Segura Hydrographic Confederation

Segura Hydrographic Confederation
Pza. Fontes, 1
30001 Murcia
Tel.: 34 968 35 88 90
Fax: 34 968 21 18 45

See other water plans


Water Law 29/85:

Water is a scarce natural resource essential for life and for the exercise of the vast majority of economic activities.

Surface water and groundwater, nature and role identity, are renewed by the hydrological cycle and should be available not only in quantity but also necessary to precise quality.

Demand for water planning and forecasting future conditions and situations, so as to minimize the socio-economic costs of resource availability and establish an equitable allocation of the workload.


The water plan should: get the best satisfaction of water demands and to balance and harmonize regional and sectorial development, increasing the availability of the resource, protecting its quality, saving their jobs and streamlining its use, in harmony with the environment and other natural resources.

Hydrological planning
General economic planning
Territorial planningEnvironmental planningEnergy planningLand planning
Urban and industrial developmentConservation of natureEnergy efficiency plansImprovement and modernization of irrigation
Supply and sanitationEnvironmental flowsRenewable energyNew irrigation schemes

Contents of the River Basin Management Plans

Art. 40 Water Law

  • inventory of water resources
  • uses and demands
  • priority criteria and compatibility of uses
  • allocation and resource reservation
  • the basic characteristics of the water quality
  • the basic rules on irrigation improvement and transformation
  • protection zones for the conservation and resource recovery
  • plans hydrological-forestry and soil conservation
  • guidelines for groundwater recharge and protection of aquifers
  • basic infrastructure
  • criteria for evaluating the energy use
  • studies and actions to prevent flood damage, floods and other water phenomena

Historical background

  • The national water works, 1902
  • 1887 defense plan
  • The national water works in 1933.
  • Segura basin, the hydrological imbalance, transfer to the Segura, the left channel and right bank. Irrigating 125,000 hectares
  • Comprehensive use of the upper basin (1941)
  • Hydroelectric header. Harmonization with the irrigation
  • The decree of 1953
  • Allocation of volumes to Las Vegas. The surplus resources.
  • The Tajo Segura
  • Redotación and expansion of irrigation

General description


Andalucía1.780 Km2
Castilla - La Mancha4.713 Km2
Región de Murcia11.150 Km2
Comun. Valenciana1.227 Km2


Andalucía17.424 hab.
Castilla - La Mancha65.927 hab.
Región de Murcia1.032.275 hab.
Comun. Valenciana197.597 hab.


Temperature (range of variation)10-18ºC
Maximun temperature45ºC
Pluviometry (range of variation)200-1000 mm
Average pluviometry365 mmm
Potential evapotranspiration (range of variation)600-950 mm
Average potential evapotranspiration827 mm

Land use

Other arable land30%
Other arable land26%

Resource allocation

Decree of 1953
 a) Approach (Trad. + Legal + Nuevos)b) Actual values
Total (HA)Average strength (m3/Ha)Total Volume (Hm3)Total (Ha)Average strength (m3/Ha)Total Volume (Hm3)
High zone16.0007.10011313.4547.629102
Medium zone18.0008.26014811.0907.75486
Low zone25.0008.26020627.2976.562179
Surplus (Mula, Lorca y Cartagena)0066009
Leftovers (RLMI)00000~=30
First phase of water transfer (Ley 52/1980)
For irrigationHm3
Vega Alta y Media del Segura65
Regadíos de MUla del Segura8
Lorca y Valle del Guadalentin65
R. de Levante, M.I. y M.D. V. Baja del Segura y Saladares de Alicante125
Campo de Cartagena122
Total regadíos400
Para abastecimiento urbano110
(*) Pérdidas (15%)90

(*) By agreement of the Central Board for the Exploitation of the Tajo-Segura, the figure is 10% (60Hm3) in view of studies and data from the first years of operation of the Aqueduct.

