Sustainable Management of Scarce

Resources in the Coastal Zone

SMART

ICA3 – 2001-1003

Kick-off Meeting

CEDARE, Cairo, 5-6 January, 2003

Case Study

Jordan

Introduction• Jordan has a surface area of (89.544) square kilometers with population of about (5) million

and rate growth of (3.4%).

• Jordan water resources are scare and are directly depending on the annual rainfall, which varies from year to year and also varies according to the locality from (50)mm in the eastern part to (600)mm in the northern and western mountains.

 • Jordan is characterized by a pronounced scarcity of renewable fresh water resources. It is

considered among few countries of the world with limited water resources. • Due to the population growth, the available renewable water resources per capita are falling

from around (188)m³/capita/year at present (2000) to (95)m³/cap/year by the year 2025. • The water resources of Jordan consist of surface and ground water resources and treated

wastewater used in irrigation. • Renewable water resources are estimated at about (940) MCM per annum, (280) MCM per

year ground water and (600) MCM per year surface water. An additional (143) MCM per year is expected to be available from fossil aquifers and about (75) MCM from brackish aquifers after desalination. Available treated wastewater from irrigation is about (70) MCM per year.

• Population growth, human settlement and socio-economic development will increase the demand on the limited water resources with priority in water allocation given to the domestic and industrial sector. Agriculture will suffer the most from water deficiency. One option to alleviate such suffering is to use non conventional resources like treated wastewater for irrigation.

 • Wastewater is essentially water that has been fouled by communities through its use in

the various daily activities such as cooking and washing. • Domestic sewage is mainly composed of human body wastes and sludge.  • Industrial sewage comprises numerous and various chemicals including those toxic to

humans and nature.  • Sewage is extremely hazardous in content mainly because of the number of disease

causing organism and toxic matter that it contains.

Wastewater Treatment.

• Treated wastewater generated at seventeen existing wastewater treatment plants is discharged into various water courses and flows to the Jordan Valley where it is reused for irrigation.

• About (73) MCM of treated wastewater are effectively discharged into the watercourses or are used directly in irrigation.

 

• Wastewater quantity is increasing with population growth, By the year 2020 when the population is projected to about (9.9) million and the percentage of sewage service to population increase from current (50%) to about (65%), about (265.3) MCM per year of wastewater are expected to be generated.

•Figure (1) shows the distribution of treatment plants in Jordan.

Table (1); Expected Treated wastewater Quantities WWTP Expected quantities in

MCM at Year 1996 2000 2010 2020

Reuse Site

As-Samra 46.3 55 110 174 King Talal dam, Zarqa River Basin, Around WWTP, As-Samra East, Al- Hashemiyah University

Aqaba 2.1 3 4 4.5 Around WWTP, Airport Highway Ramtha 0.5 0.7 1.9 2.5 Around WWTP Mafraq 0.7 1 1.3 1.7 Around WWTP Madaba 0.8 1.2 2.7 3.6 Around WWTP Ma’an 0.5 0.7 1 1.3 Around WWTP Irbid 2.8 1.6 4 4 Jordan River and Ghor in near future Jarash 0.6 0.6 1 1.3 Private farm Kufranjah 0.4 0.6 0.7 1 Around WWTP, Wadi Kufranjah Abu-Nusier 0.4 0.6 2 3 King Talal Reservoir Salt 1.3 1.2 3.5 5 Wadi Shuieb and shuieb Dam Baqa’a 2.4 3.65 5.4 7.3 King Talal Reservoir Karak 0.35 0.5 0.8 1 Wadi Karak Tafielah 0.3 0.4 0.7 1 Around WWTP and Wadi Tafielah Fuheis/Mahes - 0.4 0.7 1 Around WWTP Wadi Asir - 0.4 1.6 2 Around WWTP Wadi Hassan - - 0.6 0.6 Wadi Mousa - 0.5 1.25 1.8 Around WWTP Wadi Al-Arab 2.2 6 8.4 South Amman*

- - 12 1.8 Around WWTP

Nau’r* - 0.4 1.1 1.9 Kafrien Reservoir Ghor 1,2,3* - - 10.6 12.4 Ghor Site Wadi Al-Shallaleh*

- - 5 8 Ghor Site

* WWTP under study and construction

Table (1) shows the expected treated wastewater quantities till 2020

Advantage of Wastewater Reuse.• Treated wastewater is now being considered as new source of water that can be used

for different purposes such as agricultural and aquaculture production, industrial uses, recreational purposes and artificial recharge.

