FOOD AND AGRICULTURE ORGANIZATION
OF THE UNITED NATIONS
NATIONAL STUDY ON THE IRRIGATION OF DATE
PALM AND ASSOCIATED CROPS IN TUNISIA
By Dr.LEBDI Fethi
LEBDI Fethi – INAT 1
National Study on the Irrigation of Date Palm
And Associated Crops in Tunisia
FAO - Cairo
This survey is interested in the date palm sector and in particular, to the analysis
of water use and irrigation practice. It is about developing the sector potentialities
and constraints towards water, actors and related systems to date palm.
Perspectives of its development or a better efficiency are summarized at the end
in terms of recommendations.
To approach this survey it will be necessary to characterize this material system.
It is obvious that the existence of oases and the use of water in the desert
surroundings put this material system whose date palm is the symbol and the
illustration that characterize. It is about an agricultural system getting its
properties of a context at a same time:
- Geographic: the oasis is an islet in an arid environment
- Bioclimatic: it is a microclimate created by the man in arid environment
- Agronomic: it is an agro-system intensified to stacked crops
- Socio-economic: it is a shape of settlement and various economic and socio-
cultural activities, in a desert environment.
1 - Oases characterization
a. Geographic and Water resources : Oases have been developed in a
traditional or modern way in the desert zones and have been in continuous
extension because of water mobilization resource possibilities in (forage modern
techniques and exhume, tasks of getting back streamed waters, dams if the site
exists). The traditional oases have been established from easily mobilizable
water resources and not requesting for a lot of energy.
b. Waters appropriation and sharing systems are governed by the customary
management rules and a social code related to the organization of the society in
place. The modern techniques of catchment, forage and storage of water
permitted to increase the available resources for irrigation. Unfortunately, these
resources are difficulty renewable and a loss of the artesianism is operated with
the progression of water exploitation. The main oases of the South of Tunisia
belong to 4 distinct regions: Jerid, Nefzaoua, Gafsa and Gabes. They are
separated by large desert extents. In the world, North Africa, the Arabic
peninsula or Asia are the main geographical zones of date palm existence.
LEBDI Fethi – INAT 2
c. Bioclimatic: date palm develops in a microclimate created by the man in arid
environment and induced by crops terracing. The aridity climate is the common
point to the set of oasien systems, but its features vary from a zone to the other,
according to parameters (continentally, topography, wind). The South Tunisian
climate is desertic, modified by the neighborhood to the sea. This modification is
sensible to Gabes, on the coast, where monthly temperatures of May until
October, are lower and cause less favorable conditions to the development of the
best varieties of dates. This report is the same to Gafsa, except that the region is
continental and in height in relation to Jerid and Nefzaoua regions, what eases
again the summer. It is in the Jerid and the Nefzaoua that one encounters best
conditions to the date palm crop. The bioclimatic characteristics led to an oases
i. Coastal oases: characterized by a soft winter where only the date
palm common varieties are cultivated. The palm tree importance is
secondary in relation to incomes procured by the other crops (market
crops (example of Henna and salad that are exported) and under
greenhouse shelters, arboriculture as the example of the pomegranate
tree in oases of Gabes, also exported).
ii. Altitude oases: Characterized by one cool winter. Essentially
situated in the region of Gafsa and the one of Tameghza, in these
oases, date palm is not as important as in the Jerid or the region of
Nefzaoua. Arboriculture (fig-tree, grapevine) and the market crops
have a major position. Date palm however remains the main frame,
necessary to the establishment of the oases ecosystem.
iii. Continental oases: essentially localized in the Jerid (Tozeur,
Nefta, Degache) and Nefzaoua (Kebili, Douz,…) and lately in Rjim
Maatoug. Date palm and Deglet Ennour variety are the main crops in
these oases. These oases contain 85% of the total palm trees strength
of the country and contribute to 90% of Date national production. With
the date palm and in layer, varied arbor crop exists, market crops and
fodder crops productions, especially the Alfalfa. This last exists mainly
because of the presence of the ovine raising.
d. Agronomic: The oases environment conceals a rich genetic diversity material
and adapted to particular soil conditions (salt, aridity). Crops associated to date
palm are numerous (arboriculture, vegetables, fodder crops or local crops with
high economic value as “Henné”). The animal production constitutes an
important factor for the oasis economic and ecological balance. The presence of
fodders species and legumes, manure produced by animals, are necessary to
the maintenance of the soil fertility and the improvement of their physical and
chemical characteristics. Raising products (milk, meat) contribute not only to the
improvement of populations nutritional state, but also to the improvement of their
LEBDI Fethi – INAT 3
sources of incomes, by the introduction of artisanal activity (hairs, wools, skins
and leathers) built-in in an oasis tourist space.
c. Socioeconomic: The oasis agricultural system and populations that live there
reacted to the technological contributions and to a market economy. Parallel
activities and generated by the date production and the development of oases
saw the day, in particular, the handicraft, the tourism, the oasis products
transformation the or dates, the merchandising and the conditioning.
2 - Actualized statistics on Date palm
Figures actualized on date palm (Onagri, 2006) permit to take out again the
- Oases estimated surface in the governorates of Gafsa, Gabes, Tozeur and
Kebili is 32980 ha, of which 15350 ha traditional oases.
- The trees number for the season 2005-2006 is 4,539 millions of which 2,827
millions of Deglet Ennour (62.3%).
- About 77.7% of productive date palm and the remainder is a young plantation
or a very old, non productive.
- Dates raw production for the season 2005-2006 is about 133320 tons, of which
83660 tons of Deglet Ennour.
The distribution of date palm occupied surfaces, by region, for this same period
Table 1: Date palms surface distribution in Ha (Onagri:2006)
Surface in Ha Traditionnel Modern Total surface
Tozeur 3370 4850 8220 25%
Kebili 4220 11780 16000 48%
Gafsa 820 1000 1820 6%
Gabès 6940 - 6940 21%
15350 17630 32980
This table shows especially that the region of Nefzaoua (kebili) arranges a big
potential, either nearly the half of the available surface for date palm, with the
particularity that more of 70% are modern and therefore recent and that implied a
big mobilization of new water resources. But in terms of quality, the Jerid
(Tozeur) and The Nefzaoua constitutes the fief of the main variety Deglet
LEBDI Fethi – INAT 4
The Distribution of date palms number, for the season 2005-2006, indicates that
among 4,539 millions of date palms 3,528 millions are currently productive:
Table 2: Distribution of the number of date palms (ONAGRI: 2006)
Number % Cropping Intensity%
Tozeur 1.609.000 35,4 % 157
Kebili 2.282.000 50,3 % 150
Gafsa 178.000 3,9 % 155
Gabès 470.000 10,4 % 189
The extension of Deglet Ennour cultivated surfaces in Kebili was the origin of an
intense exploitation of the underground resources and the multiplication of
forages and wells, sometimes illicit. The raw water consumption, by hectare
passes 10000 m3, from where a water economy program introduced and
reinforced to decrease these consumptions. Tozeur Oases remain among the
oldest and some parallel activities have been developed around date palm and
3 - Cultural considerations
The practice of intensive oasis agriculture requires some specific natural
- Fertile earth, sometimes rare in arid environment. The contribution in
manures and in natural fertilizing is essential, from where the importance of the
raising association with oases;
- Irrigation operation well distributed in the time, taking account of physical
chemical characteristic of the soil, the other crop association and water
competition with date palm and different crop needs.
- Soil without hydromorphy, cleansed. This question is to the agenda in
certain oases and is associated, in addition of soil features, to the irrigation
Date palm grows better when fertilization is adapted to the chemical features of
soil and water used for the irrigation, in presence. The main mineral contributions
are nitrogen, but in mastered quantities because it influences on the quality of the
fruit, the phosphate, potash and the manganese for certain Tunisian poor oases
of this element. It is sometimes useless to bring these mineral elements if they
LEBDI Fethi – INAT 5
exist in irrigation water with sufficient quantities. Nevertheless, it is necessary to
take account of associated crops (arboriculture and especially Alfalfa).
The association of organic manure, where its contribution is judged necessary by
agriculturists, with chemical manures cannot give meaningful results, outside of
the effect on these associated crops. On the other hand the organic manure is
used on the whole of oases: farm manure (result especially of the ovine raising),
compost (residues of harvests, straws, bad herbs) and green manures (cultivated
legume between date palms and buried before the flowering step: Alfalfa), that is
in competition with the herd food.
b - Pollination:
Date palm is a “dioic” plant, where male or female flowers are carried by two
different trees: sexes are separated. Male palms " dokkars " have the same
importance that those that give fruits. Deglet Ennour male palm is selected and is
multiplied (has even some in vitro tests) because some " dokkars " have a direct
interest on the forwardness, the quality or the quantity of produced pollens.
These pollens have an impact on the fruition rate and dates quality.
Agriculturists consider that two " dokkars " are necessary by hectare of palms to
assure a good pollination. The female and male palm flowering must be
synchronous. It is for this reason that the male palms are installed in the same
cultural conditions that the female palms. Agriculturists harvest male
inflorescences after their bursting and make them dry safe from the sun, in dry
environment, in order to pull the pollen from epilates operation. Of this fact, a
male inflorescence market has been developed, but the exhibition in the sun
compromises the germination power of their pollen. Extractors of pollen from the
male inflorescences are finalized to automate this operation and to avoid the
alteration of the produced pollen. In the same way, mechanical pollinators by
hand permit currently a mechanized pollination.
c - Preventive struggle, bio product:
Date palms devastators are developed and get acclimatized in this biotope,
favorable also to the date palm development: Mites (“Goubar”) which feed
themselves of fruits, cochineals that cause big damages on the young
plantations, “pyral” dates are a part of devastators, susceptible to touch date
palms. The setting up of a specialized research center in oases (center of
Degache), of a prevention and biologic struggle choice services permitted to
eradicate a certain number of illnesses and to make dates a biologic product,
healthy and demanded on the international markets, in the middle of a certain
number of requiring rules in quality.
LEBDI Fethi – INAT 6
d - Climatic and water effects
However, the climatic or water effects can be at the origin of physiological or non
- Temperature and frost: date palm supports an important temperature gradient
but until a certain limit. It can be developed between 7°C (zero of vegetation) and
45°C (hopeless vegetative activity). Its optimum of vegetative activity is located
between 32 and 38°C. Nevertheless, one defines a thermal indication called
"fruition heat", which corresponds to the sum of the mean daily temperatures
going from flowering to the maturation. In North Africa this indication is defined
on a period of 200 days for Deglet Ennour, and one admits that 1000°C
constitute the sum of temperatures limit for the crop of date palm. For what
concerns frost it is tolerated by the plant for a limited period, otherwise this
provokes the drying up of palms. Deglet Ennour variety is very appreciable to
- Humidity: It directly acts on the harvest and on the propagation of illnesses.
