Transcript COUNTRY PAPER ON REUSE OF LOW QUALITY WATER IN EGYPT

COUNTRY PAPER
ON
REUSE OF LOW QUALITY WATER
IN EGYPT
Agriculture Drainage System
The total agriculture land amounts to 8 million
feddan
The implementation of the National Drainage
Program started in 1970. It included the
widening and deepening of the existing main
open drains, the excavation of new main
drains ,the construction of new pumping
stations and the rehabilitation of old ones.
It included also, the installation of subsurface
drainage systems of laterals and collectors
The average field drainage depth is 1.35 m
and the minimum depth of water levels in the
main drains is 2.5m.
The total target of the surface drainage is 7.2
million feddan, of which 4.9 million feddan are
in the Nile Delta and 2.3 million feddan in
Upper Egypt.
Agriculture drainage Reuse
The drainage water in Upper Egypt is
pumped or flows by gravity back to the Nile.
In the Delta, the network of open drains
discharges their flows mainly into the
Northern Lakes or the sea. The total length of
Nile Delta drains is over 16,000 km long.
Three types of reuse practice can be
distinguished: natural, official and non-official
reuse
Natural reuse of drainage water occurs where
rivers or canals act as a drain for hydrologic
basin aquifer systems. Natural reuse is
largely non-controllable except by modifying
the amount of recharge that occurs, i.e.,
reduction of deep percolation from irrigation
Official reuse is the practice of including part
of drainage water flow in the quantity of
irrigation water delivered by the irrigation
system. Physically, official reuse occurs
through lifting specific amounts of drainage
water from drains and blending the water with
higher quality canal or river water. Official
reuse may also include extracting moderately
saline groundwater for supplementing
irrigation water supplies.
Non-official reuse is practiced by
individual farmers who decide when and
how much drainage water will be used
for supplementing their irrigation water
supply
Reuse as a Policy
Dr. Mahmoud Abu Zied, Minister of Water
Resources and Irrigation, Egypt; stated that”
In terms of increasing the overall system
efficiency, the drainage reuse pays back
much faster and at much less cost than the
irrigation improvement. This justifies the
adoption of the drainage reuse strategy on
the short term”
National Agriculture Projects that
depend on the reuse of drainage
water.
The purpose was to use as much drainage
water as possible especially for the irrigation
of large land reclamation projects in the
eastern and western parts of the Delta.
Three projects of this kind were designed
AL-SALAM CANAL PROJECT
Al-Salam Canal is designed to be fed from
the Damietta Branch upstream of Farskour
Dam with fresh water while supplemented
with drainage water from the Lower Serw
pumping station and Bahr Hadous drain near
its outfall. At this point, the drain contains the
collection of drainage water from all the
catchments served namely Nizam , BeniEbeid and Erad .
The average yearly discharge of the Lower
Serw pumping station is about 600 x 106 m3,
and that of Bahr Hadous drain is about 2 x
109 m3. These bring the available drainage
water total to 2.6 x 109 m3 / year.
The average salinity measured at Lower
Serw pumping station is around 1 000 ppm,
and that measured at Bahr Hadous outfall is
about 1 400 ppm. The weighted average of
both waters is 1300 ppm. When this is mixed
with fresh water at a ratio of 1:1 the salinity of
the mixture is expected to be in the
neighborhood of 800 ppm which is
reasonable, given that the water is going to
be used for the irrigation of sandy soils.
OMOUM DRAIN
PROJECT
The canal serves an area of reclaimed lands
of about 500,000 fed. and passes a discharge
of 5.0 x 109 m3 / year. The quantity of
drainage water to be used in the project is
about 1.0 x 109 m3 / year and has an average
salinity of 1 800 ppm. The expected salinity of
water after mixing will be in the margin of 800
ppm.
Drain No. 1 and 2
Those drains are located on the far north of
the Middle Nile Delta region
The collective discharge of the two pumping
stations is about 900 x 106 m3 / year at an
average salinity of 1000 ppm
Following the completion of the construction
of the above three projects, an extra quantity
of 3.40 x 109 m3 of drainage water will be
used for irrigation which brings the total to
7.60 x 109 m3 (4.2 x 109 m3 are already reused every year at different other drains in
western / eastern / middle delta and
Fayoum).
current status of reuse of drainage
water
Reuse of Drainage Water in the Nile Delta During 1995/2003
Year
Eastern Delta
Middle Delta
Western Delta
Total Reuse
Q
(mcm)
EC
Q
(mcm)
EC
Q
(mcm)
EC
Q
(mcm)
EC
1995-96
1745.9
1.89
1814.6
1.79
705.9
1.42
4266.3
1.77
1996-97
1843.2
1.94
1947.9
1.85
642.5
1.31
4433.6
1.81
1997-98
1736.3
1.66
1801.3
1.77
632.4
1.35
4170.1
1.66
1998-99
2126.9
1.48
2168.3
1.52
738.3
1.07
5033.5
1.43
1999-00
1661.8
1.64
1891.4
1.64
1183.6
1.97
4736.8
1.72
2000-01
1830.2
1.57
1958.8
1.76
1058.3
1.92
4847.3
1.72
2001-02
2026.5
1.74
2199.8
1.67
1062.8
1.76
5289.1
1.71
2002-03
2329.3
2.00
2082.4
1.90
875.6
1.76
5287.4
1.92
Treatment Technology
The total quantity of reused treated
wastewater in Egypt was about 0.7 BCM in
1995/96 of which 0.263 BCM is biologically
treated while the rest (0.437 BCM) is only
primary treated. The quantity of the reused
wastewater is approximately 10% of the
potable water consumption
Potential of Treated
Sewage Reuse
In Greater Cairo, there are six wastewater
treatment plants, with a total capacity of
approximately 27 million m3/day. All of which
will eventually be treated to a secondary
standard. With a current combined treatment
capacity of this quantity of effluent is
potentially sufficient to irrigate about 100,000
feddans
Drainage water quality criteria for
irrigation purposes in the Nile Delta,
Egypt
Salinity
(dS/m)
of
drainage
water Restriction on use for irrigation
< 1.0
used directly for irrigation
1.0 – 2.3
mixed with canal water at ratio 1:1
2.3 – 4.6
mixed with canal water at ratio 1:2 or 1:3
> 4.6
Not used for irrigation
Maximum Possible drainage
water reuse in Nile Delta
(mcm)
Region
Available Drainage
Water
Currently Reused
Possible to be
reused
Eastern Delta
4083.65
2049.89
1519.02
Middle Delta
5849.14
2007.73
2881.06
Western Delta
3819.15
1123.56
2384.33
Total
13751.94
5181.18
6784.41