Home > Members > ICID Directory >

Eng.Goncalo de Freitas Leal
General Director, DGADR
Portuguese National Committee on
Irrigation and Drainage (PNCID)
Av Afonso Costa, No. 3
1949-002 Lisboa, 600082440

Tel : +351 218 442 200
Fax : +351 218 442 202
Email : geral@dgadr.pt
Website : http://www.dgadr.pt


Eng. Goncalo de Freitas Leal
General Director, DGADR
Portuguese National Committee on Irrigation and Drainage (PNCID)
Address as above


Prof. Dr. Luis Santos Pereira
Vice President Hon., ICID
International Commission on Agricultural Engineering (CIGR)
Departamento de Engenharia Rural
Instituto Superior de Agronomia
Universidade Tecnica de Lisboa
Tapada da Ajuda, 1349-017 Lisboa

Tel : +351 21 365 3480, +351 21 365 3400, +351 21 365 3339
Fax : +351 21 362 1575
Email : lspereira@isa.utl.pt


Mr. Pedro Eduardo da Cunha Serra
c/o Portuguese National Committee on
Irrigation and Drainage (PNCID)

Email : aderito@inag.pt

Member - ERWG

Directory Contents..


A. Physiology and its People


Portugal is one of the oldest countries in Europe and the world, founded in 1143 whose identity is well established for centuries. The area of Portugal is 92075 km2, including the mainland, Continental Portugal, with an area of 88944 km2 (including the area of estuaries permanently covered by water), and two insular regions, Madeira, 79 km2 and Azores, 2337 km2. The total population of both the areas is 2488100 inhabitants, or 26.6% of the population of Continental Portugal. The current borders of Continental Portugal were established by the Alcañices Treaty, between the Kingdoms of Portugal and Castilla, in 1297. The Portuguese possession of the insular territories is recognized since the 15th century.

The Portuguese mainland is located between the latitudes of 37ºN and 42ºN in the Western part of Europe, subject to the influence of the Atlantic Ocean which washes the Western and Southern coasts and it is also affected by the Mediterranean in the Southern region of the country.


Portugal is a cultural and political unit, having a common religion and language in all the territory, Portuguese. The political administration lies in a Central Government and two Regional Governments, one for each insular territory. The capital is Lisbon.


Portugal&&146;s resident population was estimated (31st December 1997) at 9 957270, 95% of whom live on the mainland. The mainland population was scattered over the country&&146;s 88,944 km2 somewhat unevenly: overall population density was 106.5 inhabitants/km2 and the figures for each of the 7 Agricultural Regions varied between a minimum of 19.8 inhab./km2 in the South to 337.6 inhab./km2 in the North. The area with the highest density of population is the Lisbon Metropolitan Area, located in the North Bank of Tejo Estuary, which comprises the municipalities of Amadora, Cascais, Lisboa, Loures, Oeiras, Sintra and Vila Franca de Xira, with an area of 1057 km2, the total population of 1847700, and a population density of 1748. The Setúbal Península Area, adjacent to Lisbon is located on the South Bank of Tejo Estuary, having an area of 1521 km2, a population of 640400, and the population density of 421.


There has been some improvement in the level of education of agricultural producers with a greater percentage of producers today having formal education (ranging from basic to higher education), rising from 54% in 1989 to 60% in 1995.


The majority of agricultural producers live mainly on income derived from activities outside the farm (66%), which has not been affected by the reduction in the number of agricultural production units.


B. Climate


Portugal has two climatic regions: the region influenced by the Atlantic sea, and the region having a typical Continental clime. The Massif regions also have an important meaning in the Portuguese climatic context (DEVEAU et al., 1985). The mean annual temperature varies between 7ºC in the hills of the interior central region to 18ºC on the South coast. The mean monthly temperature on the Portuguese mainland records a maximum high in July and August (21.8ºC) and a minimum low in January (8.8ºC). The highest mean monthly values for maximum air temperature are observed in the Northern and Central interior regions and in the &&147;Alentejo&&148; region during the months of July and August when temperatures exceed 30º C. The lowest mean monthly values for minimum air temperature occur in the hills of Central interior region in the months of December, January and February and register approximately -1ºC.

