SEWAGE EFFLUENT DISCHARGE REGULATIONS FOR IRRIGATION DEVELOPMENT IN THE MIDDLE EAST REGION

 

T. Sammis[1], B. Stewart[2], W. Zachritz[3]

 

ABSTRACT

Water shortages have plagued the Middle East region since early civilizations. Today, water continues to be overexploited. The water resource problem remains one of the most complex and urgent of any region in the world.

The agriculture sector is the major consumer of water in the Middle East region, utilizing in some countries up to 80 percent of available water. As water demand increases in the region, with decreasing supplies, the efficient use of water will need to be improved in all sectors. Agriculture will face increased economic pressure from municipal and industrial users.

Treated sewage wastewater is an alternative water source for agriculture. Because water “knows no political boundaries,” pollution control methods and degree of treatment in one country will affect the management of water resources in another country. Therefore, the use of wastewater in agriculture will need similar standards throughout the region.

Currently, each country has a unique system of rules and regulations to protect the quality of their water resources. To improve and coordinate the waste water treatment policies of each country it is essential to understand the similarities and differences in water regulatory systems.

This paper describes an Internet site that presents information on the current water quality laws, regulations and application standards for discharge of wastewater into rivers, lakes and irrigation systems in Egypt, Israel, Jordan and the Palestinian Authority.

It is hoped that policy makers and extension agents will use the Internet site to compare their system of regulations with those of their neighbors and to make changes based on knowledge gained from such comparisons.


KEYWORDS: Sewage disposal, Wastewater, Internet, Agriculture.


INTRODUCTION

 

Water has been a scarce resource in the Middle East since early civilizations. Water resource allocation continues to be the most urgent and pressing issue for the region. Today, water shortage in the Middle East has forced countries to reuse treated wastewater for agriculture, industry, recreation and to recharge aquifers (Asano & Mills, 1990). ). The primary problem associated with using treated wastewater for agriculture is the inherent health risks from wastewater containing bacteria, viruses, and a wide range of parasitic organisms.  Generally, indicator organisms are used to reflect the sanitary quality and suitability of particular water reuse or consumption.  Typical indicators are fecal coliform content measured as CFU/100mL (colony forming units) and the number of helminth eggs or ova (Ascaris and Trichuris species and hookworms) in a water sample.

Waste water can also contains large amounts of dissolved and suspended organic matter that has the potential to clog soil pores and irrigation equipment emitters. Clogged soils have a decrease in permeability resulting in poor irrigation efficiencies and water logging due to poor drainage. Irrigation emitters of various types (drip, microsprayers, etc) can become clogged by particulate matter and the development of biogrowth or biofouling.  Wastewater effluent applied through a drip irrigation system typically requires sand filtration as a pretreatment to avoid problems with clogging. The organic content of the wastewater is expressed as Total Suspended Solids (TSS) and as Biochemical Oxygen Demand (BOD) both reported as mg/L.

In agriculture, treated wastewater has been applied mainly to field crop but Gideon Oron et al. (1999) demonstrated that sweet corn (zea maize), Saccharatum and sweet pepper (paprika) could be irrigated using treated wastewater through subsurface drip irrigation systems without detection of fecal coliform in plant parts and with minimal bacteria concentrations in the soil surface. Maximum bacterial concentrations was detected at a soil depth of 30-50 cm. Oron’s study supports previous work by Gerba (1975).

Wastewater reuse rules for agricultural lands in the Middle East countries either follow the rules developed by the World Health Organization (WHO, 1989) or they follow more stringent rules developed in the United States by the State of California. In the Middle East, federal agencies are in charge of wastewater management (Table 1).

Table 1.  Federal Agency in Middle East Countries responsible for wastewater regulations.

Country

Federal Agency

Jurisdiction

Jordan

Ministry of Water and Irrigation

Regulates and manages both the drinking and wastewater treatment plants

Regulates the crop and conditions under which wastewater can be used in agriculture

Palestinian Authority

Ministry of Environmental Affairs

Wastewater management

Israel

Ministry of Health (Jerusalem, the Chief Health Engineer)

Wastewater management

Egypt

Ministry of Agriculture

Regulates the application of wastewater

The standards were developed to protect health of the agricultural workers, those who might enter a field in which wastewater is used as irrigation water, and the general public. The standards either specify a microbiologic quality guideline or a method of wastewater treatment that will achieve the required microbiological quality.

