EFFECT OF LASER LAND LEVELING ON WATER SAVEING IN
EGYPTIAN AGRICULTURE
Dr. Ahmed El-Behery* Dr. Afaf Mohamed** Dr. Rania K. Ibrahim***
ABSTRACT
Water is a key input to sustained economic growth and productivity in every sector of economy. It is of particularly of critical significance in agricultural production and processing, upon which as much as 40 percent Egypt's GDP depends. Agricultural production relies heavily on irrigation, which uses about 77 percent of Egypt's total water supply, primarily from the Nile River. Water policies that promote growth in agricultural production and processing serve to directly increase the incomes of farmers, as well as to create jobs and provide increased economic security throughout the society. Egypt is endowed with vast land resources. However, without water, this land would be unproductive. The source of Egypt's irrigation water is almost exclusively the Nile River, of which Egypt is currently utilizing a fixed share (55.5 Billion meters cube) yearly. According to the FAO, the standard hydrological index of water scarcity is defined as 1,000 cubic meters of water per capita. Anything below that amount constitutes a condition of "national water scarcity". At the current population level (75 million), average annual per capita water availability in Egypt is 812 cubic meters year 2006. This is expected to drop to 700 cubic meters per capita by the year 2010.Unless timely policy measures are taken to cope with this trend, water will likely become a severe constraint to Egypt's economic development, particularly in the agriculture sector.
As part of the Government of Egypt's efforts to promote improve water conservation and management in agriculture sector, the Ministry of Agriculture and Land Reclamation (MLAR) and the Ministry of Water Resources and Irrigation (MWRI) are working together to reduce the amount of water applied to agricultural crops while maintaining high levels of crops productivity and improving farm income. During the last three decades MLAR is adopting several techniques to optimize water applied to each crop, Laser land leveling technique one of the practices has been introduced and highly appreciated by farmers. Field which is leveled by laser reduces water use on sugarcane, rice, wheat, and vegetables crops by between 20-30%, and energy saving by between 10 – 15%. The yield increased by between 10 – 15 %. Other important benefits are derived from this technique. There are; improved drainage; improved fertilizer efficiency; improve weed control; and considerable time and cost saving associated with irrigation.
Introduction
Egyptian economy has traditionally relied heavily on the agricultural sector for food, fiber and other products. The agricultural sector provides the livelihood for about 40% of the inhabitants and employment for about 34% of the total employment and labor force. In addition, agriculture contributes about 20% of the gross domestic product (GDP) and about 20% of the total exports and foreign exchange earning.
* Senior Researcher, Agricultural Engineering Research Institute (AENRI), ARC, MALR, Egypt.
** Associate Professor, Economic Department, Faculty of agriculture,Damanhour University., Egypt.
*** Researcher, Agricultural Engineering Research Institute (AENRI), ARC, MALR, Egypt.
The demand for agricultural products is increasing due to population growth and the need for more export earning. The country plan is to bring to cultivation a total of 3.4 millions acres from the desert area up to the year 2017.This requires more emphasis on agricultural research to identify agricultural–sector constraints and to solutions through appropriate technologies especially in the newly cultivated and reclaimed areas. Meanwhile, Delta and Nile valley lands require adopted technology to save water and increase land unit productivity.
The Nile is the major source of water in Egypt. The Nil's water agreement between Egypt and Sudan in 1959 allocated about 55.5 billion's meter cube yearly. Surface and improved surface irrigation are the main methods used in old land. In the newly reclaimed land the use of pressurized system such as sprinklers and drip irrigation is a must in newly reclaimed land, and surface irrigation is prohibited by low. On 1978 Laser land leveling technology has been introduced at Noubaria Mechanization Farm as a pilot demonstration the field size was 30 acres, several efforts has been spent to convenes growers to level there field using leaser leveling, but all efforts has been failed. On 1984 National Mechanization Project took the initiative and introduced Laser Land Leveling technology in upper Egypt region, where farmers cultivate Sugar-cane which consume a lot of water, the field surfaces were uneven, this tend to some what over irrigation. Since then the growers has noticed the technology benefits, meanwhile, this technology introduced to Lower Egypt, were growers cultivate Paddy rice. On 1996 private contractors has realized the potential and market demand of Laser technology on commercial basis, this was starting point and spreading laser leveling technology. El- Hadad et al (1984) indicated that earth work volume between 22 meter cube per feddan were moved (an average of 41 meter cube per feddan was moved). Although check surveys were carried out. Mcclung and Berger (1986) mentioned that in order to determine when field is leveled or it needs leveling, certain criteria must be set, which may be based mainly on two different parameters, precision land leveling index, and volume of cut required per feddan. El-Hamamy (1988) showed that surface irregularities exceed by far the accepted tolerance allowed in surface irrigation deviations reported from zero level or slightly inclined fields (0.03-0.05) vary between 8-23 cm in Nile Delta and 7-35 cm in Upper Egypt. This deviation occurred in fields leveled, smoothed and prepared for planting different crops. Deviation were higher near the field edges and at the corners.
