NEEDED INNOVATIVE URBAN WATER MANGEMENT
FOR DEVELOPING COUNTRIES, CASE OF EGYPT
Abdelwahab M. Amer
Irrigation and Hydraulics Department,, Faculty of Engineering,
Cairo University, Giza, Egypt. E-mail: amamer8@yahoo.com
ABSTRACT
Water has been a critical component for development in Egypt. As population increases
demand on the limited water supply increases. To meet the competing demands, more
attention is given to non-conventional water resources. As a result, and following a general
increase in wastewater treatment, wastewater reclamation and reuse is expected to increase
sharply over the next few decades and becomes an important aspect of integrated water
resources management. Important projects are being developed and wastewater reclamation
and reuse facilities have been built. This paper presents the status of wastewater reclamation
and reuse in Egypt and highlights the existing reuse standards. Treated effluents in general do
not meet the standards for disposal to watercourses. Positive and negative effects of the use of
reclaimed water for agricultural production are discussed. It is needed to establish guidelines
on wastewater reclamation and reuse. Innovative demand management and supply
enhancement measures have to be adapted, among which low level of treatment and dual
distribution systems.
KEYWORDS
Reclaimed wastewater; reuse criteria; water management.
WATER RESOURCES IN EGYPT
Egypt is a very arid country. The Nile river is almost the exclusive source of surface water. It
provides Egypt with 55.5 billion m3/year. The total dissolved solids (TDS) for the Nile ranges
from 175 mg/l at Aswan to 210 mg/l at the Delta barrages. Deterioration in water quality
occurs in northward direction due to urban water effluent and agricultural drainage as well as
decreasing flow. Canals have water quality similar to that at the points of diversion from the
Nile. Drains between Aswan and Cairo receive run-off from agricultural lands with
satisfactory water quality. Drains in the Delta have extremely variable quality. Drains in the
Delta have extremely variable quality. Some of it receive municipal and industrial wastewater
in addition to agricultural return flow.
Groundwater in Egypt can be divided into two categories. The first comprises the Nile valley
and delta aquifer system with renewable water of Nile origin. The second is the nonrenewable
deep groundwater in the western desert. Shallow small aquifers in the coastal areas along the
Mediterranean sea receive water from the limited rainfall. Nontraditional water resources are
agricultural drainage water, reclaimed water, and limited amounts from desalination.
POPULATION GROWTH AND PER CAPITA WATER AVAILABILITY
Egypt is approaching the stationary growth stage characterized by slow decrease of annual
crude birth rate which reached about 2.7% in 1996 against rapid decline of crude death rate
which has dropped sharply to the minimum of 0.62% in the same year. The settlement pattern
of population whether in rural or urban areas is another important aspect of population
growth. The percentage of rural population ranged between 55.5% and 56.5% during the last
three decades. Water needs for human uses in urban are about 1.5 times that of rural areas.
Considering total renewable water resources, per capita quota was 1893 m3 in year 1960, 967
m3 in year 2000 and estimated to be 673 m3 in year 2025 (Fig. 1).
Population
Fig. 1: Changes in per capita quota of water and population in Egypt, 1897-2025
(Adopted from Khalifa and Abdelmonem, 1997)
URBANIZATION EXPANSIONS
In the last three decades the map of Egypt has been changing considerably. The overpopulated
cities are no more capable to cope with the increasing population. Many new cities, towns and
settling communities in different parts of the country are under construction and expanding
rapidly. Numerous resorts have been constructed along the Mediterranean sea coast, Red sea
coast, and Sinai. Moreover, random urbanization steadily expands at the fringes of big cities.
The newly urbanized areas impose additional stress on the management aspects of urban
water. Nontraditional techniques and ideas have to be applied to avoid the cronical problems
of old cities.
WASTEWATER TREATMENT
Only the biggest cities in Egypt (about 60 cities) have public sewerage systems. Most of the
networks are overloaded and in poor condition. Sewerage and sanitation facilities were
lagging behind water supply. Recently, the Government of Egypt (GOE) has launched an
ambitious program for constructing new wastewater collection and treatment systems allover
the country. Work undertaken over the last two decades has involved the design of an
extensive wastewater collection system and six major wastewater treatment plants to serve the
population in Greater Cairo. Five of these treatment plants are in operation. The wastewater
treatment technologies employed in these plants are: activated sludge; aerated lagoons; and
wastewater stabilization ponds. They provide secondary treatment to the domestic and
industrial wastewater of about 3,000,000 m3/day generated by a population of 16 million
persons. The daily flow is expected to reach 4,000,000 m3/day in 2025. Considering the
predicted increase in population, urbanization and consequently water consumption, then the
reuse of treated effluents in Egypt is very crucial.