Dates are soft when the humidity is strong and dry when it is weak. Wind hot and
dry «chhili» accelerate the ripeness of dates and provoke the desiccation of
fruits. The management of irrigations takes account of this phenomenon,
especially for Deglet Ennour case, identified like a half - soft date. Some
windbreak is conceived to protect the palm trees and to master movements of
dunes, as well against sandy winds and the drainage effect of wind.
- Rain: It is especially beneficial by its role of leaching, because the soils and
water saltiness constitute the major constraint in Tunisia. But rain has a harmful
effect in the spring and can drag the pollen, or at the harvest time, generating a
deterioration of fruits. Consequently, the program of cover date regimes, with
nets or bags in polyethylene, has been initiated. This program had for
consequences that since 2001 all the oasis of the Nefzaoua uses this technique,
that advanced of some days the dates ripeness because of an increase of the
temperature and the limitation of the pyrale illnesses.
- Water stress and saltiness: important variations of the humidity in soil
(shortage or excess) provoke a disruption of the vegetative cycle of the date
palm. The production decreases and can even disappear:
A water stress due to a deficit in needs satisfaction in water, that continues,
provokes a vegetative slowing and a yellowness of foliages. According to the
intensity of water stress and its length the production decreases and this can be
going until to provoke the drying up of the palm. The oasis can disappear. The
availability of the resource in water is a condition to the existence and the
everlastingness of the oasis. It was not the case, otherwise in the very isolated
LEBDI Fethi – INAT 7
oases, of extremely weak dimension (some trees) and that don't have any
economic interest, even for their owners, whose main work is elsewhere.
- The excess of water and the saltiness are very frequent stress factors in
Tunisia, by the nature of soils, the quality of water irrigation or frankly of practices
and techniques of irrigation employed. This is much more shaded when there is a
close watertable at a little deep. The lack of maintenance of the drainage and
leaching network of the soil, if it exists, drag the raising of the level of the
watertable and by capillary ascents, the soil salinity in roots zone and at different
levels in the profile and even the deposit of salts in surface. Asphyxia of roots is
generated and some irreversible damages can take place, succeeding to the
withering of palms. It is especially the case of some old oases that are covered
currently by a rehabilitation program, financed by the state.
4 - Associated crops: competition and complementarities
Date palm is the main frame of an oasis. Nevertheless, crops in layer come to be
added to palms, with an arboreal layer and a market crop layer (typical three-
layer cropping system in oasis. The highest is dates palm and second is
pomegranate and fig tree. One the surface, fodder crop/vegetables is planted).
This isolated ecosystem, completely dependent of mobilized water resources for
the irrigation is capable, on a limited space, where the water economy constitutes
the major constraint, to make possible a varied and intensive agricultural
situation, with a very high valorization of water and soil, a discriminating and
lasting compromise between the present crops, creating a complementarities
situation (fodder crops are a source of fertilization and cohabit with the palm in
good conditions) and the water competition at the same time (species that
cohabit in association with date palm have neither the same needs nor the same
tolerances as this last), but also allowing the agriculturist to vary his sources of
a - Windbreak: the necessary installation of windbreaks to the periphery of the
oasis protects against the advanced of dunes and against the drying up of crops,
but drags a competition for water. Nevertheless, the windbreak consumption in
water is partially compensated by the ETP reduction.
b - Fruit arboriculture: the olive tree, the pomegranate tree, the fig-tree and the
grapevine are the main trees constituting the first layer of crop, under date palm.
Between the two, the competition is located to different levels: space, lighting,
soil and water. The frequent installation mode of fruit trees is very well in
intercalated space between palms, either in regular plantation underlying. The
installation mode of an orchard inside stitches of palms is rare. Tests of
avocados or banana trees remain limited and without hopeless effect on the
market. The competition between the fruit trees and date palm is again a topic
that a number of researchers compete to clarify it and to quantify it, for an optimal
LEBDI Fethi – INAT 8
management of water resource and soil resource through the brought
c - The competition depends on soil slices exploited preferentially by roots, on
the humid horizons. Date palm possesses a roots system which develops in the
lateral direction, to depths going from 40cm to 1m20, with bursts toward the
watertable. The regularly irrigated fruit trees and without deficit develop their
roots in surface. But the frequency and the satisfaction degree of water needs in
soil horizons influence the penetration degree in the roots soil. This implies that
the irrigation technique and the irrigation management mode by the agriculturist
as well as the efficiency of the water application to the parcel permit a good or
bad cohabitation of the two layers cropping pattern. The knowledge, not even
obvious, of the specific needs in water and in nutriments of every crop layer
permits then a fruitful cohabitation. This permits productions display during the
year (from the spring to the fall for the fruit trees and at the end of the fall for
dates). Products are valued on markets because they are precocious and often
of biologic quality.
d - Fodders Crops: these crops include mainly legumes and the Alfalfa, which is
everlasting. They are used as green manures and foods for the domestic raising.
The Alfalfa develops a deep roots system as that date of the palm tree and
because of this fact, competitor of this last for water. The Alfalfa being covered
by the palm, its ETP is more reduced. There again, this reduction coefficient of
the ETP regionalized of covered crops is again a topic between hands of
researchers and engineers, but the experience in oases remain more tributary of
the water availability that of the potential needs of plants, to deduct some of the
convenient lessons from the empiricism and the experience.
e - Market crops and rental crops: the most widespread market gardeners are
more caused by a domestic need (pimento, tomato, green salad) and a small
market of the village. On the other hand, some oases are specialized in pension
crops, like the Henna of Gabes or some tests of the saffron.
5 - Economic considerations
The cultivated surface cannot inform to it alone on the importance of date palm in
the agricultural space of the country. Indeed, the present plantation density
counts among the most important in the world, with the other countries of the
Maghreb (around 200 palms by hectare), behind Somalia that reached more than
500 palm by hectare, but with the varieties a lot less valued that Deglet Ennour.
A rehabilitation program of oases has been undertaken since the years 1990,
concerning the extraction and the replacement of secondary economically
varieties and other old palms.
LEBDI Fethi – INAT 9
Outputs are variable according to years. Surfaces and secondary economically
or common variety productions (El Alig for example) regressed since years 1980.
The total of date productions is 46800 Tons for the season 1980/81, of which
20000 Tons of Deglet Ennour and 26800 Tons of common dates varieties.
The evolution of these productions in the time is clear, thanks to rehabilitation
programs of oasis and to the economic value of Deglet Ennour variety. The
production of the season 2005/06 is 113000Tons, of which 70000 Tons of Deglet
Ennour and solely 43000 Tons of common date varieties. Exports in quantities
passed of 28.3% of the total production in 1981 to 43.62% in 2005.
The productivity by hectare varies according to years, even from a region to the
other (between the Jerid and the Nefzaoua), but is located on average inter -
yearly around 4.5 Tons/Ha. Because of the possible incomes to the hectare
(around 10000Dt), even though properties in oases are small, they can be
profitable when the exploitation is domestic, what is often the case.
Nevertheless, the fragmentation of properties (inheritance, sale) obliged
authorities to resort to a program of fundamental rehabilitation (in progress in the
month of January 2007 on 650 Ha of the old oasis of Tozeur that will be spread
to Nefta and Degaches oases. This will facilitate the planning inside the oasis
(tracks, networks) and a management more efficient of economically viable
exploitations, without ecologically disfiguring of the oasien system.
Economically, the date’s sector constitutes the main financial resource for
populations of cities and villages around oases. Indeed, the sector contributes for
4.34% of the raw value of the agricultural productions (year 2001) and for 15.7%
of the value of agricultural product export. This sector occupies the third place in
the agricultural export scale, after oil and sea products sectors.
On a world scale Tunisia occupies the twelfth place in terms of productions in
Tons, pass to the third position in terms of export in Tons and stand first in terms
of export in monetary values. Europe and Morocco are the principal importing of
During the year 2005/06, the quantity of exported dates is about 42 770 tons, that
is to say 38% of the total production, what brought to the state 131 millions of
dinars ' 1 $is around 1.3Dt). The main Tunisian export destination is countries of
the, at the rate of more of 90%. The main importing European Union countries:
France, Italy, Spain and Germany; these countries export a part of quantities
already exported by Tunisia.
LEBDI Fethi – INAT 10
Production and export evolution
Exported dates values evolution
This commercial aggressiveness was the fruit of a number of parallel actions,
which contributed sometimes to conquer new markets (Asia, Europe of the East),
i. Techniques of date cover by nets, permitting to give a better appearance
of the fruit and its protection at the time of rainy events;
ii. The biologic protection against illnesses and predators;
iii. Texts of laws protecting the oasis or the import of products which can
transport or can harm to date palms;
iv. Modern techniques of packing and conditioning;
v. The alignment on the international rules and norms for what are the agro
alimentary products and the traceability. This has been reinforced by
stamps assigned in particular to Deglet Ennour;
LEBDI Fethi – INAT 11
vi. The setting up of formation infrastructures, research and popularization for
vii. The installation of agriculturist sons on new oasis creations;
viii. The intervention of the state for the subsidy of all these actions and its
Essentially, dates remain biologic products, very valued by a market spread
outside of the arid zones.
6 - Conditioning
The conditioning constitutes the final stage of the date treatment, for what
answer to requirements of the market. Dates are routed in cases or in regimes,
toward storage and conditioning units. An operation of sorting of good dates and
incompletely mature or rotting dates precedes the storage operation. The sorting
is very important to extract the stock destined to the export, according to the pre-
definite norms by the destination market. This sorting is made in a semi-
mechanical manner with the help of tables with mobile rolling strip. A
housekeeping operation is achieved to remove spots on the date skin and
decontamination is also done, by exhibition to the heat (what kills all bugs).
The storage is assured in stores provided of ventilation and ventilation devices.
These stores are treated by insecticides and rat poison. The conditioned and
wrapped dates in cases with different sizes, sometimes with regimes, permit the
expedition in all markets of the world. The present number of date conditioning
units is 34, of which some are in the North of the country. A control quality of
products is introduced, from samplings appropriated on production lines.
7 - Traceability
The European regimentation (regulation THIS 178/2002) on foods security
imposes the setting up of a traceability adapted to the restraint of products for all
food commodities. With regard to dates in Tunisia the Professional Grouping of
Fruits hired a national action in order to conform to this guideline and then
European regimentation. The production and merchandising chain of dates
includes besides agriculturists, one coins path of collectors, wholesale and
retailing, more one coins path of export. The led actions concern:
- Identification and the codification of production zones (oasis)
- Identification and the codification of date collectors
- Identification and the codification of date conditioners
8 - Parallel economic sectors to oases
The transformation of dates is oriented more toward the confectioner sector.