Irrigated areas

Estimated areasR. Compl. TrasvasesTotal
Vegas Segura y otras zonas regables superficiales0102.421
    Nuevos regadíos052.482

See map

Water resources

Previous estimatesYearHm3
P:N:O: Hidraúlicas C. segura1933860 (sólo río Segura)
Centro de Estudios Hidrográficos1967950 (Sólo rio Segura)
Doc. Básica Plan Hidrol. Cuenca19921.000 (Total cuenca)



Drain the sea R. Segura: -50

Drain the sea R. Costera: -30

Evaporation of dams and aquifers: -60

Renewable total: 860


First phase ATS: 600

Losses: -60





OTHER (Backish water): 35

Allocation of new resources


o Overexploited aquifers

o Irrigated package


Supply, industry and services


Key actionsMillions of pesetas
Reform and modernization of irrigation 
Primary network61.182
Secundary network120.220
Post-transfer Tajo-Segura 
Irrigated areas14.532
Infrastructure improvement and replacement7.930
System management 
Improved regulation and distribution27.771
Infrastructure exploitation of aquifers in drought period2.262

Defenses and channeling

Key actions:

  • Flood control
  • Ramblas conditioning
  • Defenses and channeling
  • Rio Segura better targeted

Sanitation and depuration

Invest (Millions of pesetas

  • Andalucía: 389
  • Castilla-La Mancha: 4.600
  • Región de Murcia: 43.000
  • Comunidad Valenciana: 5.192
  • State: 39.054
  • Total: 92.235

See map



  • Rice: 1
  • Crypto-wetlands: 12
  • Freshwater pond: 28
  • Salted pond: 4
  • Dams or weirs: 23
  • Coastal wetlands: 17
  • Lagoons: 25
  • Interior salt marshes : 8

See map



JumpsPower KwEfficiency GwhAmount (millions of pesetas)
1. Fuensanta5.00017600
2. Cenajo(*)5.000331.400
3. Fontanar52.0001006.500
4. Talave-Cenajo11.000662.200

(*)Regardless Talave-Cenajo connection

Water quality


FeaturesQuality group limits
Suspended solids(mg/l)<30<70<120
Settleable materials (ml/l)<0.5<1<1
DBO5 (mg/l)<15<30<60
DQO (mg/l)<80<120<300
Dissolved oxygen (mg/l)<5>3>1
Detergents (mg/l de lauril sulfato)<2>3<6
Manganese (mg/l)<0.05<0.4<0.4
Lead (mg/l)<0.10<0.5<0.5
Cyanides (mg/l de Cn-)<0.01<0.1<0.1
Chlorides (mg/l de Cl-)<250<400<700
Sulfates (mg/l de SO4 -2)<200<400<800
Sulfides (mg/l)<1<1<2
Sulfites (mg/l)<1<1<2
Fluorides (mg/l de F-)<1.5<10<10
Total phosphorus (mg/l de P2O5)<5<10<20
Ammonia(mg/l de NH +4)<0.5<1<1
Nitrites (mg/l de NO -2)<50<100<150
Nitrates (mg/l de NO -3)<100<200<300
Oils / fats no persistent(mg/l)negativoindiciosindicios
Phenols (mg/l de C6 O14 H6)<0.001<0.002<0.05
Aldehydes (mg/l)<1<1<2
List I substancesexentasexentasexentas
Pesticides (mg/l)<0.05<0.05<0.05

Programme and regulation

Accompanying Programs

The various actions contemplated in the Segura Water Plan are included in the following programs Accompaniment:

     Water Control and Public Consumption Regulations Sec
     Control and Water Use Regulations Sec Recreativo
     Promoting social use of reservoirs
     Retrieve. and ordenac. margins and banks
     Demarcation of D.P.H. and areas of police
     Plans Hidrológ.-Forest and preserves. soil
     Delineation of flood zones
     INFRASTRUCTURE. and Syst. Management forecasting and flood defense
     Improvement, modernization and consolidation of irrigation
     Hydroelectric Development
     Eutrophication of water bodies
     Determination of environmental flow
     Identification of sensitive areas
     Improvement of hydrological knowledge
     Supplies., Desalination, wastewater treatment and reuse
     Control Networks
     underground water
     Dam safety
     Monitoring and Control Plan