MATERIAL AND METHODS
Light Amplification of Simulated Emission of Radiation (LASER) which was utilized in agriculture sector, the unit consists of transmitter powered by 12 volt battery. Receiver move up and down controlled by tractor hydraulic system and solenoid valves, control box powered by tractor electrical system. Transmitter is mounted on wood stand, receiver mounted on top of four wheels field leveler three meter width, and control box mounted on tractor next to tractor control panel. The laser leveling process starts by field survey for determining field surface slope, as well as surveying the high and low spots of field surface and draw survey grid, to determined dirt cut and fill amount. The ideal condition to operate laser system economically, the difference between high and low spots shouldn't be more than 15 cm. The function of laser unit starts when the receiver on the field leveler receive a ray from transmitter which based on one corner in the field , then the receiver transform this ray into signals to the control box mounted on the tractor. One transmitter can serve 2-3 tractors efficiently, therefore, leveling cost per feddan is economical, the average time to level one feddan between 2-3 hours, laser land leveling needs to be repeated in the same field every four years.
Based on (MLAR) and (MWRI) strategic plan to reclaim 3.4 million feddan up to 2017, in order to narrow food gap to meet daily food demand. Due to the population increase yearly in Egypt, Egyptian Government is encouraging farmers to produce horticulture and field crops for local market and export, both ministries encourage farmers to use different technology to save water, one of this technology was laser land leveling. Several field trips conducted in Behera Governorate, to meet farmers leveled their fields by LASER technology.
Electrical Mast Transmitter
Receiver Control Box
RESULTS AND DISCUTION
Average Water Consumption for Sugarcane :Table (1)
Irrigation system
Water consumption (m3/fed./year)
Difference from traditional method (m3/fed./year)
% Difference
Surface irrigation
12400
--
Drip irrigation
8121
4279
34.5
Sprinkler irrigation
11438
9620
7.8
Developed surface irrigation
8474
3926
31.7
ٍSource: Sugar Council Crops Report 2008
The data listed in table (1) show that the different irrigation methods on Sugar cane cultivation and water use efficiency for each system. Drip irrigation system, water could be saved up to 34.5 %, but sugar cane grower are reluctant to install this system concerning economical cost and rotten maintenance, meanwhile, during harvesting season require special care to dismantle drip irrigation network. Improved surface irrigation system is the most adopted system for water saving, up to 31.7 %, and the third irrigation system was sprinkler irrigation could save about 7.8 % of irrigation water
Table (2): Comparison Between Traditional Cultivation and Laser Land Leveling Cultivation
Crop
Land leveling system
Water applied (m3/fed.)
Dif. , %
Traditional leveling
1585
Laser land leveling
1310
- 17.35
Maize
2620
2585
- 1.34
Maize intercropping with soybean
2390
2250
- 5.86
Soybean
2210
2150
- 2.71
Soybean intercropping with maize
Source: Ibrahim, R. K. (2003). Precision Land Leveling needs in relation to water management and on-farm energy under agricultural intensification conditions. M. Sc. (thesis), National Institute of Laser Enhanced Science (NILES), Cairo Univ., Egypt.
Table (2) indicate the amount of water could be saved on field leveled by laser system, and cultivated by solid crops of Wheat, Maize, Soy bean crops. The amount of water saved on wheat crop was 17.35 %, followed by Maize crop the amount of water saved was 1.34%, the amount of water saved on Soy-bean crop was 2.71 %, but the inter cropping of Maize with Soy bean was5.86 %, and inter cropping Soy-bean with Maize was 5.86 %.This obtained data under the study condition at Sids research station ARC, in Middle Egypt.
Table (3) stated that, the total cultivated area of crops pattern is 13595 million feddan, include old and newly-reclaimed land, the total cultivated area of winter crops is 6.55 million feddan, the total cultivated area of summer crops is 6.44 million feddan, and 0.61 million feddan in Nili season. If all above mention cultivated area of crops pattern could be leveled by leaser system. On table (4) Egypt could save about 5.074 billion cubic meters of water per year. During winter season the amount of water could be saved is 1.556 billions cubic meters, which is an equivalent 30.69% of total amount of saved water, meanwhile, during summer season the amount of water could be saved is 3.326 billion cubic meters, which represent 65.55% of total amount of saved water yearly. and in Nili season the amount of water could be saved is 0.191 billion cubic meter, which is an equivalent 3.70% of total amount of saved water.