 • Using wastewater for agriculture production will help in alleviating food shortages

and reduce the gap between supply and demand. The interest in the reuse of treated effluent has accelerated significantly in the world since 1980 for many reasons;

1. Expansion of sewerage system networks and the increasing number of treatment plants.

2. Production of large quantities of wastewater which makes its use of agriculture viable alternative.

3. Wastewater is a rich source of nutrient and can reduce the use of fertilizers.4. The reuse is a safe disposal of wastewater which will reduce the environment and

health risks.5. The treatment of wastewater to be used for irrigation is cheaper than that needed for

production of the environment. Regulation to discharge water into sea and streams or groundwater recharge are more strict than reuse for irrigation.

Development of Sanitation Services.• Until 1969, cesspools, septic tanks and other on-site methods were used for the disposal of wastewater. • This practice coupled with rapid and uncontrolled population growth resulted in major environmental

problems especially surface and groundwater pollution.

• The government of Jordan has realized the magnitude of the problem and the necessity to build a safe disposal system for wastewater.

 • In 1969, the municipality of Amman completed a sanitary sewage system to serve the population of

Amman with (500,000) people. This system was associated with a conventional activated sludge plant with a capacity of (60,000) m³/day and a BOD loading of (18,000) kg/d. The design effluent standard BOD was (20)mg/L and the effluent was discharged to the Zerqa river a major tributary of the Jordan river.

 • Due to the high strength of raw sewage (BOD5> 600 mg/L), the effectiveness of the plant was drastically

reduced to the extent that the actual capacity became only (30,000) m³/d by the year 1980. The operation under high hydraulic and organic loading conditions resulted in an effluent that could not meet the standard of (BOD5<20mg/L) and low efficiency in the process of solid processing and disposal. As such, the quality of surface and groundwater was deteriorated due to the use of low quality water for irrigation downstream.

• In the 1980s, the government built a major wastewater stabilization pond (WSP) system for the Greater Amman Area and other treatment facilities in major cities and towns in the country totaling (17) treatment plants.

 • By the year 1999, about (50%) of the plants were overloaded including the largest WSP of Amman. The

government has completed a master plan study to upgrade and expand existing facilities and to build new plants in the country aiming at (90%) coverage of the population by the year 2010.

 • In Jordan a diverse range of wastewater treatment plants are used in various cities ranging from

conventional treatment methods and wastewater stabilization ponds in large communities to simple treatment technologies in small communities.

 The mostly used conventional methods are:1. Stabilization Ponds: This technology is used in the waste treatment plant of As-Samra, Mafraq,

Ramtha, Ma`an, Madaba and Aqaba.2. Activated Sludge: It is used in the treatment plants of Irbid, Salt, Jarash, Tafilah, Fuhis and Baqa`a.3. Trickling Filters: Used in the wastewater treatment plants of Karak, Kufranja, West Irbid and Abu

Nusair.4. Aerated Lagoons: Used only in Wadi Essir wastewater treatment plant. 

MONTHWWTP

 