Number of actions is achieved:
LEBDI Fethi – INAT 12
- the diversification of productions from dates:
o dates dough
o dates flours
o covered dates
o coated dates
- the transformation:
o syrup of dates
- the use of garbage:
o dates sugar
o livestock food
o compost preparation
Besides, the oasis as an ecosystem led to intense artisanal and tourist activities.
Products of palms, the ovine raising or the presence of dromedaries led to the
artisanal creations, in particular for what is dresses (wool, skin) or to the other
tools (traditional baskets, …etc).
The same oasien ecosystem was to the origin of the most intense tourist activity
in the country. Hotels chains increased, museums of popular arts and history of
the desert, the organized trailers and incursions in the desert, ski on dunes,
…etc., generated work and permitted to the region to develop its infrastructures
(roads, airports), to vary sources of incomes and show a profit to the best
agriculture of oases, of which the system inside and its durability has not been
touched, since the parallel economic activities happen to the oasis peripheries.
LEBDI Fethi – INAT 13
1 - Irrigation practice history in oases
Tunisian Oases had inspired since the beginning of the century, scientists of all
side, in particular a physiologist attached to the «Bureau of Plant Industry» of the
United State Department Agriculture. Mr. T.H.Kearney had visited, at beginning
of the century in 1903, in the Tunisian Jerid, to study the local date palm varieties
there and to obtain plantations corresponding to the best varieties, in order to
tempt the crop in the United States. A collection of 97 samples has been sent in
a first stage and 700 plants were added again to the collection, following this
action. In the month of October 1905, 95% of imported date palms from Tunisia
were on the right track resumption in Arizona and California plantations. Some
comparative studies followed then, between the Jerid, the Nefzaoua in Tunisia
and Phoenix in Arizona and Volcano Springs in California. They concerned the
climate and irrigation techniques, to situate agro climatic characteristics and the
technical packet which is suitable with the production of quality dates.
In the region of Nefzaoua and from 1907, the 3 water sources (Kebili-Ras El Aïn
with 100l/s, Mansourah and Taouergha with 60l/s) not being sufficient anymore
to extensions of oases, artesian well forages were undertaken and new oases
are created, at the same time as the older ones received a water complement
supply. In 1957, at the dawn of the independence of the country, it counted
75000 date palms, irrigated from the source of Ras El Aïn, with 100l/s. Currently,
and in 2006, the number of palms evolved toward 2.282.000, either a report of
30, thanks to a big program of water resource mobilization.
The distribution of water is made in Gadous (an ellipsoid that marks a length of
five minutes: 18 Gadous correspond to let sink water during one hour and half),
in the same seguias. In the beginning of the 19th century the same water rights
are respected, to the satisfaction of the population in place. In the same way,
creation tentative of artesian wells on the one hand increased the debit available
to the irrigation, but had a negative impact on the under pressure watertable
“artesianism” and water sources.
In 1914, at the time of a forage in Telmine, in the region of Nefzaoua, it appeared
for the first time that in 24 hours, the creation of the poll entailed oases wells
drainage, menacing the disappearance of palm trees, whose the poll was not
destined to them. Again today, the multiplication of forages and the exploration of
deep watertables, made disappear skinny water sources comparison with the
new extensions and demands in water, real transfers of populations operated
themselves, regroupings in irrigators associations saw the day to better fear the
available debit management.
In the Jerid region the sharing of waters has been established by " Ibn Chabat ",
imam and known historian, death at the end of the 13th century. Tozeur oued,
LEBDI Fethi – INAT 14
the meeting of all sources of «Ras El Aïoun», produced about 700l/s, dividing in
three branches and every branch in seven seguias. The seguia, last fairway of
water distribution, and managed in the time. The tour of water is of one week,
sufficient for water needs and for the management of an easily usable reservoir,
corresponding to a light soil rather sandy. The irrigation in peak time is 24/24h,
either of the rising to the rising according to the sun. The day is fixed thus:
- obvious sun rising and setting
- the five main prayers (" fejr: the dawn ", " Dhohr : 13h ", " asr : around 16h ", "
maghreb : sunset ", " Acha : toward 20h ")
- the " Helloul el Bab " or opening of the door of the old Tozeur, that takes place
one hour and quarter before the sunrise
- human shade lengths measured in feet, and connected to the period the day.
All these hourly references that govern the irrigation are based on the sun,
prayers and the economic activities between the prayer, according to rights of
water and a distribution table. The " Gadous " corrects the hourly space
inequality based on the march of the sun, while alternating water allocations
between the day and the night (an owner receives water during the day on one
week and during the night the week after), what brings back the hydraulic service
to a water tower and a supplied volume. Agriculturists lend to each others
Gadous, freely from a water rotation to the other one.
A particularity of oases regions in Tunisia, reside in the fact that the water volume
allocated to every parcel is independent from the surface of this last, because it
is a vested right, independent of the soil property. More again, in certain cases,
the property of the tree (called " Habous ") can be distinct of the one of the land
(the owner can dedicate lines of date palms to one human and caritative action
illustrated by “saints " with their " zaouiat " or mausoleum). There are then three
properties: this of the soil, of the water and of the tree. In fact, this is not water
that is attached to soil but it is well the opposite that is true (it was permitted to
use its right of water where one wanted).
The date palm irrigation, through a “seguia” network with a free surface and
irrigation by basins or by boards was achieved in winter as in summer (weekly).
This water need in winter is generated by a need of salt leaching and drainage, in
addition of the water irrigation in summer. What makes that water needs of date
palms integrate the own needs of the tree and those of the soil leaching.
The impact of the progressive soils salinity, following irrigations can be ominous
in the absence of an efficient drainage and irrigations practice, under the
constraint of an imposed water tower and a fixed allocated volume. The state
manages to distribute the system until the secondary network.
2 - Exported water balance (physical and economic Balance)
LEBDI Fethi – INAT 15
The water quota of the Tunisian in the year 2004 is 417m3/an/habitant. Only, the
standard of living of the medium Tunisian let suppose that the water quota to its
disposition is from afar more important. Indeed, if one considers water resources
physically existing in the country, this quota would be located to the quoted value
previously cited. But if one considers his comfort and his hygiene level, there is
there a balance to make, not in terms of water volumes physically existing, but in
terms of exported and imported agricultural products that required the water
factor for their production.
The objective is to proceed to a conversion of the agricultural production in the
dates sector, in equivalent of water volume used and exported, according to the
statistics chronology from 1984 to 2006, then to make a comparative balance of it
with the oil sector, in order to situate its position in the export of water for two
crops with a big added value in the country.
The adopted method is based on taking in consideration the outside trade
numbers of the agricultural products descended of irrigation and to a very high
added value. Indeed, olive oil and dates, in addition to the sea products are the
first three export products in Tunisia of. A comparison, in units of m3water as
value of the exported product, can inform on the real valorisation of the employed
m3 water for the irrigation of these products. At first we listed figures of exported
quantities and their values, during the period 1984-2006 (INS, 2007):
LEBDI Fethi – INAT 16
Table 3 : Exports in Tons
Year Olive oil Dates
1984 75977.0 16206
1985 46215.0 15214
1986 44191.0 14267
1987 56974.0 15764
1988 52161.0 15766
1989 46908.0 16611
1990 49717.0 18031
1991 158166.0 19453
1992 96473.0 17119
1993 122627.0 18510
1994 192909.0 20782
1995 90177.0 20872
1996 28906.6 18216
1997 126026.8 21310
1998 124105.9 27299
1999 163867.0 23099
2000 113863.3 22411
2001 94529.3 47043
2002 22502.2 41890
2003 39875.8 42010
2004 211175.3 40200
2005 109371.3 53217
2006 100000.0 42770
LEBDI Fethi – INAT 17
Graph 3: Dates exports evolution (in Tons)
Evolution des exportations en tonnes des Dattes
Graph 4 : Olive oil exports evolution (in Tons)
Table 4: Exports in values (x1000 Dt)
LEBDI Fethi – INAT 18
Olive oil Dates
1996 117095.9 46654.2
1997 288449.8 52101.0
1998 212669.2 70076.5
1999 382741.1 56294.4
2000 263899.2 52759.3
2001 200269.9 105618.3
2002 55763.8 97447.3
2003 114349.3 95196.6
2004 707972.9 106000.0
2005 476690.3 137000.0
2006 623000.0 131000.0
Graph 5: Exports Evolution in values (x1000Dt)
1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006
On the basis of yearly average needs in water of 6000m3/ha for the irrigated
olive tree and of 12000m3/ha for date palm (using the improved surface irrigation
technique, that reduced all flights between the water source and the board or the
basin, inside the parcel. This demand in water expresses the water application
efficiency by the agriculturist). The mean outputs are 10tons/ha for the olive tree
and 12 tons/ha for date palm. One can dice at the time to deduct an evaluation of
the equivalent in volume of consumed water, corresponding to quantities of
products exported. For that, one uses agricultural output data (T/Ha), as well as
their consumption in irrigation water (m3/Ha) to get the equivalent in m3/T:
LEBDI Fethi – INAT 19
Table 5: Valorization of one m3 of water
Water needs Yields T/ha Equivalent in m3/T
12000 (Improved 12 1000
Dates surface irrigation)
Olives 6000 10 600
Olive oil 6000 2 3000
Don’t forget: (1Ton of olive oil is given by 5 tons in mean of olives)
From these figures of exported quantities and from won values it is possible to
roughly estimate quantities of exported water through products (dates and olive
oil) and the monetary value won by this action of irrigation:
Table 6: Export of m3 water through the exported products
(Units: Millions of m3)
Olive oil Dates
1984 228.0 16.2
1985 138.7 15.2
1986 132.6 14.3
1987 171.0 15.8
1988 156.5 15.8
1989 140.7 16.6
1990 149.2 18.0
1991 474.5 19.4
1992 289.5 17.1
1993 367.9 18.5
1994 578.7 20.8
1995 270.5 20.9
1996 86.7 18.2/
1997 378.1 21.3
1998 372.3 27.3
1999 491.6 23.1
2000 341.6 22.4
2001 283.6 47.1
2002 67.5 41.9
2003 119.6 42.1
2004 633.5 40.2
2005 328.1 53.2
2006 300.0 42.7
LEBDI Fethi – INAT 20
Table 7: Valorization of the exported m3 of water (Dt)
1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006
Olive 1,35 0,76 0,57 0,78 0,77 0,70 0,82 0,95 1,12 1,45 2,076
Dates 2,56 2,44 2,56 2,44 2,35 2,24 2,33 2,26 2,64 2,57 3,062
Graph 6 : Valorization of the exported m3 of water (en Dt)
Finally, it is possible to us, to raise a summary balance of previously exposed
results. The exam of the achieved work above that exported water quantities
through products of high added value, confirm the monetary value of the m3
water and its degree of valorisation, while integrating all the work achieved on the
conquest of markets and their target. If the m3 of water is sold around 0.050Dt, it
brings back for dates more than 2 Dinars, according to years and the fluctuations
of the market and the harvest.
