Sustainable Reuse of Treated
Wastewater for Agriculture
Ahmed Al-Busaidi, Mushtaque Ahmed and
Baby Shaharoona
College of Agricultural & Marine Sciences, Department of
Soils, Water and Agricultural Engineering, Sultan Qaboos
University, P.O. Box 34, Al-Khoud123, Muscat, Oman
ahmed99@squ.edu.om
Global Water Resources
• World population
food production
limited fresh water resources
Municipal Wastes Management
3R Approach
Water Balance (Deficit- Excess)
Water Balance in the Sultanate
(MCM/Yr)
390
1267
Supply
Demand
1657
Deficit
Wastewater Treatment Plants > 402
Muscat STP water
5
PARAMETER
Inorganics
Standards for
Wastewater
Reuse (mg/l)
Limitations:
Contains
some Heavy
Metals
Monitoring is
Required
Aluminum (as Al)
Arsenic (as As)
Barium (as Ba)
Beryllium (as Be)
Boron (as B)
Cadmium (as Cd)
Chloride (as Cl)
Chromium (total as Cr)
Cobalt (as Co)
Copper (as Cu)
Cyanide (total as CN)
Fluoride (as F)
Iron (total as Fe)
Lead (as Pb)
Lithium (as Li)
Magnesium (as Mg)
Manganese (as Mn)
Mercury (as Hg)
Molybdenum
Nickel (as Ni)
Ammonical (as N)
Nitrate (as NO3)
Phenol (total)
Phosphorus (total P)
Selenium (as Se)
Silver (as Ag)
Sodium (as Na)
Sulphate (as SO4)
Sulphide (total as S)
Vanadium (as V)
Zinc (as Zn)
STANDARDS
Class A
5
0.100
1
0.100
0.500
0.01
650
0.050
0.050
0.500
0.050
1
1
0.100
0.070
150
0.100
.001
0.010
0.100
5
50
0.001
30
0.020
0.010
200
400
0.100
0.100
5
Class B
5
0.100
2
0.300
1
0.010
650
0.050
0.050
1
0.100
2
5
0.200
0.070
150
0.500
0.001
0.050
0.100
10
50
0.002
30
0.020
0.010
300
400
0.100
0.100
5
‫‪Date palms in Oman‬‬
‫واﻗﻊ زراﻋﺔ اﻟﻨﺨﻴﻞ ﻓﻲ اﻟﺴﻠﻄﻨﺔ‬
‫الترتيب‬
‫المحافظة‪/‬المنطقة‬
‫‪Area‬‬
‫عدد النخيل *‬
‫‪No. of Date‬‬
‫‪palms‬‬
‫متوسط انتاج‬
‫النخلة )كجم(‬
‫)‪X (Kg‬‬
‫كمية انتاج التمر‬
‫)طن(‬
‫)‪Pro. (Ton‬‬
‫النسبة المئوية‬
‫لالنتاج ‪%‬‬
‫‪1‬‬
‫محافظة مسقط ‪A‬‬
‫‪11573.92‬‬
‫‪34.17‬‬
‫‪338674‬‬
‫‪4.42‬‬
‫‪2‬‬
‫منطقة الباطنة ‪B‬‬
‫‪111407.06‬‬
‫‪39.55‬‬
‫‪2817190‬‬
‫‪42.55‬‬
‫‪3‬‬
‫محافظة مسندم‪C‬‬
‫‪4521.00‬‬
‫‪31.31‬‬
‫‪144381‬‬
‫‪1.73‬‬
‫‪4‬‬
‫منطقة الظاھرة ‪D‬‬
‫‪27136.37‬‬
‫‪49.29‬‬
‫‪550545‬‬
‫‪10.36‬‬
‫‪5‬‬
‫المنطقة الداخلية ‪E‬‬
‫‪54497.28‬‬
‫‪57.22‬‬
‫‪952428‬‬
‫‪20.81‬‬
‫‪6‬‬
‫المنطقة الشرقية‪F‬‬
‫‪43878.51‬‬
‫‪31.41‬‬
‫‪1397010‬‬
‫‪16.76‬‬
‫‪8‬‬
‫محافظة ظفار‪G‬‬
‫‪7‬‬
‫محافظة البريمي ‪H‬‬
‫‪132.43‬‬
‫‪8704.10‬‬
‫‪6.19‬‬
‫‪21388‬‬
‫‪0.05‬‬
‫‪32.84‬‬
‫‪265012‬‬
‫‪3.32‬‬
‫‪6486628‬‬
‫‪40.37‬‬
‫‪261850‬‬
‫‪100.00‬‬
‫المجموع ‪Total‬‬
Result and discussion
Heavy metals translocations in location 1
12
10
Mn
GW
Fe
12
10
4
Conc. (mg/l)
Conc. (mg/l)
6
Cu
Cr
Cd
Pb
8
6
Cu
Cd
Pb
Ni
2
Zn
Cr
4
2
B
TWW
Fe
Zn
8
Mn
Ni
B
0
0
Soil
Plant leaves Plant fruits
Sample location
Soil
Plant leaves Plant fruits
Sample location
Result and discussion
Heavy metals translocations in location 2
14
Conc. (mg/l)
10
8
6
GW
Mn
Fe
Zn
Cu
Cr
Cd
Pb
Ni
B
45
40
35
Conc. (mg/l)
12
50
4
2
TWW
Mn
Fe
Zn
Cu
30
25
Cr
Cd
20
Pb
15
Ni
10
B
5
0
0
Soil
Plant leaves
Sample location
Plant fruits
Soil
Plant leaves
Sample location
Plant fruits
Result and discussion
Heavy metals translocations in location 3
12
Conc. (mg/l)
10
8
6
4
2
Mn
Mn
GW
8
Fe
Zn
7
Zn
Cu
6
Cu
5
Cr
Fe
Conc. (mg/l)
14
Cr
Cd
Pb
Ni
B
Cd
Pb
3
Ni
2
B
1
0
Soil
4
TWW
Plant leaves Plant fruits
Sample location
0
Soil
Plant leaves Plant fruits
Sample location
Wheat Irrigated by Treated Wastewater
Result and Discussion
Plant parameters as affected by different irrigation methods
