SANITATION IN EGYPT: THE WAY FORWARD. Seville Spain November 2007

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1 ll International Congress SANITATION IN EGYPT: THE WAY FORWARD Prepared By Fatma El-Gohary Seville Spain November 2007

2 BACKGROUND It is estimated that unsafe water and lack of basic sanitation and hygiene claim the lives of more than 1.5 million child under five years old every year, most of them from developing countries. This tragic statistic underscores the world s commitment to meet its Millennium Development Goal (MDG), which aims to halve the proportion of people without sustainable access to safe drinking water and basic sanitation, by the year 2015.

3 CURRENT STATE OF SANITATION COVERAGE WORLDWIDE Over the period , an estimated 1.2 billion people gained access to sanitation. To meet the MDG sanitation target, the rate of improvement over the past 15 years would have to double between now and Developed/Developing Disparities in Sanitation Coverage The analysis shows that in many developing parts of the world, the sanitation target is at risk since all management efforts and levels of sanitation coverage are failing even to keep pace with population growth. Thus the trend of the rising population must be taken into consideration while setting targets for sanitation coverage in these countries. It is becoming increasingly urgent to close the gap between those who have sanitation services and those who do not. The unhealthy conditions of those lacking sanitation cannot be ignored because sanitation-related diseases and polluted water sources often have devastating social, economic and environmental effects on all residents.

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5 Central and Eastern Europe and the Commonwealth of Independent States (CEE/CIS)

6 Urban/Rural Disparities in Sanitation Coverage Sanitation coverage in urban areas was more than twice as high as in rural areas in 2004 (80 per cent in urban areas versus 39 per cent in rural areas). Of the 2.6 billion people currently without access to basic sanitation, 2 billion (77 per cent) live in rural areas. The urban-rural disparity is largest in South Asia, where only 27 per cent of the rural population is served, compared to 63 per cent in urban areas. Only in industrialized countries is urban and rural coverage comparable.

7 CURRENT STATE OF SANITATION COVERAGE IN EGYPT The water and sanitation sector in Egypt has faced formidable challenges over the last three decades, such as: High overall population growth rate (2.1%), Even higher urban population growth rate (3.8%) and, The unbalanced distribution of the people (most of the population is concentrated in only 4% of the total area of Egypt, in the Delta & Nile valley) These constraints developed a situation which has not only increased pressure on water resources, but also created a tremendous additional demand for water and sanitation infrastructure Expected Population Growth in Egypt

8 SANITATION COVERAGE IN EGYPT (Cont.) It has been reported that up to LE. 30 billion have been invested during the last twenty years to improve the water sector. However, most sector investment was directed to the provision of drinking water. In Egypt access to improved sanitation is less than half that for water. Also, the rate of sewerage connection varies, with impressively high rates (more than 90 percent) in some cities such as Cairo, to less than 5% in rural areas. This gap matters, not just because access to sanitation is intrinsically important, but also because the benefits of improved access to water and to sanitation are mutually reinforcing. High levels of pollution in areas without appropriate sanitation systems undermine the potential health and environmental benefits of near universal access to water.

9 SANITATION COVERAGE IN EGYPT (Cont.) On the sanitation side, it became clear that investment has been primarily directed to large sanitation infrastructure. The high capital, operation, and maintenance costs of this infrastructure have made it more difficult to recover the full cost from users and to make wastewater utilities financially sustainable. High costs are often the result of implementation of inappropriate technologies. Large scale conventional treatment systems have been viewed as the only option for dealing with domestic wastewater. A large proportion of the cost of these systems is tied up in the pipes, pumping equipment and earth works required to install this infrastructure, making it an expensive option.

10 FACING THE CHALLENGE To achieve the Millennium Development Goals (MDGs) for water and sanitation, the Government of Egypt has embarked on an ambitious program, more focused towards maintaining sustainable sanitation services for peri-urban and rural areas. In light of the growing realization that weak institutional framework is a major contributing factor to the poor level of water and sanitation services, substantial efforts have been undertaken to develop a nationwide sector reform program. By the beginning of the year 2007, the Government of Egypt allocated LE 20 billion for the implementation of sanitation projects in the coming five years.