WHO standards for the use of wastewater in agricultural production for export generally require a level of treatment that ensures that the fecal coliform content of the wastewater is less than 103 cfu per 100 ml (WHO, 1989). WHO also sets standards for helminth eggs and intestinal nematodes that may be a problem for agricultural workers, consumers, and the public when the wastewater is surface applied or flood irrigated. The wastewater effluent should contain less than 1 heliminth egg per liter. The WHO recommended treatment methodology to achieve this standard is a series of stabilization ponds (aerobic, facultative, and polishing lagoons) with a hydraulic retention time (HRT) of not less than 8-10 days. This health problem only exists where intestinal nematodes are prevalent. These standards do not address the risks if the wastewater is applied through a subsurface drip irrigation system.

WHO standards do not take into consideration the technology for application of wastewater that may help reduce health risks. If subsurface drip irrigation is used to apply the irrigation water, the health risks are negligible (Oron et al., 1999). When using subsurface drip irrigation, the treatment of wastewaters to levels less strict than that generally required by WHO may, in fact, still produce food products that are completely safe for human consumption and export. Therefore, it is important to investigate the use of subsurface drip irrigation as an alternative to surface irrigation and as a preferred method of application of wastewater.

Currently in the Middle East, wastewater treatment levels for application to agricultural land range from zero—discharge of raw sewage—to highly treated water produced from newly constructed wastewater treatment plants. Trained operators who carefully monitor the wastewater stream for health risk levels run these plants. The long-term goal of all Middle East countries is to treat wastewater used in agriculture to minimum WHO standards. The minimum levels defined by WHO as acceptable, however, they might be made less strict  if the products remain safe and meet required standards when using subsurface drip methods for applying the water. The biggest problem facing policy makers and end users of treated wastewater in agriculture production is a lack of understanding of the standards, acceptable levels of treatment, methods of application and the maintenance of wastewater treatment systems.

Understanding all of the issues and problems associated with the use of treated wastewater in agriculture is a global concern. There is no central data bank for reference. However, there are several groups that have been formed to research and compile information on the topic.

In the United States, the Consortium of Institutes for Decentralized Wastewater Treatment was established with the purpose of compiling information and promoting standardized education and training of new approaches and tools for wastewater treatment. The consortium is made up of representatives from educational institutions, special interest groups, regulatory agencies and private industry. The Internet web site is used as the method of disseminating information about wastewater treatment and application (CIDWT, 2000), http://www.dal.ca/~cwrs/cdwt/.

The National Small Flows Clearinghouse (NSFC, 2000) is another web-based site that maintains several databases on regulations, technologies, and people who have experience in small wastewater treatment systems. The purpose of the clearinghouse is to provide information on wastewater issues to homeowners, government officials, operators, manufacturers, contractors, and related professionals, http://www.estd.wvu.edu/nsfc/NSFC_homepage.html.

In the Middle East an Appropriate Technology Consortium (ATC) was formed to develop low-cost, efficient, and replicable wastewater treatment and reuse systems in rural areas of the Middle East. The consortium consists of the following Institutions: The Galilee Society (Israel), The Palestinian Hydrology Group (West Bank), The Egyptian Center of Organic Agriculture (Egypt), The Technion, Israel Institute of Technology (Israel) (ATC, 2000).

Each country in the Middle East has a unique system of rules and regulations to protect the quality of their water resources and to regulate wastewater use and application. Each country system has some similarities to its neighbors’ system but also some differences. To improve and coordinate the clean water policies of each country it is essential to understand the similarities and differences in water regulatory systems and wastewater use and application.

PURPOSE

This paper describes an Internet site that presents information on the current water quality laws, regulations and application standards for discharge of wastewater into rivers, lakes and irrigation systems in Egypt, Israel, Jordan and the Palestinian Authority. The similarities and differences in the laws and regulations of each country are presented.