2 - Water management and irrigations practices in oases
a. Water resources
The underground waters form the main resources in available water for the date
palm crop and for oases. Some rare examples of works about spreading overflow
water for weak size oases (example the one on the Tameghza oued) exist. The
underground resources pull in the two aquifer deep of the terminal complex
(depth from 40 to 400m) and of the inset continental (depth from 80 to 2800m).
LEBDI Fethi – INAT 21
Water sources that spring through the geological layers were the first use of the
underground watertable, that are the indication of their existence and that are the
first origin of oases. Forage techniques helping, some deep polls have been
executed and in a big number, in the favour of a big agricultural development in
the pre-Saharian region.
In front of the weakening of sources alimentation debits a reaction in chain has
been started: the source dries up, then the forage loses its “artesianism” and
pass to the pumping.
In Gabès region, it is the watertable of the continental inset localized in the region
of El Hamma and chott el Fejjaj and the Jeffara watertable, in the North of
Gabès. The superficial watertables exist but they are localized. Everywhere, the
piezometry is decreasing and the under pressure watertable “artesianism” gets
In the region of Kebili, the intense exploitation of deep watertables overtook
counselled resources for a yearly exploitation. Water sources disappear and the
“artesianism” doesn't stop decreasing.
The underground waters close to oases are for some important temperature,
encouraging the promotion of projects of geothermal water and precocious crops.
Geothermal Waters can reach more than 60°C; they serve to heat greenhouses
(9/10 of debit) and to irrigate them (1/10 of the debit). The cooled waters and
those served to the nocturnal heating of greenhouses, leave toward the oasis.
The heating tip is in winter, what coincides with a consumption hollow for the
oasis. These waters must be in addition managed in a seasonal way.
The resource in available water becomes a relative notion if one confronts it to
water demands. These are important and turn around 18000m3/ha/an, with a
continuous fictional debit from 0 .5 to 1l/s/ha. The question that is asked
concerns the possibility of an insufficient resource or rather a strictness lack in
the management of this resource. The water economy program initiated by the
State aims to correct this failing.
b - Categories of oasis views of quoted it of water and the irrigation
Taking account of the water resources potential, of the water demand, of the
water allowance in terms of time and spatial distribution, of transit capacities of
the hydraulic networks and pumping, the following categories has been identified
(DG/GR, 2006), knowing that during the year, the confrontation between the
water actually extracted from forages (m3/ha/day) and water needs shows two
periods in the year: an excess period and the other showing a deficit in water.
The deficit in water appears between the half-April and half - September, and
that otherwise, a relative excess of the resource exists:
LEBDI Fethi – INAT 22
- Category 1: where the water excess in the winter is very weak in front of the
deficit in the summer: water extracted from forages overtakes water needs and
this occurs especially during the winter months, when water needs are at the
lowest level. The deficit that is result of the level of resource satisfaction in
available water and needs, especially peak, in summer, being important, this
denotes two facts: the available resource is very weak in relation to needs, even
if we predict a storage in winter in the case of the “artesianism”, in addition of the
transit capacity of the hydraulic network which is very weak (it is the case of
“Mides” oases in “Tozeur”).
- Category 2: where the water excess in winter is weak enough in relation to the
summer deficit: water in excess during the period of the winter is important
enough and it is technically possible to stock it in the “artesianism” case and to
transfer it during the period of the summer, to decrease water deficit effects
during the peak time, according to a seasonal management rule (case of the
Jedida oasis in kebili).
- Category 3: where the water excess in winter is weak but close to the summer
deficit: the water transfer according to a seasonal management rule permits to
cover a good part of the deficit, if the transit capacity of the hydraulic network
permits it. (El Hamma in Tozeur).
- Category 4: the excess in winter and the deficit in summer himself are
equivalent: the same remark as for the category 3, with a total cover of the deficit
of the winter.
- Category 5: the water excess of in winter passes the summer deficit: according
to the water transit capacity of the hydraulic network, one can distinguish oasian
systems able to absorb completely this deficit solely by the transfer of the winter
excess toward the summer and to save quantities in addition of the winter or to
intensify more again crops system.
For every category and according to constraints, either the resource, either
seasonal management rule, either the transit capacity of the hydraulic network, a
particular action can be developed in order to improve the hydraulic service and
the satisfaction of the water demand.
b. Adopted techniques and irrigations management in oases
Until the advent of modern irrigated perimeters, oases constituted the most
elaborate model concerning collective management of water resources and the
transportation infrastructure. Water sources were the focal point of the oasien
installation, with a sharing of the water allocation, relative to a water right that the
most often corresponds to the power that can have a person or a family owner.
Because of this, the transportation infrastructure and the sharing of the water
LEBDI Fethi – INAT 23
allocation (channels in clay, water partition) assures this water allocation until the
parcel. Its maintenance and its upkeep are in the community hands, according to
The parcel is distributed in basins (Houdhs ") and is levelled in the sense of
alimentation “seguias” in water. The network in the parcel is nourished by a
secondary “seguia” drifted from the main “seguia”. The water allocation thus
transported can be important in certain cases (until 45l/s in the Jerid). This debit
will be shared then between one or several tertiary then quaternary “seguias”,
that are going to irrigate basins respectively in crop.
The agriculturist's technicality appears at the level in the efficiency of water
application and its restraint of the discharge living time at the level of the basin as
well as in the planning of this last (size, slope). Practically, the agriculturist tries
to maintain the soil to the capacity to the field, until the next water allocation.
The intensification of crop oasien systems, the extension or the creation of new
oases, the new well forage in the same watertable, gave a new dimension to the
water value, after deficit observation in the satisfaction of water demands.
The agreed important investments for the water mobilization and the setting up of
irrigated perimeters as well as the water rarity, push to a valorisation of this
resource. A complex whole of independent factors conditions the water restraint
and the irrigation performance and its technical efficiency:
the irrigation network and the hydro agricultural amenities nature in the
the nature of soil and its features
used irrigation techniques and their restraint
the perception of water problems economy or water loss by the irrigators
the agrarian and fundamental structures and the impact of the property
partition on the irrigations efficiency.
Actually, every oasis is characterized by a typical combination of these factors,
concerted together to a certain efficiency of the irrigated system. In oases, the
hydraulic efficiency of irrigated systems depends in a large measure of employed
technology. The panoply of irrigation techniques used in Tunisia for oases limits
itself to the following fan:
It is used in all oases, in the parcel (basins, boards). The traditional surface
irrigation is supplanted by the improved surface irrigation thanks to water
economy actions initiated by the state. This technique, when it is not mastered,
can be to the origin of big water losses and weak irrigation efficiencies. Its
restraint passes by a rigorous levelling, an adaptation of head debits to
LEBDI Fethi – INAT 24
measurements of watering units (boards, basins) and a tertiary network
waterproofing in the parcel. Efficiency is the order of 70% for the improved
surface irrigation technique. Otherwise, water losses are relatively important and
efficiency can fall until less 50%. These losses are three types:
Losses by storage in “seguias”
Losses by infiltration and possibly overflow in “seguias”
Losses by deep percolation.
For certain oases, whose irrigation is assured by “seguias” in clay (a big effort
continues in the “seguias” waterproofing), the global loss rate by infiltration and
storage in “seguias” turns around 40% of the delivered volume and the global
loss rate by percolation is valued to 10% of this same delivered volume. These
losses brought back to the acceptable values, would permit to increase brought
volumes if these are insufficient, to improve outputs or to arrange a better
In the same way, the variance between the sent volume at the head of the sector
and the sold volume on this sector can be explained by two factors:
Flow discharges superior to demands: water losses can have as a main
origin at the level of joints flights, between secondary and tertiary channels
elements and at the level of outlet infrastructure that can be closed badly or non
insulated. To compensate these losses the sent debit at the head of the network
is superior to the demand. This debit can reach 20% of the demand.
Otherwise, when the demand is weak, in order to fill more quickly the terminal
branches of channels for the distant islet servicing, a debit superior to the
demand (attack debit) is set free in head during the first instants.
An imprecision of the servicing: typically, the hydraulic network is
- Either, of a source debit or a debit of the water catchments point
- Water is transported, either in the main channels, either in the primary conducts
at low pressure, toward a main water division,
- The debit is then distributed in water allocations, in conducts or secondary
channels, toward a distribution point (boundary-mark low pressure or secondary
- The tertiary network, in channels generally, must permit to route the water
allocation toward the parcel
- The quaternary network, clay or concreted “seguias” is often formed inside the
The state support the management of the system until the secondary network.
LEBDI Fethi – INAT 25
With regard to the localized irrigation, it is not very extended because of limits of
its adaptation to oases of a certain age and consolidated. Nevertheless, several
tests have been achieved, without big success of generalized application.
Water economy built-in program for oases and actions
It is an important and built-in program, achieved for the account of the Tunisian
oases set, at various degrees of realization. It concerns as well alimented oases
by shared water source within a GIC or by well.
In the case of a parcel alimented by a surface well, the water appropriation of is
not collective as well as its management. In this management mode, water
makes integral and non dissociable part of the land that it irrigates. It is the
property of the land that gives, after authorization of the administrative services
of water resources, the access to water.
The private parcels provided of surface well cannot arrange a debit in
continuous, because of the excessive reduction charge of the watertable, that
comes with the pumping (case of Jomna, Kebili). The pumped flows are weak,
variable and depend on watertable potentialities as well as wells density.
Nevertheless, the direct availability of the hydraulic service encouraged the
intensification and the market crop installation.
Because of this, the present situation shows that the use of water economy
techniques is relatively more developed in date palms parcels alimented from
surface wells, than in the remainder of oases confronted to the constraint of the
water allocation. Indeed, operators arrange freely the resource and are more
receptive towards water economy techniques. These perimeters form some
relatively homogeneous wholes to the point of view crop system, predominated
by the fruit arboriculture and the market crops. It is true except in the case of
oases, where the desert environment and oasien results in a very big conscience
of the water question.