The above mentioned figures based on assumption of saving 10% of total amount of water which is allocated at Aswan Dame for irrigation yearly. This amount of water if all cultivated areas leveled by laser system. Therefore, this amount of saved water could be used on newly-reclaimed land, in order to grow export crops, which is source of hard currency, or grow Wheat, Maize, and oil crops, in order to reduce part of food gape, and secure food self sufficiency.
Table (3): Water Requirements for Crop Pattern Deliver at Aswan Dam.
Area
(1000 fed.)
Water requirement at Aswan (m3/fed.)
Average
North Egypt
Middle Egypt
Upper Egypt
Winter Crops:
Clover
2052.79
3407
3806
4785
3999.33
Wheat
2985.29
2034
2252
2789
2358.33
Barley
247.67
1752
1761
2275
1929.33
Bean
221.27
1583
1702
2234
1839.67
Lentil
2.53
1779
1938
2530
2082.33
Fenugreek
15.18
Cheek pea
14.95
1705
1833
2406
1981.33
Libonies
3.52
Flax
16.35
1620
1743
2322
1895.00
Onion
108.72
2216
2485
3190
2630.33
Garlic
17.01
1615
1970
2534
2039.67
Sugar beet
167.33
2626
2943
3668
3079.00
Potatoes
141.86
2213
2470
3198
2627.00
Tomatoes
214.62
2043
3357
2675.33
Other vegetables
288.47
2664
2796
2989
2816.33
Other crops
52.35
2075
2117
2279
2157.00
Sub-Total
6549.90
32694
36082
45320
38032
2255
2833
2377
Summer crops:
1790.68
3507
4027
4599
4044.33
Sorghum
351.30
2130
3544
4074
3249.33
Rice
1459.05
9202
10122
11134
10152.67
Yellow maize
149.58
4103
4687
5554
4781.33
Pea nut
148.02
4697
5594
6613
5634.67
Sesame
66.86
3014
3471
4008
3497.67
Soya bean
20.08
3344
3885
4484
3904.33
Sunflower
31.46
2622
3063
3494
3059.67
11.20
4497
5272
5799
5189.00
113.28
2600
2990
3584
3058.00
215.46
3304
4155
5197
4218.67
761.97
3583
4211
4816
4203.33
286.09
2830
3145
3156.33
Sugar cane
321.38
8719
9916
12033
10222.67
cotton
656.59
3977
4465
5090
4510.67
56.69
8303
9482
11472
9752.33
Sub- Total
6439.68
70432
82029
95445
82635.00
4402.00
5126.81
5965.31
5164.69
Nilli Crops:
276.59
2872
3234
3917
3341.00
9.44
2061
2536
3176
2591.00
0.49
5904
6494
7143
6513.67
40.63
1653
1854
2313
1940.00
6.44
2621
3861
4768
3750.00
45.53
2027
2078
2324
2143.00
65.30
2940
3724
4626
3763.33
92.53
2318
2397
2427
2380.67
68.76
1884
2024
1930.67
605.69
24280
28062
32718
28353.33
Total
13595.26
2697.78
3118.00
3635.33
3150.37
Source: Eid, et al. (1999 and 2002), personal contact.
Table (4): Expected Amount of Saved Water by Using Laser Land Leveling
Crops
Area (1000fed.)
Average Water Requirements
10% of Saved waterm. cube
ُExpected amount of saved water m. cube
Egyptian Clover
2052.8
399.93
820978.46
2985.3
235.83
704029.90
247.7
192.93
47783.72
221.3
183.97
40706.38
2.5
208.23
526.83
15.2
2792.62
15.0
198.13
2962.09
Lupine
3.5
732.98
16.4
1895
189.50
3098.33
108.7
263.03
28596.95
17.0
203.97
3469.48
167.3
3079
307.90
51520.91
141.9
2627
262.70
37266.62
214.6
267.53
57417.93
288.5
281.63
81242.67
52.4
2157
215.70
11291.90
6549.9
237.70
1556913.61
1790.7
404.43
724210.08
351.3
324.93
114148.96
1459.1
1015.27
1481325.32
149.6
478.13
71519.13
Pea- nut
148.0
563.47
83404.39
66.9
349.77
23385.42
20.1
390.43
7839.89
31.5
305.97
9625.72
11.2
5189
518.90
5811.68
113.3
3058
305.80
34641.02
215.5
421.87
90895.46
762.0
420.33
320281.14
286.1
315.63
90299.44
Sugarcane
321.4
1022.27
328536.17
656.6
451.07
296166.08
Alf- Alfa
56.7
975.23
55285.96
6439.7
516.47
3325900.25
Nile Crops:
276.6
3341
334.10
92408.72
9.4
2591
259.10
2445.90
0.5
651.37
319.17
40.6
1940
194.00
7882.22
6.4
3750
375.00
2415.00
45.5
2143
214.30
9757.08
65.3
376.33
24574.54
92.5
238.07
22028.34
68.8
193.07
13275.29
605.7
315.04
190821.06
13595.3
1069.21
5073634.92
Source: Table (3&4) Arab Organization For Agricultural Development 2008.