It is hoped that policy makers and extension agents will use the Internet site to compare their system of regulations with those of their neighbors and to make changes based on knowledge gained from such comparisons.

MATERIALS AND METHODS

Information on the regulations of the use of wastewater for the Middle East countries of Israel, Palestinian Authority, Jordan, and Egypt were acquired by contacting the ministry in charge of wastewater use in their respective countries. A search of databases on the Internet was used to identify projects using wastewater for agriculture in the Middle East.

The site (Fig. 1) was initially established at New Mexico State University for development purposes (MEWUC, 2000) but will be moved to the San Diego State University site upon completion.

Figure 1. Middle East Wastewater Use Clearinghouse Internet Site.

 

RESULTS AND DISCUSSION

 

The development of a web-based information system on wastewater has been undertaken by many organizations and these sites, including the one at New Mexico State University, offer a cost-effective method of disseminating information to interested parties. For those parties that do not have easily accessible Internet connections, the entire Internet site can be installed on a compact disk (CD) and read with an Internet browser.

The amount of information on the Internet on regulations and methods of application of wastewater to agriculture lands depends on the availability of resources to compile and create Internet information. In the Middle East, Israel and the Palestinian Authority already are using the Internet for disseminating this information.

The World Health Organization (Table 2) set the standards for wastewater use in agriculture. Jordan and the Palestinian Authority are using these by default.  Actually, the Palestinians have not formally adopted the WHO standards but they are in the process of developing their own standards based on the WHO formula.

Table 2. The World Health Organization's criteria for effluent application for irrigation agricultural crops.

Constituents
(Mg/1)

Group A
Irrigation of crops to be eaten uncooked

Group B
Cereal crops, industrial crops, fodder crops, pasture and trees

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

Effluent quality

 

 

 

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

<1

<1

N/A

Coliform Counts/100 ml

<1000

No Standard

N/A

Mandatory treatment

 

 

 

Stabilization pond

Required

Required
8-10 days retention time

N/R

Equivalent water treatment plant

Required

N/R

N/R
Pretreatment needed by irrigation technology or primary sedimentation

*N/R means not recommended

The WHO (1989) states that wastewater can be applied to the land using flood irrigation but this method of irrigation should not be used for producing vegetables. Flood irrigation probably exposes field workers to the greatest health risk. WHO also states that sprinkler irrigation should not be used on vegetables and fruit unless the effluent meets the guideline for “Group A” conditions. Subsurface or localized irrigation, with the surface covered with plastic mulch, gives the greatest degree of health protection when using treated wastewater. Because the WHO is concerned only with the health risk of using wastewater, the organization does not set other water quality standards that Israel requires for the application of treated wastewater to agricultural lands (see Table 3).

Israel is concerned with the health risks and also the BOD content of the wastewater. The BOD levels are important because if the level is too high the solid matter can plug the irrigation emitters when using a drip system if the water is not properly filtered. Egypt applies even more stringent regulations for the use of wastewater. Egypt prohibits its use on any food or fiber crop including cotton. Currently, wastewater can be applied to trees and landscape only.

Problems associated with using treated wastewater through a drip system depend on the level of treatment. The worst-case situation is when the wastewater receives only primary treatment. This condition exists in the United States where private homes discharge the wastewater from septic tanks through a subsurface drip irrigation system instead of a leach line. Experience has shown that with proper filtration and an automated flushing system for the filter, the drip system with regular maintenance can apply wastewater to lawns without problems. However, the drip tubing has to be designed specifically for wastewater (Lesikar, 2000).

Table 3. Israel's criteria for effluent application for agricultural irrigation (1).