The rainfall on the Portuguese mainland varies greatly in space and in time. The lowest mean annual rainfall (<600mm) occurs in the South-east (interior &&147;Alentejo&&148;) and in a small area of the North-east (part of &&147;Trás-os-Montes&&148;). Mean annual rainfall values greater than 1500 mm occur on the coast in the North of the country and in the hills of interior regions of the North and Centre.


The mean annual rainfall is about 920 mm in Continental Portugal having a non-uniform spatial distribution more concentrated on the Minho hydrographic region where the corresponding value practically duplicates the average for the Continental Portugal whereas values for Guadiana, Sado/Mira and Algarve hydrographic regions are significantly lower (about 63% to 64% of the average for Continental Portugal as a whole). Average rainfall distribution in the year is markedly non-uniform: about 75% to 80% of the mean annual rainfall which concentrate in the six wet months, from October to March.


C. Agriculture


The Utilized Agricultural Area (UAA) in Continental Portugal decreased by 2% between 1989 and 1995, mainly due to a reduction in arable land.


There has been a significant increase in the area devoted to fodder cultivation and temporary grassland (+ 4.6%). The increase verified in the area of permanent pasture during this period (+25.2%) is of relative importance considering that the relevant Community definition allows areas of questionable suitability for agricultural use to be included in this group as poor quality pasture. Amongst other possible reasons, the reduction in area of various types of crops is the result of a decrease in the number of farms (-25.2%) which, in turn, may be mainly due to :

  • farms taken over by others;
  • land left abandoned;
  • suspension of an activity with the result that a farm holding no longer meets the minimum requirements to be considered as such.

Over the last decades, the development of public irrigation projects in Portugal has been closely and predominantly associated with six crops or groups of crops: rice, tomatoes, corn, pasture, vegetable and fruit and, more recently, sunflower. In fact, despite the motivations and production objectives associated with the majority of the areas irrigated are based on the development of specific activities (pasture, tobacco, beetroot, tropical fruit, etc.). It is seen that, in practice, the crops which showed greatest growth in each area were those which, over the time, produced the best economic results for the farmers. In 1989/90 there were 625829 hectares of irrigated UAA, wherein 115003 hectares corresponded to individual irrigation projects while 157 869 hectares were assorted.


D. Water Resources


The main control of water resource management is assigned to the Ministry of Environment (MA), which comprises central and regional departments. The agricultural control is assigned to the Ministry of Agriculture, Rural Development and Fisheries, which comprises central and regional departments.


The main functions of other different bodies of the public administration are divided in two different components, viz. normative actions, planning, management, licensing of activities, and supervision, control and inspection. The rainfall, stream flow and water quality networks are operated by the Institute of Water.


Hydrographic Regions


Portugal and Spain share five international river basins of rivers Minho, Lima, Douro, Tejo and Guadiana.
For assessing the water resources, a territory division was adopted through a compromise between the topographic divides demarking the main river basins and the administrative boundaries of the municipalities. Hydrographic regions were thus established that comprised the main river basins of Continental Portugal.


Surface flow


Given the small number of gauging stations or the lack of homogeneity in several of the available series of records, owing to changes in the natural flow regime produced by human factors, the surface flow contributions are derived from relations between annual values of surface flow and the amount of rainfall in the gauged river basins.


The mean annual flow for Continental Portugal is 407 mm, or about 44% of the value of mean annual rainfall. The differences in flow characteristics clearly show the non-uniform nature of the spatial flow distribution. The variability of the flow annual distribution is significant.




The geology of a given region is the physical factor that governs the infiltration and circulation of underground waters. From the water resources viewpoint, and in a sustainable development framework, it is not possible to extract water from an aquifer more than the water recharged into the aquifer to ensure that the aquifer does not get exhausted.

Nevertheless, in extreme situations like drought, abstraction may exceed recharge of an aquifer provided that in an average rainfall or wet years, the aquifer is fully recharged.