Economic Affair Sector, Ministry of Agriculture, 2005 and Foreign Trade Reports, 2008.
Table (5): Cultivated Area and Water Requirements of Agricultural production for Export and Import Strategic Crops for Local Consumption.
Cultivated Area for
Water quantity required
Net return value from One unit of water in US $
Export
Import
Difference
10.72
2096.35
-2085.63
25286.97
4943896.81
0.25
1.88
Beans
4.99
273.49
-268.50
9179.95
503131.35
0.37
0.20
1.45
146.30
-144.85
3010.94
304639.25
0.15
0.14
25.30
0.00
66537.47
0.47
Cotton
254.02
98.90
155.12
1145781.21
446094.61
0.11
Sugar
48.55
239.65
-191.10
149486.03
737882.58
0.18
0.19
Potato
39.06
7.26
31.80
102615.23
19077.15
0.75
2.43
Tomato
1.00
2666.67
1.41
Paddy Rice
265.16
0.73
264.43
2692114.59
7402.23
0.12
0.22
Pea-nut without cover
33.91
0.06
33.85
191064.26
313.73
0.05
7.49
19.18
-11.69
26184.74
67086.46
Sunflower’s oil
266.23
-266.23
814576.05
0.09
Maize (seeds &oil)
4.46
1551.68
-1547.22
18601.73
7397065.25
0.33
0.10
711.40
5457.99
-4746.59
4492284.30
18201274.70
Table (5) indicate that, the calculation of economic rate return unit per water unit, Government of Egypt plan to increase cultivation fresh vegetables for of season export to EU especially, and some Arabian Countries, the Tomato, Potato, Onion, Melon, and cut flowers, those crops has high efficiency of water consumption, at the sometime, the comparative advantage in the international markets. The economic return per water unit in US$ per cubic meter water is 1.41,075, and o.47 for tomato, potato, and onion consecutively. Meanwhile, the imported strategic crops, such as wheat, rice, and broad-bean, has more water use efficiency per water unit. The economic net rate of return per water unit in US$ for those crops are 1.88, 0.33, and 0.20 consecutively per cubic meter water. Also, Egypt import sugar, but newly reclaimed land is appropriate for sugar-beet cultivation, at the same time the economic net return is 0.19 US$ per cubic meter water, Therefore, the imported strategic crops is negative effect on Egyptian trade balance, due to this analysis, Egypt should expand land reclamation, and encourage farmers to save water, in order to cultivate certain crops according to alternative crops pattern, which has market demand and priority for food security.
CONCLUSION
During the last three decades MLAR is adopting several techniques to optimize water applied to each crop, Laser land leveling technique one of the practices has been introduced and highly appreciated by farmers. Field which is leveled by laser reduces water use on sugarcane, rice, wheat, and vegetables crops by between 20-30%, and energy saving by between 10 – 15%. The yield increased by between 10 – 15 %. Other important benefits are derived from this technique. There are; improved drainage; improved fertilizer efficiency; improve weed control; and considerable time and cost saving associated with irrigation. Meanwhile, saved water could be used on cultivation crops for export, and obtain hard currency, or produce crops for local consumption, and reduce food gaps.
REFERENCES
Agricultural Engineering Research Institute and Italian Trade Center In Cairo, Agricultural Sector Survey In Egypt The Recent Situation Report, February, 2007 pp 30-40.
Eid, H. M., S. M. El-Marsafawy and N. G. Ainer (1999),Estimation of consumptive use and water requirements for the new lands in Egypt . Third conf. on forum irrigation and agriclimatolog – Jan. 25-27No53.
Eid, H. M.: Samia M. El- Marsafawy; M. M. Ibrahim and M.M. Eissa (2002). "Estimation of water needs for orchard trees in old lands".
El-Haddad, Z.; A. Araby and J. A. McClung, (1984). A Preliminary Study of Precision Land Leveling Service. Agricultural Research Center, Ministry of Agriculture, Cairo Egypt. Activity Report No. 12.
El-Hammamy, A. A. (1988).Precision Land Leveling an Effective Tool for On-Farm Water Management. First Conf. of Irrigation Improvement, Ministry of Public Works and Water Resources, Cairo, Egypt pp.7-15.
El-Sahrigi, A. F; S. I. El-Khatib; and A. A. El-Behery. (2002) Arab Universities Journal of Agricultural Sciences, Ain Shams Univ., Cairo, 10 (1), 59-71, 2002.
