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 |
Group A |
Group B |
Group C |
|
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 |
N/R |
|
Equivalent water treatment plant |
Required |
N/R |
N/R |
*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 |
Group A |
Group B |
Group C (2) |
Group D (3) |
|
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
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projects. Journal American Water Works
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3. The
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(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.,
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B. (1999, August). On-site wastewater
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