and water qualities
40
35
FW Furrow
FW Drip
TW Furrow
TW Drip
30
Value
25
20
15
10
5
0
Height (cm)
Spike Length
(cm)
1000 Grain
Weight (g)
Spike Yield (t/ha) Biological Yield Straw Yield (t/ha)
(t/ha)
Plant parameter
Result and Discussion
Nutrients (mg/L) present in wheat grains
variables
FW Furrow
FW Drip
TW Furrow
TW Drip
Na
Ca
Mg
K
Zn
Cu
Mn
Fe
Cd
Ni
Si
0.47
105.56
34.28
10.29
0.24
0.11
1.10
0.81
0.06
0.27
0.06
0.14
105.80
35.88
4.57
0.17
0.14
0.66
0.76
0.08
0.49
0.07
1.342
109.25
39.43
8.90
0.21
0.11
0.74
0.81
0.09
0.27
0.06
0.78
104.60
35.41
9.14
0.10
0.10
0.68
0.71
0.06
0.27
0.05
Conclusion:
* Wheat can be irrigated by treated wastewater
* More Studies are needed
Mitigating Environmental Risks of
Wastewater Reuse for Agriculture
Vegetables irrigated by Treated
Wastewater, Groundwater amd
Mix of both Waters
 1st Season
Result and discussion
 Soil chemical properties
0.4
50% TWW
100% GW
75% TWW
100%TWW
0.35
Concentration 0.3
0.25
0.2
0.15
0.1
0.05
0
Fe
B
Ba
Pb
Micro element
Co
Cr
 1st Season
Result and discussion
 1st Season
Result and discussion
 Crop physical properties
Maize Weight (g)
Okra Weight (g)
1800
16
1600
14
1400
12
10
1000
Weight
Weight
1200
800
8
6
600
4
400
2
200
0
0
50% TWW
100% GW
75% TWW
Treatment
100%TWW
50% TWW
100% GW
75% TWW
Treatment
100%TWW
 1st Season
Result and discussion
 Crop chemical properties
maize
3
2
50% TWW
1.5
100% GW
1
75% TWW
100%TWW
0.5
0
Mn Cd Cu Fe Zn
B
Al Ba Cr Co Pb Ni
Concentration Concentration 2.5
sweet corn
1.800
1.600
1.400
1.200
1.000
0.800
0.600
0.400
0.200
0.000
50% TWW
100% GW
75% TWW
100%TWW
Mn Cd Cu Fe Zn
Ti
okra
3.5
50% TWW
100% GW
75% TWW
100%TWW
0.5
Concentration Concentration 2
1
Ba
Cr Co Pb
Ni
Ti
Sweet melon
3
1.5
Al
Micro element
Micro element
2.5
B
2.5
50% TWW
2
100% GW
1.5
75% TWW
1
100%TWW
0.5
0
0
Mn Cd Cu Fe Zn
B
Al Ba Cr Co Pb Ni
Micro element
Ti
Mn Cd Cu Fe
Zn
B
Al
Ba
Micro element
Cr
Co Pb
Ni
Ti
Mitigating Environmental Risks of
Wastewater Reuse for Agriculture
3rd Season
In Progress
Knowledge Gaps
 Studies on plant uptake of PPCPs are few and small in scale.  Most studies were carried out under hydroponic or greenhouses conditions.
 Accumulation of PPCPs in vegetables irrigated with treated wastewater under field conditions is unknown.
In Progress
In Progress
Usage of Treated Wastewater for
Bio-fuel Production
Definition of Biofuels
fuels derived from biomass: plant material, crop
energy, or agricultural and forestry wastes and byproducts used as energy source.
Examples
Sunflower oil
Coconut oil
Palm oil
Rapeseed oil
Why use Biofuels
Fossil fuel:
 Limited
 Carbon dioxide
 Production
 Rural economy
Bio-fuel:
 Renewable, Biodegradable
 Efficient
 Engine Friendly
 Healthier
 Carbon Neutral
 Job generation
Global warming
Converting food crops
into biofuel “is a crime
against humanity.”
SO
What to do?!!!
What Is Jatropha (a biofuel crop)?
Jatropha (Jatropha Curcas) is an excellent biofuel crop
which has many other advantages over existing crops.
The hardy Jatropha is resistant
to drought and pests, and
produces seeds containing up to
40% oil. When the seeds are
crushed and processed, the
resulting oil can be used in a
standard diesel engine, while
the residue can also be
processed into biomass to
power electricity plants.
Growth of Jatropha after transplanting
(Winter Time)
Treated wastewater
freshwater
saline water (3 dS/m)
Thank
You