Ibrahim, R. K. (2003). Precision Land Leveling needs in relation to water management and on-farm energy under agricultural intensification conditions. M. Sc. (thesis), National Institute of Laser Enhanced Science (NILES), Cairo Univ., Egypt.
McClung J. A. and L. Berger (1986). A review of Land Leveling Research under-taken by the Egyptian Agricultural Mechanization project. The International Agricultural mechanization Conference, Agricultural Research Center. Ministry of Agriculture, Cairo, Egypt, pp399-419.
Module No. 4: How to Help Farmers when Deciding to Improve their Water Distribution within One Single Plot Via Precision leveling, Egyptian-German On-Farm Management Project (OFWMP), Extension Sector, Ministry of Agriculture and Land Reclamation. Cairo, September 2005. pp 4-5.
Low Cost Sewage Wastewater Treatment Station for Villages and Remote Communities
Ahmed A. EL Behery1, Joachim Kruger2, Ahmed M. Kassem3, Afaf M. Abd El Moneim4
Figures and Tables:
Applying a Subterra System in treating Nile Cruise waste water in Luxor, Egypt
- Influent: domestic waste water from Nile cruisers and restaurant wastewater
- Pretreatment tank, volume: 200 m³
- Subterra station for 250 p.e.; Total surface area Subterra beds: 750 m²
- Effluent into irrigation pond for
Agricultural area
- Sedimentation tank, volume: 140 m³
Nile river
Schematic diagram for Luxor Station
Effluent
Figure 1: Flow chart of a typical Subterra-station
Figure 2: Polyethylene Liner
Figure 3: Reed Plants Roots
Influent
Reed plants
Reed roots (Rhizomes):
- Ensure hydraulic quality of the substrata
- Transporting Oxygen
- Offers habitat for microorganisms
Microorganisms purifying the waste water
Figure 4: Cross Section in Subterra Reed Bed
The Subterra reed bed consists of different layers of sand and gravel
Solar energy is used to operate the pumps
Table (1): The performance results of Luxor Station.
Criteria
Influent Values
Effluent Values
Authorized Limits
PH
7.1
7.5
6 – 9
COD
373 mg/l
15.3 mg/l
80 mg/l
BOD5
226 mg/l
<3 mg/l
40 mg/l
Dissolved O2
0 mg/l
4 mg/l
> 4
NH4-N
21.8 mg/l
0.4-5mg/l
NO3-N
40-70mg/l
E.Coli / 100 cm3
1,500,000
3500
5000
Coli form
2.06x104
102-104
Total Solids, TS
914 mg/l
818 mg/l
2000 mg/l
Total Suspended Solids, TSS
856 mg/l
14 mg/l
Figure 5: COD Influent & Effluent Values at Luxor Station
Table ( 2 ):The percentage of the construction.
ITEM
Percent Value of Total Construction Cost
Materials (P.E, Sand, Gravel ,Man holes, Valves, Pumps….ect )
16.79
Erection labors costs
8.83
Transport
4.52
Excavation
1.73
Accommodation
1.57
Expenses
0.36
Irrigation Pipes
31.98
Design
9.59
Sub total
65.79
Bank interest rate
5.92
Taxes
15.13
Over head
13.16
Total Fixed Cost
98.45
Electricity
14.63
Labor
73.17
Repair & Maintenance
12.20
Total Variable Cost
1.55
Total Fixed & Variable Cost
100.00
Table (3) Amount of Treated Sewage Waste Water
No.
Government
Quantity of water (000m3/day)
E.T. Losses 10% (000)/day
Quantity of treated waste water Discharged to Derange canals (000 m3/day (
1
Cairo
2582
258
2
Alex
1298
130
1168
3
Port Said
208
21
188
4
Suez
5
Dametta
195
20
176
6
Dakahlia
492
49
443
7
Sharkia
174
17
157
8
Qalubia
524
52
472
9
Kafr El-Shaikh
124
12
112
10
Gharbia
282
28
254
11
Monufia
149
15
134
Behera
25
229
13
Ismalia
219
22
197
14
Giza
1162
116
1046
Bani Suef
24
16
Fauom
115
103
Menia
82
74
18
Asut
60
54
19
Sohag
Qena
40
36
Aswan
67
Luxor
23
Red Sea
New Valley
27
Matruh
26
North Sinai
72
65
South Sinai
8456
844.4
7615
Source: Information Center and Decision Making Support, Prim Minister Cabinet, Cairo, Egypt, 2006.
Table (4) Economical Analysis of Jatropha Pilot Farm (000feddan).
Year
Seeds production (ton/fed.year)
Cultivated area (000 fed.)
Total Seeds production for a thousand feddan(ton)
Total production costs (L.E.)
Total revenue (L.E.)