11 FACING THE CHALLENGE (Cont.) However the magnitude of the sanitation problems in rural Egypt is much larger than the scope of the projects planned so far. There are about 4,600 villages and 2,000 housing clusters (Nag, Ezba, Kafr), which are expected to accommodate around 40 million people by the year FUTURE PROJECTION Year Population People served People not served Million 18 Million 42 Million Million 39 Million 44 Million

12 Consequently: There is an urgent need, in both the short and long term, to address this problem and find appropriate solutions, which are both economically and technically feasible for Egypt. Such solutions must also look at ways to reduce the health hazards and improve the overall environmental conditions of the people of rural Egypt. To do this successfully, requires good planning which in turn should be based on national policy, developed specifically to protect water resources, health of the people and sustain development.

13 A Strategic View of Wastewater Treatment in Egypt Recently, there is a growing realization between experts and decision makers in Egypt that there is a need to go beyond traditional classification between small, appropriate and modern/advanced technologies and to develop rural and peri- urban sustainable sanitation with a mix of scales, strategies, technologies, payment systems and decisionmaking structures, that better fits the people for whom these systems are designed. The prerequisites for attaining sustainable sanitation are: Investment efficiency and Operational efficiency The strategic measures for achieving investment efficiency are: designing and installing facilities so that they function according to the designs and cost sharing arrangements agreed upon with users. The strategic measures for achieving operational efficiency are: To ensure that the installed facilities are used as they were intended so that beneficiaries gain optimum health and other benefits. To provide long-term and effective management of the facilities. This includes ensuring that the sufficient resources will be available to cover operations and maintenance during the active life of the physical infrastructure.

14 TECHNOLOGY OPTIONS There is a wide range of innovative sanitation technologies to choose from: In some cases it may be preferable not to install sewers, but to continue to use existing on-site sanitation technologies such as cesspools and septic tanks. In other cases, sewer network may be installed only for a block of houses connected to a communal septic tank. Under certain circumstances, however, the high-cost solution of connecting to a citywide sewerage network is the only feasible technical solution.

15 On-site Treatment Onsite wastewater disposal systems present a sound method of household waste management in communities where the population density is low, land is available for system construction, and where soil and groundwater conditions permit system use. On-site sanitation is effective when little or no piped water is available. It is used for wastewater collection and treatment at the level of a household, an apartment or a community. On-site systems use either a septic tank or pit latrines. Septic tanks and pit latrines are low-cost technologies that allow construction, repair, and operation by local communities or homeowners and effectively reduce public health problems Septic tank is a watertight tank that collects wastewater from toilets, showers, sinks, and other household utilities through a pipe. Solids settle on the bottom and the liquid flows out of the septic tank into a drainage field or overflows into a drainage system. The required effluent disposal area depends on flow rate and local soil infiltration. The effects of these flows on the quality of the ground water must be considered. Accumulating solids have to be periodically removed from the tank. In properly designed septic tanks, the soil will remove the remaining BOD, suspended solids, bacteria, and viruses from the effluent. In a pit latrine, the solids settle but the liquid seeps directly into the soil. However, the congested nature of many peri-urban settlements restricts the space available for pit latrines and septic tanks. Furthermore, in densely populated areas, the volume of generated wastewater may exceed the capacity for ground

16 Off-site Treatment Off-site options for treatment of municipal wastewater should be considered when on-site treatment could entail direct risks to health or to ground water or risk of faecal contamination or eutrophication of coastal waters, as in more densely populated coastal areas. The construction cost of wastewater collection is relatively high, depending on slopes, soil, and ground water level. Gravity sewers are preferred because of their lower operation and maintenance costs compared to pumped systems, therefore, Intermediate wastewater collection technologies can be applied where conventional wastewater collection systems may be difficult and expensive to construct in densely populated, low-income areas

17 CENTRALIZED /DECENTRALIZED SYSTEMS Centralized Wastewater Management Recent research and development in the field of wastewater management suggests that centralized wastewater management is unsustainable from the social, environmental and financial point of view for the following reasons: Recent studies indicated that it may be not possible, due to economic reasons, to provide sewerage facilities for all residents of rural and peri-urban areas, either now or in the near future. Conventional sewerage is expensive (cost 80-90% of the entire wastewater collection and treatment) and water intensive and therefore its application for small communities in developing countries cannot be justified. Consumption of 100 l /cd is basic requirement for problem free operation of conventional sewerage systems. Therefore, these systems are not appropriate for small communities where water supply is intermittent and only limited amounts of water are available. Centralized management of wastewater concentrates sewage outflows to point source discharges overloading the receiving environment that cannot cope in case of breakdown.