The generalized water economy program has for objective:
- To palliate a rate of water loss, since the adduction until the parcel,
- To palliate a rate of loss in the parcel with:
o losses by storage in “seguias”:
o losses by infiltration and possibly by overflow in “seguias”
o losses by deep percolation in basins or boards
This global loss rate can reach 60% of the delivered volume at the head of the
collective network and can add up to millions of m3. This water losses diagnosis
shows that the first origin of the important water allocations resides in water
losses in “seguias” in ground. It is confirmed by values of flight debits (0.11 l/s/m
for the oasis of El Hamma).
LEBDI Fethi – INAT 26
The intensification rate and the occupation rate by weak vegetative cycle crops
(market gardeners, industrial) follows the pace of the water allocation and
disappear if the tour of water doesn't permit their crop anymore (observation from
a 15 days water allocation). In the same way, irrigated parcels by surface wells
undergo the constraint of the weak debit and its availability in continuous.
Possibilities of water economy in oases are real and promising, to seen it of the
various diagnoses achieved in different oases of the four main oasien regions of
Tunisia. The following actions have a direct impact on the economy of water
volumes and the reduction of water deficit, and on the reduction of water
allocations, that can decrease to half, in order to guarantee a viability of weak
- Levelling and waterproofing of all water transportation circuits until the parcel
entry: “seguias” in clay are replaced by “seguias” in concrete (reinforced or no).
The transverse section is oblong (L= 40 x h=25cm).
- “Seguias” inside the parcel can arrange a plastic buried coating to avoid the
rodents and the UVS rays action, if crops don't come to border these “seguias”,
or if the speed of out-flow is strong enough so that it is erosive.
- If the necessary pressure is arranged from the water forage, a collective
network of buried conducts in PVC, provided of boundary-marks in the parcels
entry, can be considered (Case of Douz oasis, Ibn Chabat). The low pressure
network serves terminals, dominating each one a parcel (high point). Inside the
parcel, a gravitating distribution is assured through a network of concreted or
- Levelling of “seguias”: the setting up of proposed solutions for “seguias”
waterproofing will not produce the sought-after effects only if the levelling is done
- Winter market and fodder crops intensification, in view of valorising, the artesian
forages water, in particular.
- Storage of the water surplus coming from artesian forages, in view of inter -
- GICs (: “Groupement d’Intérêt Collectif”: water use association) funding, by the
formation and the framing, in order to master the exploitation of the available
water resource, the administrative and financial management of their business
and the valorisation of the irrigation water.
- The maintenance of the drainage waters and the research of possibilities of
their reuse, without affecting the oasien system durability.
LEBDI Fethi – INAT 27
c. Institutions in charge of the water management
i. Services by the participative management
The management of water, insured at the GIC level, gives systematically right to
the irrigation water, who’s the use is as, that the principle of water allocation is
defined according to the surface to irrigate, to the available debit and the
irrigation network efficiency.
The water right leads to the payment to the GIC, stationary royalties and
consumption royalties, representing a real contribution to the working and
maintenance budget of the hydraulic infrastructures.
Water allocations and doses brought to every watering, especially during
the peak time; vary from a perimeter to another according to the resource
Water losses can mislead water allocations and long enough watering
periods by hectare. In the northern and central perimeters of the country,
water allocations can go until 3 to 7 days in tip and can overtake the 15
days in the southern perimeters.
The brought doses and needs in water are as variable from a perimeter to
another and sometimes it is the available water allocation that sets the
In certain perimeters no yet rehabilitated, water losses misleading an
insufficiency of available debit in the parcel entry or at the plantation level,
result in a weak enhancement rates and important water allocations,
generating a certain system deficiency and sometimes doses not assuring
It is necessary to note that some GICS proceeded to exploitations
planning while endowing them of individual basins, fill by turns and
permitting because of this to soften the water allocation. Operators
manage volumes as they wish it. The management passed of the service
availability (debit pressure, time) to a volume service. Volumes in the
exploitation entry are then known with a better precision. Volumes
restraint had for consequence a considerable water economy.
in the same way, known volumes adjust the usual conflicts between
operators and the “aiguadier: water manager”. The responsibility of a
faltering service is specified and is localized. Since, it is possible for an
agriculturist being part of a GIC to separate what he pays like available
volume in the basin and his contribution in the invoice, to the different
losses that are operated between the water source and his individual
basin. It is an analytic accounting of the water servicing, since its
production until its use. These basins are constructed by the irrigators’
LEBDI Fethi – INAT 28
Water actors, organization and management:
The water sector in oases regroups a certain number of public and private actors,
- The resource production,
- Its mobilization
- Its exploitation and its valorisation.
a - The public actors in the management of the agricultural water
The state and the administration remain the main actors in the mobilization, the
transfer and the transportation until the user. In irrigation the Ministry of
agriculture and Hydraulic Resources is organized in specialized General
Directions, either in the forage (Governed polls), either in the mobilization
(CRDA), that in the resource management and the follow-up of irrigated
perimeters (DG/RE, DG/GR, CRDA).
At a regional level, the CRDA assures the implementation, the follow-up and the
coordination of the agricultural politics fixed by the state. It arranges
popularization structures and technical precincts of exploitation and maintenance
taking care of equipments and water resources. In the same way, within the
CRDA, a cell assures the follow-up and the private actor aid (GIC).
Concerning the treated used waters and employees in the irrigation, purification
stations, under tutelage of the Ministry of the environment and the regional
development, assure the production to the profit of irrigated perimeters. In oases,
the treated used waters can act as balance to the windbreak around oases and
to fodder, arboriculture or truck farmer parcels outside date palms parcels.
b - The private actors
The private actors come to supply the administrative device in the management
of the agricultural water, and if they are not individuals, are regrouped then in
GIC (Collective Interest Grouping) or in agricultural society’s enhancement, that
exploits directly the water resource and the hydraulic networks.
In the same way, the agricultural professional organizations play an important
role to catalyse the agricultural development (rooms of agriculture, Tunisian
Union of Agriculture and the Fishing (UTAP), survey and works enterprises
having to work in the water sector (equipments maintenance, new works,
subcontract of maintenance works, etc.…).
LEBDI Fethi – INAT 29
c - Relations between the GIC and the Administration in the irrigated sector
In the individual exploitations on surface wells, the allowance function is
assured by the CRDA, insofar as watertables are submitted to a follow-up
of their charges and their exploitation. It is the case of certain oases in
Kebili or in Gabes.
In the public perimeters, the CRDA (regional administration) assures the
set of functions, with the exception of the valorisation of water, which is
the spring of regrouped agriculturists in GIC or not.
The GIC structure, composed of operators, and its working exclusively
dedicated to the oasis, permits a management more adapted to this one.
The applied management is an overtime of water elder rights for the
traditional oases or an objective water allocation for the new creations,
that concern a restrict territory, personalized by the oasis.
GIC interests are those of adherents exploiting the oasis. Also, their
objectives are they near of preoccupations and agriculturists waiting, who
control it besides and orient it according to their immediate or future
The size and the proximity of this structure allow a management more
adapted to local specificities and more understanding opposite to
The strong psychological impact of the re-appropriation water at
operators, their involvement and their responsibilisation is otherwise able
to sensitize them on the modernization stakes of irrigation, of the economy
of water and its valorisation, as well as the necessity to perpetuate the
resource and the collective facilities. It is the stake of a succeeded transfer
of the administration responsibilities in the GIC.
The GIC maintains some direct relations with precincts of irrigated
perimeters and the Farming Genius, of the CRDA (Regional administration
of Agriculture and water resources). It develops some continuous relations
with the GIC cell of the CRDA. This last has for mission to frame the GICs
(or WUA) since their creation, while assuring the sensitization of
adherents, the formation and the technical and administrative framing of
the advice members of the GIC and the pumping station manager
“Pompiste” and “aiguadiers”. The GIC cell assures thus:
Help to the GIC treasurer, for the financial document holding, the
establishment of the financial reports and the estimable budget.
Help to the president for the GIC management
LEBDI Fethi – INAT 30
The pumping station manager formation, for the starting up and the
pumping station maintenance,
The pumping station manager and the “aiguadier” formation in
Otherwise, relations with the chief place authorities (Delegation, Regional
Governorate) bring often a help to the possible conflict regulation.
Relations between on the one hand the GIC and the CRDA and on the
other hand recipients within are fundamental. The GICS, besides their
implication in the water management, facilities and hydraulic networks,
play a role of a development sector at the local level, while assuring:
Functions of service cooperatives (to merchandise inputs,
availability of production factors: mechanical negotiation, etc...).
Possibilities of agricultural product merchandising by the GICS
(realization of refrigerated units, etc...) are foreseen by the law 43
Because of this, relations between the different partners are specified by
The relation between agricultures and the GIC is institutionalized in a
contract called subscription contract, specifying rights and duties of each
The relation between the CRDA and the GIC is institutionalized in a
contract called management contract, specifying different contracting part
ii. Water tariff
Three types of tariffs are in progress, according to the irrigated perimeter, its
creation and its development and the period in the year.
The monomial rating: it is proportional to the consumed water volume.
The objective is, with the progressive increase of the m3 water tariff, to
arrive to a partial recovery then total of expenses of the network working
and maintenance, by sales of water, and to assure a better consecration
of the water value, permitting a bigger restraint of the demand. This rating
to the volume is spread but is not yet completely generalized in oases,
because of the absence of numbering. The middle numbering rate is very
strong and is in the order of 96% of water product volumes. The weakest
numbering rate is recorded in Gafsa (Ref: DG/GR). On the other hand, a
rating to the hectare or the hour is in force.
LEBDI Fethi – INAT 31
The binomial rating: it foresees that agriculturists pay for a stationary
part for a volume of exemption and a tariff to the supplementary m3. This
rating not only aims to make support costs fairly by users, but also to
inflect their behaviour in the sense of the water economy and a better
crops intensification in winter. This rating is not yet generalized and results
of its application in oases must confirm the adequacy or no of the rating
binomial with objectives of water economy.
Consulted agriculturists Opinions (Kebili) are shared: those that have a main
work another one that the Dates cropping but that are owners in an oasis, pay for
the stationary loads that indicate their right on the one hand to water and on the
other hand their conscience of the water economy. But present farmer majority
every day prefer the contribution by hectare on their workplace, showing this fact
that the payment of a stationary load indicating that they arrange this privilege
water doesn't go in their conception of their right to water.
Tariffs to the m3 are variable from a GIC to the other or from an oasis to another.
They depend on the water source (artesian or pumped) and of affected loads to
the repair or the maintenance as well as the employees. The water cost is
0.010Dt / m3 in Kebili, 0.024 Dt in Tozeur and 0.032 Dt in Gafsa. The majority of
the GICS applies a water cost around 0.010Dt. It remains on this side of tariffs
usually met in the other irrigated perimeters.