Overall groundwater availability is estimated at 5.94 million m3 corresponding with a uniform equivalent depth of 67mm. This value works out to about 60% of the mean recharge of the aquifers. The spatial distribution of the groundwater availability is markedly non-uniform in relative terms, Estremadura and Vouga are the richest regions, comprising a significant part of the western Meso-Cenozoic Border, followed by that of Tejo that covers part of the aquifers of the Tejo and Sado Cenoantropozoic Basin. The Guadiana hydrographic region is the poorest in terms of groundwater availability &&150; only 29 mm.


Irrigation and Water Use


All hydrographic regions have surplus water resources during average conditions, but low regulation due to lack of reservoir sites can lead to localised problems of maintaining water supplies during dry conditions, particularly in the Guadiana, Sado/Mira and Algarve regions. The Alqueva, Odeleite - Beliche and Odelouca - Funcho projects thus highlight these water resource problems in southern Portugal.


There are no records of evapo-transpiration to identify the distribution of this variable. Thus, the evapo-transpiration is calculated by methods that relate to hydro-meteorological variables recorded in meteorological stations. The available calculation methods make it possible to calculate potential or reference evapo-transpiration. The reference evapo-transpiration was calculated by the Penman method. The actual evapo&&151;transpiration is calculated on basis of the reference evapo-transpiration and rainfall, by the water balance method.


The total water demand is estimated at 10 849 hm3/year. The distribution by water use category is shown in Table 1. (These values are based on estimates supplied by INAG in March 1996).


Table 1. Present Water Use in Portugal

Water Use hm3
Domestic and Public Supply
Irrigated Agriculture


The useable resources are estimated to be approximately 12 910 hm3, including return flows. Of these, approximately 4270 hm3 are from Spain. (These are preliminary estimates provided by INAG). The agricultural sector utilises the largest amount of water, accounting for approximately 79% of the water demand. The largest agricultural demands occur in the Tejo, Douro, Mondego and Sado regions. The demand for this water is concentrated in the driest period of the year. Regulated water resources are provided by more than hundred large dams. Agriculture is the main user sector of water resources.


Domestic and public water supply is below the European average in terms of per capita demand and the proportion of the population served by piped water supplies.


The Continental Portugal features are dominantly Mediterranean with rainy winters followed by hot and dry summers in which the majority of crops are highly conditioned by the surplus water in the winter and its insufficiency during the dry period. The inhabitants of the country are most affected by this situation although several irrigation and drainage projects have been carried out, which allowed them the benefit in a more rational way, from the available natural resources. This situation was more evident in the North of the country not only because of the scantiness of arable soils prompting farmers to use more land which has not only been possible with the introduction of irrigation, but also because of the greater demographic density and the availability of a great number of waterways. Thus, private and traditional irrigation projects emerged and spread all over the country, first along the waterways in order to make the most from alluvial soils, and afterwards, a little all over the place including the exploration of groundwater.


Up to the year 1995, 88 264 hectares of irrigation projects were created by public initiative amounting an increase of 14621 hectares between 1995 and 1999. In relation to the drainage projects, 1996 saw the construction of 67902 hectares of drainage works. However, some works were expected to complete by 1999 to benefit 6200 hectares in the Central region (river Tejo) and 12000 hectares in the Northern region (river Vouga).


A total irrigated area in Portugal was 625829 (1998) of which 115003 was covered by collective farming, 352759 by individuals and 157869 ha was composed by other categories.


Portugal and ICID


Portugal joined the ICID in the year 1954 and has ever since actively participated in the activities of ICID. Mr. J.F.Rebelo Pinto (1962-65) and Dr. L.S. Pereira (1987-90) were past Vice Presidents of ICID. The Portuguese National Committee is actively represented in ICID workbodies.


Portuguese National Committee hosted 2nd European Regional Conference in 1964.



Directory Contents


© 2016 | ICID | 48 Nyaya Marg, Chanakyapuri, New Delhi - 110021, India
Tel : 91-11-26116837, 91-11-26115679; Fax : 91-11-26115962, E-mail: icid@icid.org [ICID Map]

Follow ICID on: | Facebook| YouTube| LinkedIn| SlideShare