Net income (L.E.)
per fed.
cultivated area(000)
cultivated area (000)
0.52
one
520
3659
3640
-19
0.63
630
4025
4410
385
2.08
2080
4427
14580
10153
2.6
4870
18200
13330
3.33
3330
5357
23315
17958
1.832
1832
4467.6
12829
8361.4
* Jatropha seed price per ton(L.E. 7000)
* Exchange rate $ one = 5.53 L.E.
Table (5): Oil Production of Jatropha Seeds on Five years(000 ton)
Oil production (ton/fed.)
Total Oil production (ton)
0.208
0.252
252
0.832
832
1.04
1040
1.332
1332
0.7328
732.8
* Jatropha Oil seed contain 40% Oil.
1Senior Researcher, Agricultural Engineering Research Institute, A.R.C., Egypt.
2Chairman, Joachim Kruger, Subterra Co, GMBH, Germany.
3Researcher, Agricultural Engineering Research Institute, A.R.C Egypt.
4Associate Professor, Economic Department, Faculty of Agriculture, Damanhour Branch Alexandria University, Egypt.
Abstract
Subterra Constructed Wetland is a natural system for wastewater treatment which employs the existing microorganisms and reed plants in sewage treatment. This paper presents the application of Subterra in LUXOR as a suitable solution for Nile cruise waste water treatment since it is easy to operate and maintain with reliable efficiency in BOD & COD reduction regardless of seasonal variations. LUXOR Station serve 1000 persons daily, also, Four Subterra station had been constructed at Agrotech farm in GIZA Governorate, Those stations serve about 700 persons daily, added to that post harvest facilities waste water. The effluent always has a better quality than required by usual legislation allowing its re-use in agricultural irrigation purposes. It has the advantage of using local resources for construction resulting in a more economic solution. The lifetime of Subterra stations extends to 40 years and only requires little sludge removal compared with other systems. The above mentioned stations are powered by electric motor pumps, each motor is One kWh, the actual total power consumed per day is 8 kW/h. The total amount of electricity consumed per 30 days is 240 kWh, the investment cost of Subterra station, indicated as follows:
Fixed cost: Materials: such as, Filter Excavation, Polyethylene liner, Derange pipes, Gravel, Sand, irrigation Pipes, Valves, Reed Plant, Design and construction supervision. Operation and Maintenance Cost: Labors, Electricity cost per month, Miscellaneous
Keywords: Constructed wetlands, Vertical flow lifts, Subterra system, Reed plant, Subsoil irrigation, BOD, and COD
Introduction:
This paper outlines the case study of applying a Subterra System in treating Nile Cruise waste water in Luxor, Egypt. The main aim of the project was to demonstrate natural waste water treatment efficiency and how it can be adapted to suit local conditions making use of local construction resources. The plan was to construct a sewage treatment plant with a capacity of 250 personal equivalence (p.e) and total daily waste water discharge of 40m3. This system allows the reuse of treated water in irrigation purposes at tourist installations. Another aim was to educate and inform the construction industry in Egypt and surrounding countries about natural treatment systems and their advantages including the protection of the environment as well as water saving.
Reclaiming municipal waste water for agriculture reuse is increasingly recognized as an essential management strategy in areas of the world where water is in short supply. Waste water reuse has two major objectives: it improves the environment because it reduces the amount of waste (treated or untreated) discharged into water courses, and it conserves water resources by lowering the demand for freshwater abstraction.
In the process, reuse has potential to reduce the cost of both waste water disposal and provision of irrigation water, mainly around cities and towns with sewers. In arid and semi-arid regions, the potential reuse of reclaimed waste water for irrigation is still limited. The reason for that could be the results of the following:
i) The unrestricted discharge of industrial waste into sewers making waste water unsuitable for irrigation.
ii) The problems arising from inadequate water resource and the inability to control such effluent quality, the site chosen for reuse and the methods of effluent application;
iii) Limitations imposed by climate and geography. Mediterranean Water Resources: Major Challenges Towards The 21stCentury ( Atef Hamdy March, 1999).
Counters utilizing waste water for agriculture, or planning the implementation of reuse system should consider the development of national standards and codes of practice for reuse, by adopting the WHO guidelines to their national priorities and taking into account their technical, economic, social, cultural and political characteristics and constraints ( Hespanhol and prost,1994).
On other hand, the use of raw of waste water for irrigation has been associated with the prevalence of many diseases such as ascariasas, typhoid fever and cholera, (Shuval et al., 1986).
The increase of productivity per unit area is not the only benefit since effluent irrigation can also provide an increase in agricultural production due to the growth in irrigated area and the possibility of multiple planting seasons (Bartone, 1986).