A forfeit is also instituted to the hectare and can go from 200 Dt to 700 Dt,
according to the budgetary balance of the GIC and the guarantee of committed
expense recovery. On the basis of consumption around 20000 m3 by hectare one
recovers costs of 0.010 and 0.032 Dt / m3. It is a majority of GIC (meadows of
84%) that applies this payment concept of the water service and that arrives to
cover more than 80% of its expenses, with the risk of expenses non planned for
the thick repairs (although it is supported by the CRDA).
Other oases function by hour (meadows of 16%) and one especially recovers this
concept in oases to strong rate of fundamental partition and small sizes
exploitations. The contradiction to these concepts of water sale is at the same
time, the strong equipment in counters, without one really recovers a sale to the
m3. Management contracts are concluded between the GICS and the CRDA and
subscription contracts to water are concluded between operators and the GIC.
Tariffs are multiple among oases:
- In the region of the Jerid (Tozeur), a stationary tariff to the hectare can vary
from 150 to 700 Dt/ha or a tariff at the hour, from 2.0 to 5.0 Dt/h.
- In the region of Kebili the hourly tariff is 1.0 to 3.0 Dt/h.
- In Gafsa this same tariff varies according to a service of day or night. During the
day, the tariff is 3.25 to 3.5Dt/h and during the night, the tariff is belittled to 2.5
LEBDI Fethi – INAT 32
- In the region of Gabes the tariff by hectare is around 210Dt/ha and the hourly
tariff is 1.2 to 1 .5Dt/h.
A yearly increase is applied by the GIC, in order to accelerate the recovery of
costs out amortization, to encourage a more prudent water management and a
faster adaptation of water economy techniques.
Loads of water comes back to meadows of 60% for energy and pumping
expenses and the remainder is shared between the maintenance, a lot more
curative and employees.
The water price proposed by the administration to the GIC has the tendency to
anticipate the price to which water should be sold for expenses recoveries,
especially when there is a total transfer of prerogatives of network management
toward the GICs, that it will be autonomous concerning financing. This initiative of
the administration is a discriminating act in its strategy, in the sense where it
uses its authority to fix this selling price to agriculturists. It dispenses therefore to
the GIC a brutal spread when it will be autonomous and that would be, very badly
discerned, not to doubt even though it is justified.
Direct impacts of the water rating
o Improvement of the rate recovery of the working and the maintenance
o Reduction of the subsidy balance.
o Certain exploitation balances are positive; the excess of recipe represents
an involvement to facilities renewal.
o springiness of the water demand is relatively weak
† Absence of analytic accounting.
† Present tariffs don't contain stores for the facilities renewal.
† Weak agricultural intensification rate especially in winter.
† More fundamental problems.
† climatic variability often minor influence less, in irrigation peak time, in the case
of oases, than energy costs, on the weak or the big water consumption, therefore
influence on loads owed to the irrigation.
† The loss of the underground water charge generated an energy over-coast, not
foreseen in the origin.
- Future orientations
† Improvement of the volumetric (monomial) rating
† Assessment and possibly extension of the binomial rating
† Survey under the water tariff impact in view of its actualization and its
integration in a tariff plan
LEBDI Fethi – INAT 33
3 - Associated constraints to the water management of oases
3.1 - General observations
† results recorded by the irrigation sector are satisfactory to certain
considerations, but remain again on this side of potentialities and performances
verified on the land and authorized by the production modern techniques, in
particular, had consideration in particular to the weak intensification, generated
by water availability and a better water service of, water allocations of in
† a proportion that is not important of the irrigable surface, is maintained again in
the first layer from up (palm) production system, in spite of the heavy investments
agreed for provision in oases water.
† The measure of irrigation and the economy impact of water require a finer
analysis reflecting technical and economic performance diversity in the different
† The bad water application generates a long-term hydromorphy and sol salinity
risks, in spite of the purification effort and committed drainage at the time of the
The consumption of water stays strong in peak time, in oases, in relation
to allowances, what cannot reinforce the water resources management, for
what is a water allocation in particular.
† in fact, the irrigation changed production systems that prevailed before the
equipment indeed; but the adaptation and the flexibility of answer to the market
are not yet acquired, because in oases, arboriculture layers, of vegetables, of
industrial crops or the associated raising remain in an family or market restricts
† The irrigation through the geothermic didn't reach its limit again and extensions
are possible, active from 120ha to 300ha in the south.
† The resource limit (watertable in particular) or its quality limits offered
potentialities by irrigation, in a lot of sites in Tunisia,
LEBDI Fethi – INAT 34
† The pumping cost in the individual wells weighs on exploitation loads of the
agriculturist who burdens its clear profits (150 to 200millimes by pumped m3), but
weighs also on the energizing invoice of the country, especially that the oil barrel
passed the rod of the 50 $ for a long time,
† certain questions can today, after some years of the installation of the water
economy program, to be asked, without forgetting that the objective of water
mobilization and economy is stronger than means put in work:
What is the impact of water economy techniques adopted in oases, in
technical terms (saved quantities) and in economic terms (m3 cost).
On the other side that the present costs of the m3 water, which are
relatively low in oases, in comparison with dam’s waters in the other irrigated
perimeters, two questions are asked:
To what real cost of m3 water, techniques of water economy begin to
become profitable for an agriculturist (what is invested in water economy is lower
than the pulled profit of the water purchase)
To what level the lost water economy would be technically possible
(how much can improve one to the maximum the working of an irrigated system)
and would be it less or more expensive than the production of a renewable
supplementary resource (an over flood waters transfer for example).
What can be incitements granted to agriculturists to accept a water
invoicing according to the numbering.
† The durability of the oasien system is also confronted to the:
o associated risks to the important future withdrawals,
o “artsianism” disappearance, and risk of water salinity,
o excessive pumping heights,
o a drying up of the Tunisian outlet, in the region of “chotts” and setting up
Of the artesian basin (HERE),
Of the Tunisian outlet (HERE),
Of Ghadames basin (HERE),
Of the basin of the Algerian - Tunisian Chotts (CT),
Of Khoms-Zliten coastline (CT).
The more precise information development, with a particular attention
in zones with identified risks in oases (takes in account of environmental
Then setting up of a follow-up of the environmental corposant, with
LEBDI Fethi – INAT 35
soil quality indicatory
water ascent indicatory
of the watertable quality and the drainage waters indicatory
following-up of “chotts” and watertable interaction
3.2 - The resource or the available debit decrease
These aquifers systems are with important resources but with a very weak
renewal otherwise without renewal. During years 1970, withdrawals were lower
to the regulating resources and waters coming from the artesianism permitted to
play the leaching role of the salty soil. Currently, in certain oases, the recourse to
the pumping and sometimes to the watertable, to assure a balance during the
peak time, constitutes a supplementary financial load and an environmental risk.
- In watertables, the increase of wells number, sometimes illicit and their
equipment intensified the watertable exploitation. It resulted in a bigger exchange
between watertable and irrigation waters, generating a certain hydromorphy.
Some capillary ascents are generated by seasonal piezometric fluctuations that
can go until 2 to 3m.
- “Chotts” proximity, lately a micro-climate source auspicious to the existence of
oases, will drag in case of overexploitation, a reversing of the underground out-
flow sense that risks to invade oases by very salty waters.
- Piezometry reduction and artesianism loss make imperative the recourse to the
pumping. To the contrary of pumped forages, the artesian forages cannot be
closed in absence of the irrigation. These forages debits are inexorably lost in
drains when water demand is weak. This resource unavailability can count itself
in millions of m3/an (about 6 Millions in 1995, for forages of Fayçal, Kettanas,
Zarats, Teboulbous and Zerkines in Gabes).
- Supplementary loads that are a result from pumping appear in water forages
exploitation, directly under the financial responsibility of the GIC.
- The resource failing results partially from water losses in the distribution
networks and in the parcel. But it also results in unsuitability between the raw
needs of the oasis and the available resource. The continuous fictional debits at
the disposal of oases are very disparate according to oases. They can overtake
in the rare cases 1l/s/ha but can go until 0.6l/s/ha in other cases.
Nevertheless, the interrelationship between the continuous fictional debit and the
water contribution to crops is not direct, because of rates variability of soil
occupation and speculations that comes with date palm. It is to notice that to
equal continuous fictional debit, more the contribution to crops is important, more
LEBDI Fethi – INAT 36
the rate of soil occupation is weak (the efficiency of the tertiary network is enough
- Management rules of tour water can impose an important water allocation to the
agriculturist. This last cannot manage it only with an adequate infrastructure of
automatic distribution inside his parcel. The available debit cannot be adapted to
the transportation and distribution infrastructure.
3.3 - Adequacy between water demand and crops objective needs:
The irrigation as exercised in oases is not always conducted according to the real
crops needs and the water contribution is governed by several factors, variable
from an oasis to another (irrigation technique, water availability,…) and no by the
only evaporative demand and water stocks in soil.,
This management mode can mislead water stress and therefore yields falls or on
the contrary an important water contribution and a resource wasting, by losses by
Objectively, the climate intervenes by the potential evapotranspiration (ETP) and
the rainfall. The potential evapotranspiration has been estimated by several
authors, of which mainly Pennman, Blaney-cridlle or the formula of Riou,
established and validated in certain zones of Gabes region. The necessary data
to set it up (maximal and minimal temperature, latitude) are more accessible than
those requisite for the use of Pennman formula. All these formulas permitting to
estimate the ETP have not been regionalized and have been posed this problem
of their use in zones where they have not been established nor validated, in
particular in oases.
In the same way, the global rain doesn't intervene directly in needs calculation
since alone the infiltrated rain and restraint in the roots zone permits crops food.
It evidently poses the problem of the efficient rain evaluation, for different
vegetative phases, along the crop cycle and according to these last and their
physiological behaviour. One can disregard rainy contributions at the time of
irrigation periods, in oases and one assigns solely to rain the role of salt leaching
that is very important, in a context of irrigation with the brackish water.
Different tools exist to estimate needs in water (Cropwat model, put to the point
by the FAO), or the efficient rain, by the relation between the rain efficient and
the middle rain of a period data, advisable by the US Office of Complaint.
Cropwat model integrates this relation in the efficient rain calculation and give
cultural coefficients according to the vegetative stages of different crops.
In oases, this type of models remained to validate and to regionalize, on different
crops and to the short time steps (some days to a decade), in order to make an
irrigation piloting tool of it and no solely of hydraulic systems conception.