JanM3/day

Feb.M3/day

Mar.M3/day

Apr.M3/day

MayM3/day

JuneM3/day

JulyM3/day

Aug.M3/day

Sept.M3/day

Oct.M3/day

Nov.M3/day

Dec.M3/day

Avg.M3/day

TotalMCM/Year

AS-SAMRA W.S.P 153386 154327 151018 147713 146863 148901 132215 126702 138555 151970 145751 1155651 146088.1 53.322

AQABA W.S.P 7037 6893 7234 8406 7558 7291 6748 6982 7570 7666 6989 6800 7272.8 2.655

RAMTHA W.S.P 1643 2099 2597 1676 1814 1768 2003 1607 1941 1936 1700 2024 1892.8 0.691

MAFRAQ W.S.P 1215 1380 1460 1562 1432 1520 1200 1250 1300 1120 1580 1620 1386.6 0.506

MADABA W.S.P 3274 3610 4100 2903 4413 4280 3210 4290 3373 3194 3937 3939 3702.8 1.362

MA’AN W.S.P 1444 1298 1751 1725 1621 1457 1524 906 1296 1988 1800 1490 1524.9 0.557

IRBID 4646 4484 5268 4524 4642 4996 5141 5170 4947 4771 5667 9013 4939.0 1.8.3

JERASH 2738 2779 2631 2577 2745 2649 2549 2543 2659 2545 2765 3135 2692.9 0.983

KUFRANJA 1771 1982 1736 1320 1458 1184 906 1418 1408 1320 1933 2811 1603.9 0.565

ABU-NUSIER 1731 1768 1695 1650 1690 1655 1835 1760 1810 1717 1818 1914 1746.9 0.638

SALT 2710 3022 3500 3661 3400 3730 3988 4000 3988 3666 3910 3100 3556.3 1.298

BAQA’ 11209 11639 11167 10547 10531 10625 10766 10795 10730 10952 11004 11318 10940.3 3.993

KARAK 1200 1100 1100 1225 1226 1260 1255 1265 1300 1266 1300 1260 1229.8 0.449

TAFILA 793 814 768 694 684 679 680 726 723 766 778 802 742.3 0.271

WADI AL SEER 1232 1229 1064 862 992 1080 1507 1419 1060 1179 1448 1577 1220.7 0.446

FUHIS 1258 1143 1000 1036 1097 950 968 950 1000 933 1100 1100 1044.6 0.381

WADI ARAB 4892 4539 4510 4768 4608 4352 5651 5990 5775 5900 4120 4178 4906.9 1.791

WADI HASSAN                 0 0 0 0 0 0.000

WADI MOUSA     0 0 0 0 0 236 598 699 501 566 260.0 0.040

TOTAL M3/D 202184 204105 202599 196849 196689 198387 182146 177519 190033 203488 196101 208398 196708.0 71.8

TOTAL M.C.M(PER MONTH)

6.2677 5.7149 6.2806 5.9055 6.0974 5.9516 5.6465 5.5031 5.7010 6.3081 5.9430 6.4603 6.0 71.8

Table (2a): Wastewater treatment Plants, Daily Average Effluent, 2001

Table (2a) shows the wastewater treatment plants, daily average effluent (2001) and Table (2b) shows the treatment method, design parameters, average daily influent and the organic and solids concentration (1999) of the (17) major wastewater treatment plants.

Design Parameters Influent characteristics

BOD5 mg/l

TSS mg/l

Plant Treatment Method Flow rate (m3/d)

Influent Effluent Influent Effluent

Flow rate (m3/d)

BOD5 mg/l

TSS mg/l

As-Samra Stabilization Pond 68000 526 30 550 50 166844 760 545 Aqaba Stabilization Pond 9000 900 50 400 50 8774 353 266

Ramtha Stabilization Pond 1920 820 50 850 50 2174 1194 964 Mafraq Stabilization Pond 1800 825 50 850 50 1933 566 249

Madaba Stabilization Pond 2000 850 50 850 50 3609 1332 1657 Ma’an Stabilization Pond 1600 970 50 1000 50 1738 549 715

Irbid Activated Sludge and T.F. 11000 800 30 800 50 4612 1179 1139 Jarash Activated Sludge 3500 119 33 943 68 1603 1119 943

Kufranjah Trickling Filters 1900 850 30 850 30 1734 1331 1023 Abu-Nusear Activated Sludge and R.B.C. 4000 1100 30 1000 30 1411 634 601

Salt Activated Sludge 7700 1090 30 1000 30 3166 845 828 Baqa’a Trickling Filters 6000 900 30 900 30 10284 1434 1720 Karak Trickling Filters 785 1080 30 1000 30 1146 729 697

Tafilah Activated Sludge 1600 1050 30 1000 30 851 942 700 Wadi Al-sear Aerated Lagoon 4000 780 30 850 30 914 622 565

Fuheis Activated Sludge 2400 995 30 850 30 1019 677 720 Wadi Arab Activated Sludge 22000 995 30 850 30 5993 811 1269

Table( 2b); Treatment methods, total influent , design parameters of wastewater treatment plants in Jordan(1999)

Cost of Treatment.

