Operational Drainage Water Reuse Guidelines, by Shaden Abdel-Gawad, Professor and Former President National Water Research Center, Cairo, Egypt , Land and Water Days in Near East & North Africa, 15-18 December 2013, Amman, Jordan
1. Operational Drainage Water Reuse Guidelines
by
Shaden Abdel-Gawad
Professor and Former President
National Water Research Center, Cairo, Egypt
Introduction
Given its current population growth rate and need for national food security, Egypt is
forced to develop new lands for agricultural production. Coupled with the expansion
of the agricultural land base is the need to provide an adequate irrigation water
supply. This poses a serious challenge where Egypt has limited fresh water
resources, depending mainly on the River Nile. Therefore Egypt has embarked on a
water conservation program, which includes an Irrigation Improvement Project, and
drainage water reuse.About 12 billion cubic meters of surplus irrigation water are
collected in open main drains each year, but only about 6 billion cubic meters are
currently being reused. Drainage water therefore, represents a valuable resource
which can be utilized in agriculture to meet crop water demands. In the early 1970s,
Egypt adopted a long-term plan to reuse drainage water for irrigation on a more
sustainable basis. Obviously the reuse of drainage water for agriculture plays an
important role in the Egyptian water resources strategy.
The reuse of drainage water may lead to serious salinization problem of soils unless
careful water and salt management are considered. Drainage water may also contain
highly toxic substances from agricultural pesticides or industrial and/or domestic
wastewater discharged into the open agricultural drains, which may cause serious
health problems. Chemical contaminants in the drainage water may bio-accumulate
in the food chain and in the soil profile. In general, the reuse of drainage water in
irrigation has the potential of causing serious problems of soil degradation, reduction
in crop productivity and quality,and animal and human health hazards.
Also, the reuse of low quality drainage water for agriculture poses many human
health and environmental challenges. Villagers, land owners and field workers are at
risk by contamination of the drainage water, especially by pathogens, if they are in
direct contact with the water. Pathogens may also accumulate on the irrigated crops,
which will be a further human health hazard if these products are consumed directly
without being properly washed or cooked.
The success of drainage water reuse in irrigation depends on minimizing the longterm impacts on soils, crops, environment and socio-economic conditions. This
requires applying a package of good practices in managing drainage water and
improving its quality. Therefore, guidelines are needed to assist the water users in
using the drainage water in an environmentally safe manner.
Guidelines objectives
The purpose of developing operational guidelines is to assist landholders to adopt
safe and effective practices for reusing drainage water for land reclamation and
agricultural production of new lands. Also, it could help in determining how to reuse
drainage water in an environmentally safe manner without exerting negative impacts
on human health and the environment (soil, water and crops). The detailed objectives
are;
Avoiding long-term degradation of crops and soil.
2. Protecting environmental quality and human health.
Ensuring the social and economic wellbeing of the farmers.
The guidelines are targeted to landholders, extension personnel, GOE ministries and
agencies, and NGO’s
Components of the Guidelines
To guarantee the success of the development of the Operational Guidelines, three
main components were considered. Those are; the environmental component, where
the reuse of low quality water for agriculture poses many human health and
environmental challenges. Different parameters such as fecal Coliform and heavy
metals should be identified in the drainage water and should be within the acceptable
limits for safe irrigation. The primary emphasis was placed on the protection of public
health and the secondary emphasis was on the impact of external elements in the
water system on the crop production.
The second component was the agricultural component; where using the drainage
water in irrigation can potentially lead to problems of soil salinity, sodicity and soil
contamination that can adversely affect the ability of soils to grow crops economically
or of acceptable quality. So, the agricultural component of the guidelinescould be
used to enable the user to rate the salinity hazard factors and to suggest irrigation
and crop management practices to overcome such hazards. These guidelines are
intended for use on currently cultivated lands as well as on new lands being brought
into production by reclamation.