According to the purposes to be achieved, different actions are subsumed under the following objectives:

     Increased water resources
     Drainage and water treatment
     Flood Defence
     Improvements and environmental protection
     Improved irrigation
     Hydroelectric equipment state infrastructure
     Control networks and other inland waters
     Research and development
     Replacement and maintenance

Investment by objetives

ObjetivesPercentage distribution (%)
 AmountCentral AdministrationAutonomic AdministrationLocal AdministrationTotal
Increased water resources31.8596.4006.4
Drainage and water treatment92.2357.910.7018.6
Flood Defence65.62313.30013.3
Improvement and environmental protection65.8957.92.82.613.3
Improved irrigation195.93411.727.9039.6
Hydropower equipment12.3002.5002.5
Control Networks15.5323.1003.1
Research and development8.0351.6001.6
Replacement and maintenance7.9301.6001.6


Investment by finantial agents

Central Administration277.27156
Autonomic administration204.92941.4
C.A. Valenciana55.33411.2
C.A. Castilla - La Mancha27.4155.6
C.A. Andaluza6920.1
Local Administration13.1442.6


Regulations I

  • Criteria for Priority Uses:

    1. Supply of populations, including small industries connected to the grid
    2. Irrigation and agricultural uses
    3. Industrial uses other than electricity production
    4. Industrial uses for electricity production
    5. Acuiculture
    6. Recreation
    7. Other uses
  • Demands and guarantees

    To satisfy the demands, the guarantee to be provided by the operating system will be based on the concept of accumulated deficits, adopting as standares values​​:

    • Supplying: 10, 16 y 30%.
    • Irrigated lands: 50, 75 and 100% of annual demands set by the sum of deficits in one, two and ten consecutive years respectively.
  • Package:
    1. Urban demand. Not be accepted in the long term value of losses in the networks of over 2% or gross appropriations in liters / capita day, greater than:
      Permanent populationUpperMediumLow
      Less than 10,000280250220
      10,000 to 50,000310280250
      from 50,000 to 250,000360330300
      More than 250.000410380350
    2. Agricultural demand. Not be accepted in the long term, the effects of the Water Planning unit gross values ​​of strength, in / ha. year, exceed:
      Field Crops6.300
      Forage crops12.200
      Woody crops8.300

Regulations II

  • Flow rates and volumes required for environmental reasons:

    Establishes the goal of sustaining a minimum flow to certain environmental and health effects of 4 m3/sec., Circulating from Contraparada (Murcia) to San Antonio Dam (Guardamar).

    This flow may be derived from previous uses returns as inputs or desembalsando specifically programmed for this purpose.

    For the upper reaches and tributaries of the Segura generally set a minimum flow in permanent channels, equivalent to 10% of the average annual contribution in natural regime. (Unless otherwise justified).
  • Allocation and reservation of the resources available to today's demands:

    Is withheld for the state of any possible appeal not assigned according to the provisions of RD Law 3 / 86 to December 30.

    If so enables P.H. National will tend to improve environmental minimum flows to subsequently eliminate overexploitation of aquifers and be balanced to meet the remaining deficit.

    Will proceed to grant all concessions linked to the first phase of the Tajo-Segura, in the areas of activity covered by the Law 52/80.
  • On concessions and review:

    Exceptions justified given the situation of water shortage in the basin will not be awarded concessions for new uses in that it does not prove the availability of renewable resources for their care.

    Generally not be granted concessions of groundwater with the possible exception of the high seats, depressed areas or aquifers in which new concessions can not significantly affect the rest of the operating system of the basin. These concessions must obey the exceptional social interest and its granting is not required to provide significant conditions to third parties.

    The review of the granting concessional flows to adapt its actual needs will be evaluated based on the provisions in the Plan, the flow actually derived and the characteristics of the existing infrastructure.

    From the date of approval of the Plan shall update the inventory of all existing exploitation in order to know the actual characteristics of them and their administrative proceeding generally to the installation of meters or other measuring instrument . This facility will be mandatory for supplies and industrial uses and in other cases when the volume is over 100,000 m3/year.