Items WWTT

Salary JD

Elect. JD

Water JD

Spare Parts

JD

Chemicals &

Chlorine JD

Sludge Disposal

JD

Fuel & Oil JD

Pesticide JD

Others JD

Total Cost JD

Annual Influent M³/year

Cost of Treatment

Files/m³

As-Samra WSP 116000 420000 7000 10000 5000 0 7500 10000 54120 629620 60698060 10.37 E.Zarqa P.ST 22000 50000 1000 30000 250 1000 1000 250 2000 107500 3866587 27.80 W.Zarqa P.ST 54000 204000 11400 160000 0 5000 12000 250 1700 448350 14346000 31.25 �ِAin.Ghazal 66720 4100 3000 550 600 160 0 1870 77000 42482879 1.81

Total 258720 678100 19400 203000 5800 6600 20660 10500 59690 1262470 60698060 20.80 Aqaba WSP 33000 9500 1500 1000 0 0 600 4000 1300 50900 3202510 15.89 Aqaba P.ST 24000 18000 3000 15000 2000 0 600 200 800 63600 2802427 22.69 Total 114500 3202510 35.75 Madaba WSP 33898 8174 377 3500 420 110 2475 1385 3453 56792 1317285 43.11 Irbid 113000 37500 1000 4790 12000 23700 5000 1000 4400 202390 1683380 120.23 Salt 38000 71203 400 17800 5100 14500 1100 500 1800 150403 1155590 130.15 Jerash 49000 23557 500 7500 3537 2596 740 300 1100 88830 623436 142.48 Mafraq 51328 7518 600 8000 250 0 250 250 200 68396 705545 96.94 Baqa’a 77000 60000 500 18500 5000 42000 10000 2000 5250 220250 3753660 58.68 Ain Basha 20000 6000 150 3000 0 0 900 500 150 30700 412021 74.51 Total 97000 6600 650 21500 5000 42000 10900 2500 5400 250950 3753660 66.85 Karak 45000 2237 100 4000 9400 250 2450 300 3842 67579 418290 161.56 Abu-Nuseir 49320 26890 385 600 2340 4520 1067 0 1265 86387 515015 167.74 Tafila 48678 9124 743 5000 120 0 1175 130 9398 74368 310615 239.42 Ramtha 26896 6587 220 8000 0 0 3132 75 1755 46665 793510 58.81 Ma’an 37 1080 200 5630 0 0 1430 480 145 46350 634370 73.06 Kufranja 51320 13200 120 10430 0 0 3200 1100 3480 82850 632910 130.90 Wadi Essir 53242 10769 110 1380 1386 0 2915 1340 1185 72327 333610 216.80 Fuhais 54000 20000 150 1000 2400 2200 2000 160 200 82110 371935 220.76 Fuhais P.ST 15000 1800 150 700 0 0 50 75 400 18175 82632 219.95 Total 100285 371935 269.63 Wadi Arab 89600 78800 1600 0 5400 12000 2968 9200 202736 1468285 138.08

Table(3); Wastewater Treatment Plants Cost of Treatment (Fils/m³) (1999)

Table (3) shows the total cost of wastewater treatment in different wastewater treatment plants in Jordan, the cost includes depreciation cost, salary, electricity, operation and maintenance, chemicals, sludge disposal, contracted testing, and others.

The cost of treated unit volume of effluent ranges from (0.01) JD/m³ in large stabilization pond of As-Samra to (0.24) JD/m³ in small activated sludge plant of Tafilah

Wastewater Reuse In Agriculture.• Historically, the concept of using sewage effluents for irrigation can be traced back to more than

2000 years ago.  • When crops in Greece were irrigated with such effluent • the practice has been prevalent in china for centuries. • In Europe, farming with sewage was common practice in Germany as early as the sixteenth

century. • The first recorded use of sewage effluent for agriculture in the USA appears to have been in the

late 1870s.  • In Jordan the indirect reuse of wastewater effluent has been practiced for a number of years, as

it has been discharged into the main wadis and mixed with the surface flow. Farmers along the banks of these wadis used to pump water or direct the flow of the wadis and reuse it for unrestricted irrigation. Natural recharge to aquifers takes place through wadis beds.