Constituents
(mg/1)

Group A
Cotton, sugar beet
plants for seeds
production

Group B
Olives, peanuts,
fruits where the skin
is not eaten, grass for
animals

Group C (2)
Gardens, vegetables
for cooking fruits
for the conservation
industry

Group D (3)
Other plant (unlimited irrigation)

Effluent quality (4)

 

 

 

 

BOD5 - Total

60

45

35

15

BOD5 - Filtered

-

-

20

10

Suspended Solids

50

40

30

15

Dissolved Oxygen

0.5<

0.5<

0.5<

0.5<

Coliform Counts/ 100 ml

-

-

250

12(80%) & 2.2(50%)

Residual Chloride

-

-

0.15

0.5

Mandatory treatment

 

 

 

 

Sand Filtration (5)

-

-

-

Required

Chlorination - Minimal Contact Time, Minutes

-

-

60

120

Distance (m)

 

 

 

 

Residential Areas

300 (sprinkling)

250

-

-

Paved Roads

30

25

-

-

Comments:

(1) The criteria are not limited to the treatment method; however, for an oxidation pond they should be adapted to a retention time higher than 15 days.

(2) Irrigation should be terminated two weeks before the pick-up season, and no fruits that fall on the ground should be taken.

(3) Observation and examination frequency in accordance with the irrigation season.

(4) The criteria should satisfied at least  80% of the cases.

(5) Sand or equivalent filtration.

(6) All examinations should be done in official governmental laboratories.

The information presented in this paper is available on the Middle East Wastewater Use Clearinghouse (2000) Internet site, http://weather.nmsu.edu/hydrology/wastewater/. The site also includes links to related projects and information on wastewater use in agriculture in Egypt, Israel, Jordan and the Palestinian Authority. Information on problems and solutions associated with the use of wastewater with different irrigation systems is also presented on the Internet site.

CONCLUSION

 

Wastewater regulations and standards of use vary among the Middle East countries. These regulations are based on scientific information and also on public perceptions about wastewater. The information on the use of wastewater in agriculture is vast, covering a range of health issues, production issues related to crop/water requirements and the type of irrigation system to use for each crop, and finally technical issues regarding the maintenance of the irrigation systems. This information is not found on any centralized database.

An Internet site is the only cost- and time-efficient method to disseminate wastewater information to a large group of people covering a large geographic area and at the same time keep the information current. Furthermore, an Internet site or a CD disk generated from an Internet site is probably the most economical way to educate people about wastewater use in agriculture.

It is hoped that both policy makers and extension agents will use Internet sites to compare their system of regulations and use of wastewater in agriculture with those of their neighbors or of other water-scarce countries. Knowledge gained from practical experiences and new information will enable users to make informed choices and positive change that will lead to more efficient use of water resources.

REFERENCES

 

1.   Appropriate Technology Consortium (ATC). (2000). Online. Available:  http://www.gal‑soc.org/atc.html.

2.      Asano, T., & Mills, R.A. (1990, January). Planning and analysis for water reuse projects. Journal American Water Works Association, 38-47.

3.   The Consortium of Institutes for Decentralized Wastewater Treatment (CIDWT). (2000). Online.  Available:  http://www.dal.ca/~cwrs/cdwt/.

4.      Gerba, C.P., Wallis, C., & Melnick, J.L. (1975). Fate of wastewater bacteria and viruses in soil. J. Irrig. Drainage Div., ASCE 101 (IR3), 157-174.

5.   Lesikar, B. (1999, August). On-site wastewater treatment systems: Subsurface drip distribution (Publication No. L‑5237). Online. Texas Agricultural Extension Service. Available: http://agpublications.tamu.edu/pubs/eengine/l5237.pdf.

6.   Middle East Wastewater Use Clearinghouse. (2000). Online.  Available: http://weather.nmsu.edu/hydrology/wastewater/.

7.   National Small Flows Clearinghouse (NSFC). (2000). Online.  Available:  http://www.estd.wvu.edu/nsfc/NSFC_homepage.html.

8.   Oron, G., Campos, C., Gillerman, L., & Salgotm M. (1999). Wastewater treatment, renovation and reuse for agricultural irrigation in small communities. Ag. Water Management, 38, 223-224.

9.   World Health Organization. (1989). Health guidelines for the use of wastewater in agriculture and aquaculture (Technical Report Series 778, pp. 1-74). Geneva: Author.

 



[1] Professor Dept. of Agronomy & Horticulture, New Mexico State University, Las Cruces, New Mexico

[2] U.S. Program Director, Middle East and Mediterranean Desert Dev. Prog., San Diego State University

[3] Asst. Dir. SW TDI, New Mexico State University, Las Cruces, New Mexico