18 Centralized Wastewater Management (Cont.) Centralized systems increase the risk to humans and the environment during system failure or severe overload of treatment works. The probability of failure of a system serving two million inhabitants is significantly higher than the probability of simultaneous failure of several systems serving the same population. Centralized management removes the wastewater from the generating community to as far away to where the treatment works are situated. This practice significantly increases the cost. Often wastewater must be pumped from various drainage basins to the central treatment plant through long and large trunk sewers. By transporting the wastewater away from the generating community, several reuse opportunities can be lost. Reuse opportunities are often located within the generating community for landscaping or near the generating community for agriculture. Reuse of treated effluent within a centralized system requires construction of an extensive pressure mains, pumping stations, storage and distribution network for bringing the treated effluent back to the to the locations where it will be used. As a result, the focus of the field of wastewater management should change from the construction and management of regional sewerage systems to the construction and management of decentralized wastewater treatment facilities.

19 Decentralized Wastewater Management (DWWM) DWWM implies managing wastewater as close as practical to where it is generated and to where its potential beneficial reuse is located. The wastewater management system for a community may comprise several smaller subsystems for collection, treatment and reuse. The size of each subsystem is determined by the administrative, drainage boundaries, and other prevailing social and economic conditions. Dividing such areas into self-contained zones eliminates the need for expensive pumping stations and interceptor sewers required to serve the whole area with a conventional sewerage system. Decentralization is receiving increased attention from wastewater professionals and researchers because of its potential for cost reduction, efficient management, reduced environmental hazards in case of accidents, more reuse opportunities and many other advantages

20 Decentralized Wastewater Management (DWWM) (Cont.) Decentralized management allows the application of various cost effective management options which are tailored to the prevailing conditions in the various sections of the community. Decentralization requires the choice of efficient and affordable wastewater treatment technologies which can be placed close to the human settlements without causing nuisance to the community. Developing such treatment technologies requires extensive research and utilization of both simple and sophisticated technologies which may prove effective and efficient. There are well established processes of conventional and non-conventional wastewater treatment. The Upflow Sludge Blanket (USB) reactor seems to offer great opportunities for efficient and safe domestic wastewater treatment

21 Conventional Mechanical Systems Consist of a combination of biological and physical processes, employ tanks, pumps, blowers, rotating mechanisms, and/or other mechanical components as part of the overall system

22 Conventional Mechanical Systems (Cont.) These systems include suspended growth, fixed growth, and combinations of the two. This category also includes some sludge management alternatives, such as digestion, dewatering, and composting systems and appropriate disposal information. Disadvantages Complex process design (many process units) Expensive equipment involved No local spare parts available High energy demand (aeration): 1 kwh / kg COD removed Skilled personnel required Very high production of excess sludge

23 Identification of cost-effective technologies Pond systems Advantages - Low investment costs if land price is low - Do not consume energy - Relatively easy to maintain -Efficient for pathogen removal Disadvantages - High demand of flat land - Often accompanied with odor nuisance - Generally applied as off-site treatment (conveyance required) - Evaporation of large volumes of fresh water - Increase of water salinity

24 On going Activities In Egypt In recognition of the acute nature of the sanitation problem in periurban and rural areas of Egypt, the Water Pollution Control Department (WPCD) of the National Research Centre (NRC) in cooperation with Wageningen University, in the Netherlands and other European and Arab countries, and within the framework of multi-lateral and bi-lateral cooperation has executed several R&D projects, the main objectives of which are: Development of an integrated cost-effective wastewater treatment schemes for peri-urban, rural areas and tourist resorts The ultimate goal of these projects is protection of the environment and resources conservation. For these treatment schemes anaerobic treatment was used as a first step followed by a low cost treatment post treatment step

25 Basic setup of anaerobic sewage treatment

26 Why Anaerobic Treatment? Anaerobic treatment offers a cost effective alternative for: Removing suspended organic matter Removing soluble organic matter Solubilizing plant nutrients (N / P) Production of energy ( kwh / kg organic matter removed) Reduction of excess sludge production by 90% No use of fossil fuels for treatment (saving 1 kwh / kg organic matter) Production of soil conditioner Reduction of Helminth eggs Response rapidly to substrate addition after long period without feeding Can accommodate higher volumetric loadings rates.

