed at 240,000,000 m3 (190,000 acre⋅ft), a five-year transitional program will be implemented.
To promote the development of riverside communities, priority will be given to the headwater reservoirs for the holding of authorized transfers pending distribution, before the intermediate and terminal basins, as long as this practice conforms to a reasonable and cohesive use of the whole system.
Except in duly confirmed cases of catastrophe or extreme need that disrupt the transfer of water, if the approved volumes outlined in Levels 1 and 2 have not been transferred within the authorized time period, they may still be sent within the three months following the deadline, unless a level change occurs.
Resources authorized for transfer may be used throughout the water year. If any transferred water remains in the receiving basin after the end of the water year, it will be redistributed as an available resource for use in the transfer system during the following water year.
Authorized transfers will be divided between water supply and irrigation, in a 25% to 75% proportion respectively, always assuring at least 7,500,000 m3 (6,100 acre⋅ft) per month for urban water supply.
The Central Commission for Exploitation of the Tajo-Segura will be responsible for authorizing transfers when the conditions for Levels 1 and 2 are met, while the ministry with authority concerning water resources, having received the commission's report, will authorize transfers at Level 3.
In regard to Levels 1 and 2, transfer authorization should be granted over six-month terms, while three-month terms are preferred for Level 3 unless the relevant agency should justify the use of different intervals at any level.
Post-transfer system
The Talave Reservoir marks the beginning of the post-transfer system. This is a
The volume of water assigned for agricultural irrigation from the Tagus-Segura Water Transfer is 400,000,000 m3 (320,000 acre⋅ft), approximately 53% for new irrigation plots and the rest for replenishing previously irrigated land. According to mid-2009 concession proceedings, the irrigable zones of the post-transfer system comprise a nominal surface area of 132,724 hectares (327,970 acres), of which 82,257 ha (203,260 acres), or 62%, are located in the Region of Murcia.[7]
The average yearly water volume transferred into the Segura Basin from 1979-2014 was 328,000,000 m3 (266,000 acre⋅ft) per year (55% of the allowed maximum).[8] Volumes transferred for public use have not varied greatly over time, unlike irrigation transfers, whose average yearly sum was 204,000,000 m3 (165,000 acre⋅ft), almost half of the allocated quantity.
According to estimations made by
The official launching of the Tagus-Segura Water Transfer made intensive farming possible in the Spanish southeast, consequently placing the region among the largest European outdoor producers of out-of-season crops. For this reason, it is widely known as the "vegetable garden of Europe."
See also
- Aqueduct (water supply)
- Hydroelectricity
- Water supply and sanitation in Spain
- List of tunnels in Spain
References
- ^ "Historia del Trasvase Tajo-Segura: Aprobación" [History of the Tagus-Segura Transfer: Approval]. Región de Murcia Digital (in Spanish). Retrieved 10 February 2015.
- ^ Soto García, Mariano; Martínez Álvarez, Victoriano; Martín Górriz, Bernardo (2004). "El regadío en la Región de Murcia. Caracterización y análisis mediante indicadores de gestión" [Irrigation in the Region of Murcia: Characterization and Analysis through Performance Indicators] (PDF) (in Spanish). Sindicato Central de Regantes del Acueducto Tajo-Segura. p. 38. Retrieved 10 February 2015.
- Ministry of Agriculture, Food and Environment. Retrieved 10 February 2015.
- ^ "Ley 21/2013, de 9 de diciembre, de evaluación ambiental" [Law 21/2013, on December 9, for Environmental Evaluation] (PDF) (in Spanish). 11 December 2013. Retrieved 10 February 2015.
- ^ "Real Decreto 773/2014, de 12 de septiembre" [Royal Decree 773/2014, on September 12] (PDF) (in Spanish). 13 September 2014. Retrieved 10 February 2015.
- ^ "Tagus-Segura Distribution Canals: Distribution Canals, General Outline". Ministry of Agriculture, Food and Environment. Retrieved 10 February 2015.
- ISBN 978-84-8371-462-1.
- ^ Soto García, Mariano (14 November 2014). "Principales referencias del Trasvase Tajo-Segura relacionadas con el regadío" [Principal References for the Tagus-Segura Transfer Concerning Irrigation]. El regadío (blog) (in Spanish). Retrieved 10 February 2015.
- ^ "Impacto económico del trasvase Tajo-Segura" [Economic Impact of the Tagus-Segura Transfer] (PDF) (in Spanish). PwC (PricewaterhouseCoopers). 2013. Retrieved 10 February 2015.
- ^ San Martín González, Enrique (2011). "VI.1.1. La polémica durante los primeros pasos del trasvase" [The Controversy During the First Stages of the Transfer]. Un análisis económico de los trasvases de agua intercuencas: el trasvase tajo-segura [An Economic Analysis of the Interbasin Water Transfer Systems: the Tagus-Segura Transfer] (PDF) (Doctoral thesis). Universidad Nacional de Educación A Distancia. Retrieved 10 February 2015 – via Fundación Aquae.
- OCLC 733880671.
Treinta años después de iniciada la explotación del Acueducto Tajo-Segura, resulta díficil de entender que su funcionamiento todavía no se haya normalizado y que todavía se siga cuestionando el suministro de agua.