LEBDI Fethi – INAT 37
This question is even more complex in this oasien system characterized by a
specific microclimate and by the presence of three cultural layers (palm,
arboriculture, fodders, market or industrial crops). This specificity results in an
effect of shadiness that reduced the evapotranspiration at the level of the two
layers situated under the palm.
Otherwise, water competition (and even mineral) enters the three layers,
complicates a lot the needs evaluation, so well that currently no applicable
approach is available. It is of as much more important to deepen than
strategically, one counts among others on the adequacy of water demand and
the objective needs of crops, for a water economy but also for a durability of the
balance, on the one hand between the demand and the resource and on the
other hand a salt stability of soils and the watertable.
These needs in water go in pair with the irrigation management system. Indeed,
a crop as for example lettuce, that is spilled in certain oases (Gabes), is very
appreciable to water deficit since the optimal suction required in soil must be
constantly close to the capacity in field the (0.33atm) and a long water allocation
can have some ominous effects.
On the other hand, a fodder crop (the Alfalfa) in the same oasis doesn't require
humidity in soil close to the capacity in field and can tolerate a water deficit which
can correspond to 1.5atm, therefore a water allocation that must be adjusted
according to the water stock in soil.
One doesn't note, except for research tests, no generalization of a piloting
system in oases, either through lysimeter slots, or the installation of
tensiometers, or the thermal measures on leaves surfaces. In the same way, it
has been developed not again of an irrigation warning system in an oasis, thanks
to the given agro- meteorological short-term forecasting.
DG/GR (Administration of rural engineering, Ministry of Agriculture and water
resources: Report synthesis of the GIC/PPIS: 2005) figures show that in the year
2004/2005 the produced water volume by 117 GICs in oases, is 294.5 Millions of
m3, of which 283 Millions of m3 posted through the installed counters and 11.5
Millions valued. This produced water volume served to the irrigation of a surface
in oases of 115072 hectares. It gives a mean consumption to the hectare of
It is to note that consumptions in water are most elevated in Kebili oases and
then Tozeur oases (17500m3/ha). Gafsa and Gabes oases are not to
predominance date palm and especially lean on the market and industrial crops,
with a mean consumption by the hectare of meadows of 4700m3/ha.
LEBDI Fethi – INAT 38
These values stay strong in spite of rehabilitation, modernization or water
economy efforts in oases.
3.4 - Saltiness constraint
The quality of the irrigation water, associated to soil, limit often production fields.
In Tunisia and in particular for the underground waters watertables contain only
8% of resources possessing an acceptable saltiness, lower than 1.5 g/l and only
20% of the resource coming from the deep watertables answer to this condition.
Irrigation waters in Tunisian oases are often characterized, to some exceptions
meadows, by a strong dry residual (more than 4g/l). The very strong evaporation
and the weak depth of the water plan encourage the increase of the salt
concentration dissolved in water. Their leaching by irrigation waters and the weak
food from rains make that these waters are concentrated more than those of the
deep watertables, already loaded. These watertables are prompt and are bound
to the oases presence and irrigation waters.
Because the rock reservoir is with weak permeability and a reduced thickness,
water resources in these aquifers are relatively modest in relation to the deep
watertables. Consequences of their exploitation are translated by raised saltiness
water, which is the origin of weak crops yields. This excessive saltiness to the
origin of the soil salinity, especially when the drainage network of is non-existent
- Some questions remain asked:
Soil salinity processes in the irrigated perimeters (capillarity in badly drained
oases, salts direct contribution by irrigation,…);
The rehabilitation of salted soils by drainage and irrigation integrating leaching
Conditions of salted water use, of more than 4 g/l, according to the type of soil.
Plantations tolerance and the selection of species and very tolerant varieties to
salt and presenting an economic interest; salinity risks of aquifers at long-term;
fertilization in saline environment;
The economic opportunity of brackish water desalination (>10 g/l) is the use of
the renewable energies (solar especially).
3.5 - Hydromorphy and Drainage
A big exchange exists between the watertable and the irrigation waters,
generating a certain hydromorphy. Some capillary ascents are generated by
seasonal piezometric fluctuations, that can go until 2 to 3m and that make that,
when the irrigation water allocation reaches some strong values (30 same days),
LEBDI Fethi – INAT 39
crops as henna in bottom of palms persist thanks to capillarity and resist to salts,
with very weak yields. Irrigation waters are characterized by a strong dry residual
(more of 4g/l). The very strong evaporation and a weak depth of the water plan
encourage the increase of the salt concentration dissolved in water. Their
leaching by the irrigation waters and a weak alimentation from rains make that
these waters are very concentrated in salts.
When the oasis downstream is adjacent to a depression without outlet, the
hydromorphie appears and the drainage imposes itself. When forages are
artesian, the continuous out-flow outside of needs periods (winter) contribute to
nourish the watertable on the filterable soils, of which the sand rate is superior to
80%. The present gypseous crust in relative depth, little permeable, provoke this
phenomenon of hydromorphy. The classic drainage network in oases is an open
collectors network, that when it is badly kept, don't manage to pull up the
watertable ascent. Actions of curing drains are part of the maintenance actions
written down in the GICs mission.
Oasis hydromorphy situations can present themselves as follows, with one
appropriation mode of collective water, functioning according to the water
- Oases are characterized by non hydromorph soils. The crop system is
predominated, on the lower layers, by arboriculture, fodder crops, fodders and
the industrial crops,
- Oases are characterized honestly by hydromorph soils. The crop system is on
the lower layer, in market and fodders predominance,
- Oases are characterized by depth hydromorph soils. The crop system, besides
date palms, is characterized by arboriculture market, fodders and possibly
industrial crops (Gabes).
3.6 - Drainage waters reuse
Evacuated drainage waters during the wintry season are more important than
those evacuated in summer. Saltiness values in summer are stronger than in
winter but can be very neighbours, because waters evacuated in winter entail all
the salt accumulated at the time of the irrigation period. Drainage waters
averages depend on oases (soil saltiness and irrigation waters saltiness) and can
go from 5g/l to more of 12g/l. Nevertheless, the proximity of a surface watertable
and the filterable soils make that the saline balance of the watertable becomes
more pronounced, in spite of the existence of the drainage. It is due to the weak
rainy quantities in the oases regions, which permit the best leaching. This last is
especially assured by irrigation waters.
The question stays as for the waters recuperation possibility of good quality
drainage, distant of “chotts”, on non hydromorph soils available with big drainage
LEBDI Fethi – INAT 40
porosity and profitable crops of salty waters. This process must not affect the
3.7 - Partition and agrarian reform problem
In Tunisian oases exploitations are marked by a relatively reduced size of by the
partition, as inheritance results. Small size exploitations become little profitable
and are quit progressively by their owners. In Chenini oasis (Rhouma, 2004) in
Gabes 50% of the agricultural exploitations have less 0.1ha and became real
gardens, against only 12% that overtake 0.25ha. Indeed, the oasis counts 165ha
for 1249 owners. In Degache in the Jerid (Tozeur), 86% of the agricultural
exploitations have a surface lower than 0.5ha and only 10% have a surface
understood between 0.5 and 1ha. The 125ha’s surface of Aïn Errebh and Zaouiet
El Arab oases is distributed on 470 owners.
Nevertheless, the new access mode to the earth and the fundamental credit
measures, permitted the new oasis setting up (Rjim Maatoug, Ibn Chabat,etc.),
young agriculturist installation, agricultural technicians or promoters, on surfaces
of about 1ha. The amount of the fundamental credit varies from 30000 to
100.000Dt (1$=1.3Dt), repayable on a 25 years period, with 5 years of grace.
In the traditional oases the partition is much accentuated and the agrarian reform
agency began a program oriented toward these oases.
The agrarian reform in irrigated public perimeters is governed by the law n° 63-18
of May 27, 1963, which has been modified and is completed by the law n° 30 of
March 6, 2000 allowing the Agricultural Fundamental agency loaded of this
reform application, to spread its mission in particular to the set of the irrigated
public and private perimeters of the country and to assure the follow-up of the
enhancement on these perimeters. The objective of the agrarian reform is "to
assure optimal farming possession exploitation and a rational use of the water
irrigation inside the irrigated public perimeters. For this, a modification of the
fundamental plate inside these perimeters is necessary in order to proceed to
grounds the fundamental and legal cleansing, to the dispersed parcels
regrouping and to the irrigation water distribution and use.
The agrarian reform law rests on four fundamental principles:
i - The property limitation by the fixing of a minimal size and a maximal size
varying with perimeters and their technical, economic and social features: the
fixing of the surface layer especially takes account of the socioeconomic aspects
in particular so that this share layer procures to the operator a minimal added
value. The definition of the surface ceiling obeys essentially to an economic
criteria, the one to assure to every attributive an irrigated surface bringing back
him an income at least equal to the one that it got before the enhancement by the
irrigation, on all the surface that he possessed inside the perimeter.
LEBDI Fethi – INAT 41
ii - Owners contribution to hydraulic planning expenses : this contribution is
proportional to the discounted increment by the introduction of the irrigation, it
depends on several factors of which the pedological category of the soil, of the
crop nature, of the investment amount by hectare… The maximum investments
amount taken in account in the contribution determination is often extensively
lower to the real investments cost. To fulfil the contribution to hydraulic planning
expenses, owners can be paid in nature while yielding to the State a land surface
cloud or to pay cash while pouring to the State “the amount of the surface venal
value that they should have given up for free ".
iii - The fundamental reorganization in order to assure a rational use of the
irrigation water and a better execution of rotation plans and setting up:
fundamental reorganization operations have the tendency " to constitute some
continuous, regular parcels and whose limits adjust to the distribution and the
use of the irrigation water, enjoying independent accesses and also brought
closer that possible of the exploitation seat ".
In order to make that, the state can proceed to the fundamental and legal
cleansing of lands and the parcels regrouping and dispersed parcels. Owners
must do some fundamental amenities to complete these reorganization
operations and to assure an adequate enhancement conditions by the irrigation.
The article 16 of the Law previously mentioned precise cases of hold in account
of these amenities whereas the article 17 stipulates that the expropriated
surfaces could serve to the small exploitation enlarging or the new agriculturist
vi - The setting-up obligation of distributed land : agricultural land owners situated
inside an irrigated public perimeter are held to put them in value by their irrigation
equipment, their protection against waters stagnation, by the constant and
regular practice of irrigated crops and the repair and the hydraulic facilities
safeguard being inside the exploitation ".
Is considered enhancement, all earth of which the 90% at least of its surface are
irrigated within 5 years from the irrigation water supplying.
The non consideration of this obligation drags, besides sanctions foreseen by the
law, the right decay to the irrigation water supplying.