 

• In Jordan the direct and controlled reuse of treated effluent has been increasing since 1985.

• At the national level, the total production of the treated wastewater is about (73) MCM as of 1999. Nearly all these amounts are being reused mainly for agriculture (95%), about (3%) for groundwater recharge and (2%) for industrial uses.

• This practice is a result of the government policy so as to conserve water as a scarce and valuable resource.

 

• The government of Jordan has introduced new legislation on effluent quality to control its use considering public health issues and protection of the environment.

 

• It is mandatory that all treatment plant projects must include a fully designed and feasible reuse scheme.

Below is a brief description of reuse schemes that are currently in operation. Zarqa River Basin Scheme

• Is the largest reuse system in operation in Jordan. • There are four treatment plants located in the basin that discharge its treated effluent to Zarqa River

where it is collected downstream at King Talal Dam and used for restricted irrigation in the southern section of the Jordan Valley.

 • The largest treatment plant is As-Samra waste stabilization pond treating about (60) MCM where most of

it joins the flow of Zarqa River. A small portion (2%) of this effluent is used for on-site irrigation of about (300) hectares planted with olive trees, fodder crops and forest trees.

 • The other plants (Jarash, Abu Nusair, and Baqa’a) discharge about (4.0) MCM to the same river. • King Talal Reservoir with a capacity of (85) MCM collects surface runoff and treated sewage effluent

which results in quality variation from summer to winter. The total irrigated area by the reservoir water release is about (10,000) hectares.

 

AqabaWSP• The volume of domestic treated wastewater from Aqaba WSP reached (3.2)

MCM in 1999. About (1.5) MCM is used for irrigating palm trees and the rest is used for artificial recharge using infiltration basins.

Ramtha, Ma’an, and Madaba WSP• These three plants are served with three WSP producing about (3.5) MCM

(1999) where it is used for irrigating fodder crops and trees around the WWTP.

Salt, Tafielah, Karak, Irbid and Kufranja • These plants are treated about (6) MCM. Where their effluents join the stream

of wadis. This water is also used by downstream users for irrigation or collected in small dams, which are built on the wadis for later use in irrigation.

Table (4); Direct Reuse Area in Jordan

Planted area (ha)

Crop's Excess Effluent

Flow As-Samra 300 Olive, forest, fodder King Talal Dam Aqaba 150 Forest, some olive trees None

Ramtha 50 Forest, barely, sudan grass, alfalfa

None

Mafraq 25 Forest, fodder crop None

Madaba 60 Forest, olive, fodder, flowers

None

Ma’an 7 Forest, olive, ornamental trees

None

Irbid 0.5 Forest, ornamental trees Jordan River Jarash - - KTD

Kufranja 7 Forest, olive, sudan grass, alfalfa.

Wadi Kufranja

Abu-Nusair 0.5 Forest, olive. KTD Salt - - Wadi Shuieb Baqa'a - - KTD Karak 3.5 Olive, ornamental trees Wadi Karak Tafielah 1 Olive, fruit trees Ghor Fifa Fuhais/Mahas 24 Forest, fruit trees None Wadi Essir 15 Forest, fruit trees None Wadi Al- Arab - - Jordan River

Wadi Musa - None

Wadi Hassan None

South Amman

Nau'r

Ghor 1,2,3

Wastewater treatment plants under study and construction

Table (4) shows direct reuse areas and crop patterns in Jordan.

•There are about 6 small domestic treatment plants serving the residential areas of the employees of major industries (Cement, Phosphate, and Potash) providing about (1.5) MCM of water. Some of this water is used for on-site irrigation and the rest is reused in industries for cooling purposes.