WATER SUPPLY ENHANCEMENT
Innovative supply enhancement measures include new water supplies from new facilities,
reclamation and desalination plants, water transfers, improving existing system operations,
and increases use of groundwater. Reused water can be added to the supply system as either a
new source of water supply or for pollution control (Wilchfort and Lund, 1997). Reused water
has been used in different parts of the world for agricultural and landscaping irrigation,
industrial processes and cooling towers, toilet flushing, groundwater recharge and direct
consumptive use (Marecos et al., 1996). Asano and Madancy (1984) considered that water
reuse is more feasible and cost-effective for nonpotable purposes. In evaluating the cost of
reuse as a water supply source, the cost of treatment, the conveyance system, and operation
and maintenance should be considered (Asano and Mills, 1990).
In Egypt reclaimed water has been used since 1915. An area of about 10,000 acres at AlGabal Al-Asfer, northeast of Cairo, is irrigated with wastewater which receives only primary
treatment (Abdel El-Naim, 1988). During the period 1986-1992, about 71,000 acres were
reclaimed and irrigated by greater Cairo sewage effluents mixed at 1:1 with clean freshwater.
Studies were carried out to irrigate about 80,000 acres in the western delta region at El Bustan
using sewage effluents from Alexandria. There are considerable future plans for irrigation
using reclaimed water (Abu-Zeid, 1993). Future urban wastewater projects include facilities
for advanced treatment, which is still lacking in Egypt. Table 1 presents the estimated
wastewater treatment capacity in Egypt (Abou-Rayan and Djebedjian, 2000).
Table1: Estimated Wastewater Treatment Capacity (million m3/year)
Zone
1997
2025
Greater Cairo
Alexandria
Delta
Upper Egypt
Other Urban Areas
1278
237
949
438
256
2219
412
1648
761
449
Total
3158
5489
Okun (1997) considered that dual distribution systems provide an additional economical water
source and reduce the cost of wastewater disposal. Such systems are in use worldwide; one
system is used for drinking water and another for reclaimed water. They permit more
appropriate use of limited high-quality water sources while exposing the public to little
additional risk. Dual systems are particularly appropriate for urban developments now being
planned, and may prove cost-effective in existing urban areas.
WATER POLLUTION AND HEALTH HAZARDS
Water pollution is a serious problem in the majority of the developing countries. A high
propertion of domestic and industrial effluents are untreated and discharged directly to
watercourses, irrigation canals and drainage ditches (Brikett, 1999). Treated effluents usually
do not meet the stringent standards for disposal to watercourses. This is an acute difficulty
that needs remarkable capabilities and comprehensive efforts to overcome.
In Egypt no guidelines have been adopted but the law 48/1984 prohibits the use of effluent for
irrigation crops unless treated to the required standards of agricultural drainage water. The
irrigation of vegetables eaten raw with reclaimed water, regardless of the quality level, is
forbidden. Some Egyptian standards for discharge of treated wastewater into watercourses are
listed in Table 2, in which biochemical oxygen demand (BOD) is considered the single most
important water pollutant. However, high proportion of urban water in the eastern delta is
untreated and discharged directly to drainage ditches. Health problems arise due to seepage
flow from such ditches of high water levels to groundwater and infiltration into neighboring
irrigation canals.
Table 2: Standard Maximum Measures, mg/l.
Parameter
Non-fresh water ways
Fresh waterways
BOD
Dissolved oxygen
Oils
Dissolved solids
Suspended solids
60
not less 4
10
not more 2000
50
6
5
0.1
500
---
The standards for the reuse of sanitary drainage water and degree of treatment are
summarized in Table 3. The standards are defined for three groups of wastewater: group 1effluent of primary treatment; group 2- effluent from secondary treatment; and group 3- water
that has received advanced treatment.
Table 3. Maximum Criteria for the Reuse of Reclaimed Water and Degree of Treatment in
Egypt
mg/l
Group 1
(Primary)
300
Group 2
(Secondary)
40
Group 3
(Advanced)
20
mg/l
350
40
20
--5
--up to 2,500
up to 5
up to 350
10
1
100
up to 2,000
up to 3
300
5
1
100
up to 2,000
up to 3
300
Parameter
Unit
BOD
Solid
Suspended
Substances
Oils
Intestinal Nemotodes
Fecal Coliform
Total Sodium
Boron
Chlorides
mg/l
cells/l
number/100ml
mg/l
mg/l
mg/l
A recent study has been carried out at Alexandria University to investigate the impact of
effluent disposal on receiving drains for four secondary wastewater treatment plants (TP) and
BOD removal efficiency. Each of the receiving drains is a stretch with the wastewater TP as a
point source of BOD. Brief sample results are presented in Table 4 (personal communication).