Arid and semi-arid countries are attempting more and more to integrate waste water in their national water policy and plans. The role of waste waters reuse in planning is discussed by Biswas,1986 (in: FAO, 1988). Translation of the national water policy and planning into operational and successful projects is the real challenge. Some changes in irrigation system, design and operation requirements have been reported by Pattygrove and Asano (1984) and Kay (1989).
Reed-bed purification systems are one of the oldest and most natural means of purifying sewage. In nature, water seeps into the soil, flows along roots, passes through natural filters of various sand- and gravel-layers and becomes purified through micro-organisms. Similarly, Subterra reed-bed purification systems use a combination of mechanical and biological mechanisms to treat waste water.
The paper starts with project information for Luxor Station followed by a general description of the Subterra system and its components. A highlight on operation & maintenance requirements is presented. Economics of the project are also discussed in order to demonstrate the cost efficiency of Subterra system.
The paper ends with discussion of results and conclusions.
Project information:
The Subterra reed bed purification system is a vertical filter system with a subterranean irrigation tube system. The treatment process starts with the mechanical treatment phase where the waste water goes into multi-chambered pretreatment pit. The size of the chambers depends on the size of the installation and quantity of sewage. Solid and light suspended materials are precipitated as a first step in those pretreatment chambers, which are treated at regular intervals. The second phase is the biological treatment, where the pre-treated sewage is pumped into the Subterra reed beds through special pressure piping system. The size of those beds is calculated on the basis of 50 to 150 liters water consumption per person per day. A special pressure piping system, Subterra pipes, which are embedded in the reed beds are used guaranteeing the even distribution of effluent over the highly effective filter of various micro-organisms as well as the aeration of the sewage through a spray-effect of those special perforated Subterra pipes. Here, the biological purification takes place.
The Subterra reed bed is lined with Polyethylene liner to protect the underlying soils and groundwater from any possible contamination. The bed consists of different layers of sand and gravel and is planted mainly with reed plants. The root system of the plants allows a constant aeration of the soil ensuring a continuous hydraulic flow on a long-term basis. The layer of micro-organisms formed on the roots allows nitrifiers and denitrifiers to break down organic compounds to such an extent that even benzyls and phenols are decomposed. Finally, the purified water is collected in a pipe and led to a control pit, where it can be examined and discharged into a pond, river or the ground through an irrigation network system. The treated waste water can also be used as recycled-water in households, in the same way as rainwater is used.
It is important to note the following:
Results and Discussion
Operation and Maintenance:
The Subterra station is easy to operate and maintain, requiring average skilled staff. The most common problems occurring during operation are pump failure or switch replacement. In few cases parts of the Subterra pipes require replacement due to burst or damage in one of the pipe as a result of mis-operation or high pressure pumping. However, even the pipe replacement follows a simple procedure.
The way Subterra beds are planned using multi control & distribution pits enable partial maintenance of the Subterra bed without the need of stopping the operation of the whole system.
Treatment Performance:
Subterra stations have been constructed since more 10 years in different parts of the world; Middle east, Europe, Asia and Africa. They have been performing with high efficiency even during extreme weather conditions. More than 220 stations have been installed with a varying capacity between 4 and 2500 personal equivalence for different purposes such as tourism developments, residential compounds, camping sites, Highway stops and gas stations.
The following table (1) and figure (5)indicatethe performance results of Luxor Station.
From the previous results it can be noticed the following was successfully achieved:
Economical Analysis:
The price of constructing a pilot Subterra station is highly affected by two items: Sand & Gravel. Once the sand & gravel are available in the area of the station, the costs are much reduced. In locations, where there is neither sand nor gravel available as natural resources and have to be procured from distant quarries, the cost of the station significantly increases.
In our case study, the construction cost for Luxor station amounted to 280 euro/p.e. However, this cost is a true reflection of the actual cost since Luxor station was carried out as a pilot project. For future stations the price should be half depending on the location of the station.
As for operation & maintenance cost they are extremely low due to the simple O&M process. For example, the energy consumption at Luxor station is approximately 4 kWh/d. Due to restricted Euro gap rules for export agriculture products from Egypt to Europe, the growers must meet this rules, one of this rules is environment protection such as, sewage waste water treatment. The growers intended to full file this rules, Agrotech Co farm cultivate fresh vegetables for export, the company farm employ about 700 persons daily. The company requested Subterra Co. to install four Subterra Sewage treatment station at the farm, to treat 20 cubic meter of sewage water daily for irrigation use.