•Industrial water from the two major industrial cities (Sahab and Al Hassan) is treated separately and is used for on-site irrigation.  •Scattered industries, whose influent could not join the domestic wastewater, are using their industrial effluent for on-site irrigation like the yeast and paper factories.  •The effluent of hazardous industries like paint, batteries, chemicals and pharmaceutical are disposed through evaporation or incineration.  •Phosphate mining and processing is considered one of the main industries in Jordan, which consumes about (20) MCM of water. Recently, the processed water has been recycled after settling and filtration.  • The effluent of the treatment plants of Amman Airport and Al-Hussein Medical City are used for irrigation of grasses, green areas and forest trees in the vicinity of the two sites.

Regulations and Legislations.

• Concerned agencies have issued regulations and standards that are used to implement their wastewater management policies.

 • These regulation cover agencies in charge of, collection of sewage, treatment process and disposal and

discharge. • The discharge of industrial and commercial wastewater into the sewerage system is strictly prohibited

unless such effluent comply with standards of domestic wastewater. • If these regulation are violated, the concerned agencies have the full right to take immediate actions

including imposing penalties. • All house owners or leaseholders residing in an estate, which is served by a sewerage system network, are

encouraged to connect. • The discharge of surface runoff water or storm water into the sewerage system networks is strictly

prohibited. • Sometimes, tertiary treatment of wastewater including ozonation or chlorination is needed before the

effluent is discharged.

• Lately, regulations and guidelines to direct the reuse of reclaimed water have been given the necessary importance with regard to the associated health and environmental impact. In 1982 and after thirteen years of uncontrolled use, Jordan issued standards through a by-law, which allows irrigation by wastewater only for trees and fodder crops. Jordanian standards and regulations were updated in 1995 with the following general criteria:

1. The treated wastewater must meet the specified standards that vary according to the planned use.2. When treated effluent is used for irrigation of fruit trees, cooked vegetables and fodder crops, irrigation must

be ceased two weeks before collecting the products. Fallen fruit should be discarded.3. The adverse effect of certain effluent quality parameters on the soil characteristics and on certain crops should

be considered.4. Use of sprinkler systems for irrigation is prohibited.5. Use of treated effluent in the irrigation of crops that can be eaten raw such as tomatoes, cucumber, carrots,

lettuce, radish, mint, or parsley is prohibited.6. Closed conduits or lined channels must be used for transmission of treated effluent in areas where the

permeability is high, which can affect underground and surface water that could be used for potable purposes.7. Dilution of treated water effluent by mixing at the treatment site with clean water in order to achieve the

requirements of this standard is prohibited.8. Use of treated effluent to recharge an aquifer, which is used for potable water supply purposes, is prohibited.

• Tables (5&6) presents the Jordanian standards for wastewater discharge and reuse (893/95).

 

• The major features of these tables are not to permit application of treated sewage water in irrigation of fresh vegetables.  

 

• In addition, restriction on the utilization of treated wastewater increases with switching the destiny of grown plants from animal to human food.

Table 13: Maximum Concentration of Reclamied water Targete for Reuse in Agriculture according to Joradn Standards

Quality Parameter mg/L

Vegetables eaten Cook

ed

Fruit Trees Cereal Crops

Discharge to

Streams and

Water Body

Artifical Groundwater Recharge

Fish and Aquacultur

e

Puplic

Parks

Fodder and

Pastures

BOD5 150 150 50 50 - 50 250 COD 500 500 200 200 - 200 700 DO >2 >2 >2 >2 <5 >2 >1 TDS 2000 2000 2000 2000 2000 2000 2000 TSS 200 200 50 50 25 50 250

PH 6.0-9.0

6.0-9.0 6.0-9.0 6.0-9.0 6.0-9.0 6.0-9.0

6.0-9.0

Color (PCU)

- - 75 75 - 75 -

FOG 8 8 8 N.D 8 8 12 Phenol 0.002 0.002 0.002 0.002 0.001 0.002 0.002 MBAS 50 50 25 15 0.2 15 50 NO3-N 50 50 25 25 - 25 50 NH4-N - - 15 15 0.5 50 -

T-N 100 100 50 50 - 100 - PO4-p - - 15 15 - 15 -

Cl 350 350 350 350 - 350 350 SO4 1000 1000 1000 1000 - 1000 1000 CO3 6 6 6 6 - 6 6

HCO3 520 520 520 520 - 520 520 Na 230 230 230 230 - 230 230 Mg 60 60 60 60 - 60 60 Ca 400 400 400 400 - 400 400