27 Why Anaerobic Treatment? Cont. The major concerns with anaerobic processes are: their longer start-up time their sensitivity to possible toxic compounds, the potential for odour production, and corrosiveness of the digester gas. However, with the development of a variety of new high rate anaerobic treatment processes, such as: the original UASB process and its modifications the anaerobic baffled reactor (ABR) the anaerobic migrating blanket reactor (AMBR) process A break-through has been made in the field of anaerobic treatment of sewage Of these anaerobic processes, the UASB process is the one most commonly used, with over 500 installations treating a wide range of industrial wastewater and domestic wastewater From the accumulated experience, it became obvious that the key to successful application of anaerobic treatment is to un-couple the hydraulic retention time (of wastewater) and the solids retention time (of active biomass) in the reactor system.

28 UASB REACTOR The most characteristic device of the UASB reactor is the phase separator. This device is placed at the top of the reactor and divides it into a lower part, the digestion zone and an upper part, the settling zone. The wastewater is introduced as uniformly as possible over the reactor bottom, and travels in an up-flow mode through the sludge blanket into the settling zone.

29 UASB REACTOR (Cont.) Due to the inclined walls of the phase separator, the area for the liquid flow in the settling zone increases. Consequently the up-flow velocity of the waste water decreases. As a result flocculation and/or sedimentation of the flocks into the settling zone take place. At a certain stage the weight of the sludge accumulated in the phase separator will exceed the frictional force that keeps it on the inclined surface and it slides back into the digestion zone to become, once again, part of the sludge mass that digests the influent organic matter. Thus, the presence of a settler on the top of the digestion zone enables the system to maintain a large sludge mass in the UASB reactor, while an effluent essentially free of suspended solids is discharged. The biogas produced under anaerobic conditions serve to mix the contents of the reactor as they rise to the surface. The rising gas also helps to form and maintain the flocks. The gas is trapped in a gas collection dome located at the top of the reactor.

30 Upgrading effluents of anaerobic treatment processes Anaerobically treated wastewater is usually not complying with the Egyptian standards regulating use of treated wastewater for irrigation purposes or its disposal into receiving water bodies. Therefore, some form of post treatment would be necessary to provide effluent polishing. The use of Algal ponds (AP); Lemna (Duckweed) ponds (LP); Engineered wetland, Fishponds, and a compact Rotating Biological Contactor (RBC) to upgrade the UASB effluent has been investigated by WPCD. Very promising results have been

31 Waste stabilization Pond (32000 m3/d, Balana City ASWAN) COD total (mgo2/l) Sewage Treated effluent BOD total (mgo2/l) Sewage Treated effluent TSS (mg/l) Sewage Treated effluent Influent Irrigated forest Maturation pond Facultative pond Anaerobic pond

32 Full Scale Up-flow Anaerobic sludge Blanket (UASB) Followed by Trickling Filter(3000 m3/d) in Nahati (Gharbia) COD total (mgo 2 /l) Sewage Treated effluent BOD total (mgo 2 /l) Sewage Treated effluent TSS (mg/l) Sewage Treated effluent UASB2 UASB1

33 Full Scale Up-flow Anaerobic sludge Blanket (UASB) Followed by Trickling Filter(3000 m3/d) in Sanhour (Fayoum) COD total (mgo /l) 2 BOD total (mgo /l) 2 TSS (mg/l) Sewage Treated effluent Sewage Treated effluent Sewage Treated effluent Drain Influent Trickling Filter UASB

34 CONCLUSIONS From the available knowledge, it can be concluded that the integration of anaerobic process with a low-cost post treatment step represents a sustainable system for wastewater reclamation. Research should be encouraged to improve the efficiency of the integrated system for pathogenic organisms removal. This can be achieved by better understanding of the fate of pathogens in the different treatment units. Needless to say, that sanitation programs depend critically for their success on effective public awareness and mobilization through information, education and communication. Experience over the past decades demonstrate that even the technically best-designed programs fail, if intended beneficiaries are not adequately consulted, informed, educated or mobilized.

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