The farm use to transport the Sewage waste water by trucks sewage tanks to a desert area and dump it, the quantity of Sewage waste water was transported to desert area 20 cubic Meter, the budget which was allocated yearly L.E.36500 for sewage transport, beside that, this amount of sewage water used to be discharged on desert surface area, and cause environment pollution. Meanwhile, the farm has to irrigate wood trees and landscape by fresh water, which is discharged from farm deep well, the cost of One cubic meter discharged from deep well is L.E.0.75 , therefore, the total cost of irrigation water per year is L.E.5400 . After, the farm had constructed Subterra system the farm saved under ground water, and reuse sewage treated water for tree woods and landscape irrigation. The total amount of saved money is L.E.41900 per year. Meanwhile, construction fixed cost is L.E.15635 and variable cost L.E. 4920, the total depression cost per year is L.E. 20554 in 20 years depression period, that means the farm saves 21421 L.E./year.
The economical and technical analysis indicated that, the station depreciation period of 40 years it is highly visible than 30 years and 20 years depreciation period. The economical calculation showed that, the cost of treating one cubic meter of sewage water by Subterra system is L.E 1.77 on 40 years depreciation period, L.E 2.13 on 30 years depreciation period, and L.E 2.85 on 20 years depreciation period.
Table (2) indicates the percentage of each item out of construction total costs.
Economical Use of Treated Sewage Waste Water:
Egypt has a need for a non-food crop, to absorb and recycled sewage waste water after treatment. Most of the sewage waste water stations were built at desert land, treated sewage water should be utilized on forest cultivation. Such as wood trees for furniture, paper pulp, oil trees for bio-fuel needs, trees to protect Egypt farm from desertification effect, and trees to increase green areas in order to increase oxygen and reduce atmospheric carbon dioxide level and thus global warming for environment protection, meanwhile, recycled treated waste water is important issue, to save water resources and reserve fresh water for other uses.
The aim of this research study, to highlight environmental services, recreation, quality of life and the benefit of sewage waste water recycled and conservation to irrigate wood lots (forest trees), such as Casuarina Glanca, Eucolyptus camaldulensis for woods production, and Jatropha trees for Bio-fuel production for sale on the local markets. (El-Lakany, 1995).
Amount of Treated Sewage Waste Water:
Table (3) shows that, the amount of treated sewage waste water in each Governorate daily on (2006). The daily amount equivalent to 8.456 million meter cubic/day, during the treatment stages, the average water losses is 844.4 thousands m3 /day.
Therefore, the remaining amount of treated sewage waste water is 7.615 million cubic meter per day, mostly discharged to drainage canals. According to, the amount of treated sewage waste water per day, Egypt could recycle about 3.139 billions m3 of treated sewage waste water per year in irrigation.
Economical Analysis of Jatropha Cultivation on One Thousand Feddan:
Table (4) stated that, the needs and benefit of forest cultivation could be irrigated by treated sewage waste water for sustainable environment. This table shows the assumption of a thousand faddan as a pilot, could be cultivated Jatropha trees for bio-fuel production, in order to reduce fossil oil use. Jatropha trees Oil seed production in five consecutive years is 0.52, 0.63, 2.08, 2.60 and 3.33 ton/fed, the average of five years production is 1.832 ton per fed. Oil seed. Production of One thousand fed. is 520, 630, 2080, 2600 and 3330 tons per year respectively. The production cost per fed., Include all agricultural practices, work for Jatopha cultivation and the installation of pressurized irrigation system is 3659, 4025, 4427, 4870 and 5357 L.E./fed. respectively , but the production costs for one thousand feddan for five consecutive years is 3659, 4025, 4427, 4870 and 5357 million L.E., Meanwhile, the revenue per fed. on five consecutive years is 3.640, 4.410, 14.580, 23.315 L.E per fed.., therefore, the revenue per thousand fed., on five consecutive years is 3.640, 4.410, 14.580, 23.315 million L.E., This pilot project of a thousand faddan after five years achieve net income is about L.E 8.361 million.
Estimated Oil Production of the Pilot Farm:
Jatropha Oil seeds content about 40% Oil, this Oil could be used as a Bio-fuel. Table (5) indicates the Oil production of a thousand faddan cultivated Jatropha trees. The average production of the suggested pilot farm on the first five consecutive year is 208, 252, 832, 1040 and 1332 tons respectively. The total average of Oil production is 733 ton/year. The production per faddan remains constant up to thirty years of trees life. Increasing Bio-fuel production from non-food crops in Egypt or in developing countries, this will reduce fossil Oil required. Meanwhile, this will encourage investors to establish forestry investment for Bio-fuel production. The biomass produced is used for construction, pulp and paper, fodder and energy. Wood from forestry may replace wood from tropical forests and from protected areas and thus help conserve valuable natural forests for future generations.
Conclusion
Over the years, Subterra has proved overwhelming efficiency and many benefits superior to other existing systems for sewage treatment. Through the demonstration of Luxor station as an example of applying Subterra station in Arab countries, the following advantages and benefits could be noted:
References:
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