Execution organs of the agrarian reform are composed of:
- The National Commission Irrigated Public Perimeter: which is assigned to give
out its opinion on all recommended measures by the administration for the
setting up of the Agrarian Reform law.
LEBDI Fethi – INAT 42
- The Agricultural Fundamental agency is an administrative structure endowed of
the civil personality and the financial autonomy whose role is notably the
application of the agrarian reform and the follow-up of the enhancement in the
irrigated public perimeters, and the realization of fundamental planning
operations in the private perimeters.
Contrary to the reform of the agrarian structures of the decade 1960 that was
enough rigid, the present reform in the irrigated public perimeters is applied with
suppleness and almost always with the consent of interested parties and the
regional authority contest and especially the local ones.
Noted difficulties in the application of the agrarian reform in irrigated sector:
Agriculturists reticence to lands agrarian reform, notably in zones where
the exploitation size is very reduced;
The numerous litigations between co-owners;
Sometimes, the register realization land took place before the completion
of the agrarian reform, thus necessity of recourse to the total expropriation
to regularize the setting up of agriculturists on shares of agrarian reform;
The local sectors extension to the expenses of certain public perimeters
created by decree and distributed;
The setting up of different arrangement planned for the enhancement
obligation of earths equipped, etc.
After a long period or the priority was given to the hydraulic resource
mobilization, the rational management of the weak hydraulic resources as well as
their optimal valorisation are henceforth the main objective of the new water
politics in Tunisia.
In the new context of structural adjustment and internationalization, water
resource acquires a strategic character in the economic and social development
of the country.
3.8 - Social constraints to the private involvement
in the water management
There are two obstacles types that sometimes impose themselves to concerned
operators involvement in the water management of and flexibility that they can
develop to be conscious of the market mutations and to answer there with
celerity and efficiency:
LEBDI Fethi – INAT 43
Those emanating some public services:
- the groupings constitution must emanate the interest and real will of operators
and concerned parts directly. Again today, the public services, conscious of the
interest and the importance of participative water management, open out efforts
so that associations see the day. What handicaps a priori, the total implication
process of the agricultural operators in irrigated sector, since the initial phase and
give the impression of an administration strong presence.
- From 1999 (law 99-43 of May 10), conscious of this handicap, the GDA(s) are
created solely to the demand of owners and agricultural operators, without
advertisement formalities or previous consultation.
- The approval procedure allows these associations to participate but also to
constitute itself if need be civil part, what implies legal knowledge aspects.
- The financial limits of certain associations make them little viable, otherwise
dependent of public service subsidies, under shape of more interventions in
repairs or the maintenance.
- At the time of the projects technical survey, the concerned operators participate
actively in the setting up of the technical solution and management of the
irrigated system, what facilitates thereafter associations’ creation procedures, but
integrate the set of the technical, economic and social aspects in the planning
Those emanating concerned water users:
- The association intervenes only individually by its users. Indeed, subsidies and
the financial and fiscal actions in general, are a matter for a gait of individuals
and no the group. In the same way, the existence of a sanction regime inflicted to
the infringing, in the same space managed by the association, is governed
individually. There is there a collective responsibility ignorance of water users,
within a same association.
- Difficulties met with operators are relative to their implication as partner,
possibly advanced in it by their modest material conditions or their lack of
schooling. An educational gait is necessary, in order to rehabilate the mind
responsabilisation of concerned parts.
- The relative generalization lack of information and formation actions, of brought
closer popularization and of sensitization. A considerable effort is achieved in
particular by the DG/GR and the AVFA, helped in it by the IRESA and the
DG/PA. Nevertheless, actions of formation are part of a component to it alone, in
all development projects.
LEBDI Fethi – INAT 44
3.9 - Popularization and Research:
In Tunisia, date palm benefited of the attention that it deserves concerning
research/ popularization and this fact of a rational development. Actions of
research in the departure touched the palm in a piecemeal, prompt way and
often limited in the time. The agriculturist is the most often non aware, non
sensitized or non convinced. Research and the popularization have been called
therefore to play an important role to promote the sector and to protect its
The played role by this tree on the socioeconomic level in production regions in
particular and on the country economy was in general the principal stimulant of
research actions, popularization and development enterprises these last years to
give to the palm its suitable place among principals axes of Tunisian agriculture
development. The creation of an Interprofessional Grouping for Dates (GID), a
phoenicicole Center specialized in research and the promotion of research
actions, in partnership between researchers, persons responsible of the
development and agriculturists permitted to concentrate on the direct
preoccupations of the sector. The water economy, the safeguard of
“phoenicicole” heritage and the sanitary security of oases are the main actions
around of which research and the popularization turn.
The liberalization of commercial exchanges of agricultural products requires the
funding of the popularization sector so that it can face the new requirements of
the sector and agriculturists. The advice becomes targeted and fast. The
profession should play in this context an important role, in the pipeline of the
advice at agriculturists where each category of agriculturists will have access to a
particular and targeted popularization.
A large number of operators passed the 60 years age and a lot of between them
didn't pass the primary or secondary teaching stage, whereas reached some
superior studies very little. In the objective to modernize, to rejuvenate and make
agriculture dynamic in oases, in a context of quality export objective, and in the
goal to allow agriculturists to benefit from a modern and adapted technological
packet, professional formation and retraining programs, oriented also toward
agriculturists children to assure the relay, must be strengthened around oases
and through the profession. The experience of young promoter installation
descended from superior graduates must continue and must even push.
The popularization pursued until these last times wanted to expose to the
agriculturist an especially technical advice panoply, but this last doesn't seem
always to be a part taking since the process departure, but merely, a link of a
transfer system and technical demonstration for some among them (information
days, spotlight television, …etc.). Agriculturists are placed in recipient's role
rather than actor's role.
LEBDI Fethi – INAT 45
Questions stay asked as for:
What expression must take a popularization demand, in Dates sector?
How to reinforce proximity structures around oases?
What use of the new information technologies and disposition of agriculturists
and son of agriculturists, having the capacity to resort from afar to information,
following a made from afar request.
This last use can succeed to the setting up of a knowledge network on oases and
date palm, as well as a network of experts and shared experiences. The two
human components (research, formation, popularization, and professional and
producers institutions) and technique are foundations of this network.
LEBDI Fethi – INAT 46
This survey put the accent on challenges to which the irrigation in oases is
confronted; face on the one hand to the natural resources, in water and in soil,
rare and fragile of the point of view quality. On the other hand and broadly
speaking, agriculture is facing opportunities that can present a more and more
demanding, aggressive and globalize market, but especially making intervene
together united country groups, among others from an economic point of view.
It reviewed besides the old irrigation history in oases, the exam of exported water
quantities through products of high added value that are dates and olive oil. This
exam confirms the monetary value of the m3 water and its valorisation degree,
as a result of a technical performance but also of all the achieved work on
markets conquest and their target. If the m3 of water is sold around 0.030Dt, it
brings back directly by dates more than 2 Dinars, according to years and the
fluctuations of the market and the harvest. This m3 of water brings back a lot
more that the 2Dt, if one considers all appendices activities in oases and that pull
their same existence from the these oases development (handicraft, tourism,
The main questions that reflect this survey on the sector of dates are the
To continue the water economy program, in order to improve the hydraulic
service (better water allocation) and to increase again irrigation
efficiencies, there where results are not even satisfactory.
To decrease water losses to all levels of its production (artesian forages
losses in winter), its mobilization on the whole of hydraulic networks and
its application to the parcel, what will permit to improve irrigation schedule.
To come with the agriculturist in methods and means of irrigation piloting.
To promote again to more the numbering and the volumetric rating.
To stop extensions that already touch to fragile resources - demands
Improvement of drainage systems and conditions.
Generalized control of the soil saltiness, following irrigation conditions
(water and soil quality, and leaching conditions).
LEBDI Fethi – INAT 47
Promotion of the reuse of the drainage waters, there where conditions of
soil durability are not compromised (fodders and filterable soils, frequently
washed, with an outlet to the downstream).
To increase the intensification in oases, especially in winter and with a
tariff that is already relatively low.
To integrate more again adapted rising to oases, in particular ovine.
Formation and framing of the different water actors in oases, in particular
for what are some efficient applications to the parcel and the worry of the
The framing by the formation in particular, of GICs (or WUA) and
especially of the staff in direct contact with the water management.
Popularization actions must be reviewed, while taking account of the new
context of participative water management.
Popularization actions must touch all Dates chain (production,
conditioning, marketing, etc.).
To continue to refine, by research, water needs on stacked crops in
A survey would be appropriate, that initiates procedures of control and
observation of the oasis evolution, particularly of the point of natural
resource view (water, soil), that values the present system and effects
(advantages and inconveniences) of the achieved amenities, facilities and
techniques introduced and that refines constraints that pull up the
efficiency very well is the durability of system oasien, to the future.
Indicators development of irrigated oasien system evolution.
This survey can be to the origin of a convenient plan that guarantees
efficiency and durability objectives of oasien systems in Tunisia.
LEBDI Fethi – INAT 48
1- Statistiques sur les oasis (nov. 2006): Ministère de l’agriculture et des
2- Les cahiers de Tunisie (1957) : Institut des hautes études de Tunis.
3- Amélioration de l’irrigation dans les oasis du sud de la Tunisie (nov.2005).
Ministère de l’Agriculture et des ressources hydrauliques. DG/GR.
4- L’amélioration de l’efficacité de l’irrigation pour une économie d’eau : cas
d’un périmètre irrigué en Tunisie (oct.2000). Ciheam- Plan Bleu.
5- Potentialités androgénétiques du palmier dattier (2002) : Chaibi.N and al.
6- Concurrence et complémentarité des espèces végétales dans les oasis
(1990) : Michel.F. Ciheam- Options Méditerranéennes.
7- Etude du positionnement de la branche dattes (sept 2000) : Agence de
Promotion de l’Industrie. Tunisie.
8- Traçabilité de la filière dattes (sept 2006) : Groupement Interprofessionnel
des Fruits. Tunisie.
9- La nappe du continental intercalaire du Sud-est tunisien. Analyse de la
situation actuelle (Dec 2001). Rapport : Abidi.B.
10- Bioclimatologie des oasis (1990) : Riou.C. Options Méditerranéennes.
11- Dynamique des législations du foncier et de l’eau pour un accès équitable
et une gestion durable des ressources en eau (2006) : Rapport.
Noureddine.N et Mares.H.
12- La salinisation des sols, incidence de l’exploitation des nappes du sud
tunisien dans les oasis sur la qualité chimique de leurs eaux (Dec 1993) :
LEBDI Fethi – INAT 49