The last component is the socio-economic component where the reuse of low quality
water may affect negatively the social and economic conditions of the farmer's
population. It is therefore important to define the socio-economic categories of the
farmers, identify developmental constraints, and provide a list of institutions which
can implement an appropriate policy and program interventions. The socio-economic
component of the guidelines could be used to predict the degree of vulnerability of
farmers who use drainage water for irrigation. In addition, these guidelines identify
institutional measures which could be taken in order to mitigate the risks.
Process to Develop the Guidelines
The guidelines were built on an integrated platform comprised of agricultural,
environmental and socio-economic components. The Guidelines development also
benefited from inputs provided by stakeholders and farmers in the study area. The
powerful of the Drainage Reuse Guidelines lies in the fact that it has been developed
from 8 years of extensive field monitoring, data synthesis and integration, field
testing, and stakeholder consultation and inputs.
Steps of guidelines development are as follows:
1. Pilot area selection
Three pilot areas were selected in south El-Hussania as part of the El-Salam Canal
Command area based on different criteria such as:easily accessible, continuous
presence of the landholder in the area, full cooperation of the landholders with the
project and finally representative to different socio-economic beneficiaries categories.
3. 2. Agricultural, Environmental and Socio-economic monitoring program
A major input to the Guidelines development was the data collected from the biophysical, environmental and the socio-economic monitoring program undertaken in
the three pilot areas from 1998 to 2006. The aim of the bio-physical monitoring
program was to assess changes in water quality, soil quality, crop productivity and
levels of pollutants due to drainage water reuse. Monitoring was also conducted to
determine the status of land tenure and changes in land development. The socioeconomic monitoring program aims to compile and assess changes in socioeconomic conditions to support development and modification of policies and
interventions to assist landholders to successfully and safely adopt drainage water
reuse practices for land reclamation and irrigation.
3. Data analysis
Different analysis for different collected parameters were carried out to study the
impact of using low quality water on agricultural and environmental items (soil, water
and crop quality). Also, different analysis were carried out for socio-economic
parameters using SPSS, to assess changes in socio-economic conditions such as
farm level economics (cost and net return for different crops), quality of life and
satisfaction level.
4. National and International Standards
The Operational Drainage Water Reuse Guidelines incorporate information from
various national and international water quality standards such as FAO, WHO,
Egyptian and Canadian water quality standards. Also, guidelines incorporate
information from specialist reports and studies undertaken by local and Canadian
Consultants, to develop water quality guidelines and human health practices for
drainage water reuse
5. Logical Integrated Framework of the Operational Guidelines
The agronomic, socio-economic and environmental considerations are tightly
integrated in the Guidelines structure, where there are primarily 5 logical steps to be
followed in Guidelines application.
6. Testing the Operational Guidelines
Testing the developed guidelines was carried out on two different scales; small sale
testing in demonstration farms and wider scale in pilot areas.
Small sale testing
To test the guidelines under restricted conditions, two demonstration farms
were identified within south El Husseinia plain. The farm size is 5 and 12
feddans respectively. The sites were selected to be representative of the total
area for soil, crops, and irrigation and drainage conditions. The operational
Guidelines were successfully applied consecutively for both summer and
winter seasons. The application of the guidelines showed that the high crop
yield and the soil salinity reduction indicated that the developed guidelines are
reliable and practical on the small scale farms.
Wide scale testing
4. Three new pilot areas were selected to test the developed guidelines in wide
scale areas. One plot in each pilot area with a total area of 50 feddans was
selected to test the operational guidelines in 2004 and 2005. The application
of the guidelines showed that the rice crop yield reached 3.760 and 4.468
ton/fad for summer 2004 and 2005 respectively which is within the national
average of rice yield in old lands (4-5 ton/feddans).
7. Computerization of the Operational Guidelines
A computerized version of the guidelines was developed to fulfill the needs of
decision makers, researchers, engineers and extension specialists. It is available in
both English and Arabic.