Of the four TPs, two use activated sludge and the other two use trickling filters, and their
design capacity ranges from 12,000 m3/day to 90,000 m3/day. BOD concentration in the
effluent of three out of four plants exceeds the maximum of 60 mg/l for discharge to nonpotable surface waters (48/1984 Law). Downstream BOD concentration reflect selfpurification.
Table 4: BOD concentration, in mg/l, showing the impact of effluent on drains
Wastewater
sampling point
Treatment
plant
Damanhour,
Receiving
drain
El-Khairy
Amina
Omer
Deshaoudy
15
472
83
34
9
325
30
13
7
650
77
26
23
217
75
21
Upstream the TP
TP influent
TP effluent
One km downstream the TP
Abou El
Matamir
Samannoud
Kafer ElDawar
The GOE is taking steps to overcome some of the most pressing problems associated with
reusing wastewater by removing the industrial component or treating it thoroughly at the
source, before admitting it into the principal sewage networks or discharging it into the
waterways. An industrial treatment project is currently under way that covers some 200
plants, classified according to their effluents, discharge system and outlets. Those discharging
directly into the Nile subsidiary branches are given the highest treatment priority. Others with
less or indirect impact on the environment or public health are given second or third priority
(Eid, 1988).
Steps have been taken to establish some major pilot projects on the use of reclaimed water for
agricultural production. For example, new sewers of Greater Cairo will be able to treat up to 4
million m3/day, that could irrigate 400,000 acres of desert lands. A pilot project was launched
in Abu Rawash area (Giza) aiming at investigating the environmental impact, with special
emphasis on health aspects, chemical and physical effects on the soil, groundwater reserves,
crops, and on workers and local population. Conditions in the area were monitored for four
consecutive years. Positive and negative effects were recorded. The positive effects include
increased organic matter in the soil from 0.1 to 0.5%, with marked improvement in the soil
properties, nutrient absorption, water holding capacity and cation exchange capacity. The
yield for an experimental crop of maize increased from 700 to 2000 kg/acre. Negative effects
include accumulation of heavy metals in the soil and crops, increased nitrates in groundwater
and health hazards to workers. Cases of hepatitis, dysentery and nematoid infestation and
other diseases were reported over the four years of the investigation (Khalifa, 1997).
WATER CONSERVATION
Water shortages necessitate the development of innovative demand management beside
supply enhancement measures. Water conservation practices have to be adapted to reduce the
effects of water consumption on the environment. Urban water conservation methods include
various forms of rationing such as fixed allotments to customers, percent reduction in supply,
adoption of tiered pricing to control consumption, and rotation of service to customers (Lund
and Reed, 1995).
The major factor affecting the amount of diverted urban water for municipal use is the
efficiency of delivery networks. The efficiency is as low as 50%in many urban areas in Egypt.
Half of the diverted water is almost lost by leakage from the distribution network. Much
attention is given to the rehabilitation of pipelines networks to reduce the enormous
conveyance losses of good quality water. The use of synthetic materials for pipes in water
distribution systems that are resistant to corrosion and wear are rather efficient.
CONCLUSIONS AND RECOMMENDATIONS
Threats of water shortage have induced the development of innovative demand management
and supply enhancement measures. In developing countries, including Egypt, urban water
management faces difficulties, which decelerate the rate of development and create health
hazards. Financing problems arise due to the unbalance between high cost of urban water
projects and funds limitations. Not much in-house expertise is present for planning, plant
design or special equipment design and construction. Adopting a low level of treatment is
desirable, not only from the cost point of view, but also in acknowledgement of the
difficulties of operating complex systems reliably. However, the most appropriate wastewater
treatment is that which will produce an effluent meeting the recommended quality guidelines
both at low cost and with minimal operational and maintenance requirements.
Field practice and consumer preferences seem to support continued growth of the nonpotable
reuse option in future. In this context, dual systems have to be considered among the
alternatives available for integrated water resources management. Nevertheless, notional
guidelines and regulations on wastewater reclamation and reuse have to be established.
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