SAR 9 9 9 9 - 12 9 Al 5 5 5 1 - 5 5 As 0.1 0.1 0.05 0.05 0.05 0.1 0.1 Be 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Cu 0.2 0.2 0.2 0.2 0.04 0.2 0.2 F 1.0 1.0 1.0 1.0 1.5 1.0 1.0 Fe 5.0 5.0 2.0 1.0 0.5 5.0 5.0 Li 2.5 5.0 0.1 0.1 - 3.0 5.0

Mn 0.2 0.2 0.2 0.2 1.0 0.2 0.2 Ni 0.2 0.2 0.2 0.2 0.4 0.2 0.2 Pb 5.0 5.0 0.1 0.1 0.15 0.1 5.0 Se 0.02 0.02 0.02 0.02 0.05 0.02 0.02 Cd 0.01 0.01 0.01 0.01 0.015 0.01 0.01 Zn 2.0 2.0 15 15 0.6 2.0 2.0 Cn 0.1 0.1 0.1 0.1 0.0005 0.1 0.1 Cr 0.1 0.1 0.05 0.05 0.1 0.1 0.1

Category Reuse condition

Exposed group

Intestinal nematodes b (arithmetic mean no. of eggs per liter c )

Fecal coliform (geometric mean no. per 100 ml c )

Wastewater treatment expected to achieve the required microbiological quality

A Irrigation of crops likely to be eaten uncooked, sports fields, public parks d

Workers consumers public

1 1000 d A series of stabilization ponds designed to achieve the microbiological quality indicated, or equivalent treatment.

B Irrigation of cereal crops, industrial, crops, fodder crops, pasture and trees e

Workers 1 No standard recommended

Retention in stabilization ponds for 8-10 days or equivalent helminthes and fecal coliform removal

C Localized irrigation of crops in category B if exposure of workers and the public does not occur

None Not applicable Not applicable Pretreatment as required by the irrigation technology, but not less than primary sedimentation

Table 14: Recommended microbiological quality guidelines for wastewater use in agriculture

a)        In specific cases, local epidemiological, socio cultural and environmental factors should be taken into account, and the guidelines modified accordingly.

b)       Ascars and Trichuris species and hookworms.

c)        During the irrigation period.

d)       A more stringent guideline (<200 fecal coliform per 100 ml) is appropriate for public lawns, such as hotel lawns, with which the public may come into direct contact.

e)        In the case of fruit trees, irrigation should cease two weeks before fruit is picked, and no fruit should be picked of the ground. Sprinkler irrigation should not be used.

Source: WHO, 1989.

Government Policy On June, 1998 the government established the latest policy for wastewater

management and reuse, it’s main features on reuse of treated effluent is as follows:• Treated wastewater effluent is considered a water resource and is added to the water

stock for reuse. This warranted and deemed feasible in light of the semi arid climate, the modest per capita share of freshwater resources, the high demand for municipal water, the per capita share of the deficit in the trade of food commodities, and of the marginal cost of resource development.

• Priority shall be given to agricultural reuse of treated effluent for unresticted irrigation. Blending of treated wastewater with fresh water shall be made to improve quality where possible. Crops to be irrigated by the treated effluent of blend thereof with freshwater resources shall be selected to suit the irrigation water, soil type and chemisty, and the economics of the reuse operations.

• Crop nutrients requirement shall be determined taking into consideration the prevailing effluent quality. Overuse of nutrients shall be avoided.

Government Policy continued

• Accumulation of heavy metals and salinity shall be monitored, managed and mitigated.

• Farmers shall be encouraged to determine the rate of water application needed for different crops, taking into consideration the value of nutrients in the treated water and other parameters.

• Farmers shall be encouraged to use modern and efficient irrigation technologies. Protection of on farm workers and of crops against pollution with wastewater shall be ensured.

• Treated effluent quality should be monitored and users be alerted to any emergency causing deterioration of the quality so that they will not use such water unless corrective measures are taken.

• Studies should be conducted and projects designed and implemented to store the excess treated wastewater in surface reservoirs or in groundwater reservoirs through artificial recharge technique.