Wastewater Management: A Case of Reducing Wastewater Release into the Environment in Urban Centres

Introduction

Every person has a right to clean and healthy environment. A healthy environment is crucial to delivering Vision 2030, which is a long-term development blueprint. However, one of the greatest challenges of the twenty first century is the incessant of supply of clean drinking water for the millions of the living things all over the world. Therefore there is need to provide the new approach to wastewater management and to deal with the issues in an environmentally-conscious manner. Inappropriate or absent wastewater management deteriorates drinking water sources and natural environment and endangers human health. It is a major problem in numerous countries which demands taking appropriate and well considered actions adapted to the specific environment and economic welfare.

Water scarcity can be addressed through improvement of the efficiency of consumptions and seek sustainable alternative sources. Several approaches exist among them efficient and effective wastewater management and reuse to supplement fresh water and keep environment clean. The reuse of wastewater can be a strategy to release freshwater for domestic use, and to improve the quality of river waters used for abstraction of drinking water (by reducing disposal of effluent into rivers).

Aspects of wastewater management are explored with integrated perspective in that a holistic view of the entire wastewater system is required for proper wastewater management, starting from the wastewater generation until the ultimate disposal schemes. The functional elements of integrated wastewater management system are generation, collection, treatment (including sludge treatment) and disposal and reuse. A successful wastewater management decision requires a comprehensive, impartial evaluation of wastewater management approaches.

Densely populated or ecologically sensitive areas may require wastewater management therefore there is need for a well maintained wastewater collection system to help avert wastewater infiltration and exfiltration into the environment due to the leaks which majorly results to fresh water pollution. However, other alternative wastewater management such as wastewater reuse, wastewater trade as well as wastewater treatment can be embraced to help in solving the problem of wastewater pollution facilitating environment and human well- being.

Dealing with waste as a resource is becoming a crucial factor in sustainable use of natural resources in that, wastewater is not only a source of water for different purposes but also a source or organic matter, nutrients and energy.

Wastewater types and sources

Wastewater is the liquid waste resulting from all activities using water supply. It is produced in every human society. Wastewater can be divided into different groups, according to its origin (e.g. surface runoff, grey and black waters). Different types of wastewater are managed with different collection, treatment and disposal/reuse technologies and techniques.

Types of waste water types

There are different wastewater types that need to be managed in order to curb environment pollution. These types are as follows;

Grey water

Grey water is all the wastewater produced in the home except toilet waste (Ridderstolpe, 2004). Grey water from dish washing, showers, sinks and laundry comprise the largest part of residential water. Amount of grey water produced in a household can vary greatly due to different water consumption patterns and this is always linked to social status of an area for example, water consumption in poor areas is about 20- 30 litres per day while a person in a richer area can generate several hundreds of litres per day (Ridderstolpe, 2004). Grey water normally contains low levels of nutrients compared with normal wastewater from water- borne systems. Levels of nitrogen and other plant nutrients are always low, but in some grey water high concentration of phosphorus can be found (Swedish EPA, 2002). Grey water management can be achieved through undertaking of water conservation measures as well as managing soaps, cleansers and other household chemicals. To reach and control a conservative use of water, water saving equipment installed in a house should be combined with economic incentives e.g. charging system for water consumed.

Grey water treatment and reuse for example as part of ecological sanitation (ecosan) concepts, is a relatively new concept which is often considered as a more simple form of wastewater treatment, but there is still a lack of experience. Most grey water treatment technologies are derived from conventional wastewater treatment and were not developed specifically for grey water treatment. The quantity of grey water generated depends on the income level of the household. As a general rule: the richer the people, the more grey water they produce. Households without in-house water connection produce grey water which is more concentrated than wastewater from wealthy areas, due to the lower water consumption and existing reuse practices: Water is first used for personal hygiene, then for washing clothes and then for washing the floor.

Black water

According to Consortium of Institutes for Decentralized Wastewater Treatment (CIDWT, 2004), black water is portion of the wastewater stream that originates from toilet fixtures, dish-washers and food preparation sinks. Black water and its quantity depend on the flush toilet type. Normally the volume varies between 40-60 L/capita/day.

Storm water

Urbanization has well known adverse hydrological effects (Leopold, 1968); (Klein, 1979). Increase in the peak rate of storm water run- off due to introduction of impervious areas and to improved drainage system has been the main management focus (Ferguson, 1990). Urban areas consists of high density residential (flats) hence limited unpaved open spaces are left to carter for the infiltration of the storm run- off which carries with it oil from vehicle oil leaks therefore the run- off is directed into the storm drainages which eventually pollute fresh water.

Sources of waste water

Wastewater is generated from different sources and these are household wastewater (domestic) and water from the rain which are untapped.

Domestic waste water

Domestic wastewater originates from domestic household activities as well as water that are discharged from commercial and business buildings and institutions. Domestic wastewater consists of liquid discharge from sanitary facilities, bathing, laundry and cooking.

Surface water run- off

During the past few years it has been recognized that run off from storms is not rain water in terms of quality. Storm runoff contains substantial quantities of impurities so much that it is a more serious source of pollutants in many areas than are municipal wastes. Urban runoff can contribute to a variety of problems including direct pollution of receiving waters, overloading of treatment facilities and impairment of sewer and catch basin functions (James & Sartor, 1974).

Wastewater management process

For a successful management of wastewater, there is need for wastewater collection system for channelling wastewater to the required area that is sewerage plant for its treatment to prevent wastewater discharge into the environment while in its raw form to avoid environmental degradation.

Wastewater collection systems

There are different types of wastewater collection systems used in channelling wastewater. These are:

Sewer system

Wastewater collection systems are responsible for collection and transmission of liquid wastes to a central treatment facility. Like a distribution system for water supply, the collection system resembles a tree that branches out from the treatment plant to collect the wastewater from individuals. Wastewater from individual homes enters the collection system from a service line. Complexity of the system depends on the size of the community and the type of the system selected. None the less some storm water enters sanitary sewers through cracks, particularly in older lines, and through roof and basement drains. Due to the much smaller volumes of wastewater that pass through sanitary sewer lines compared to combined sewers, sanitary sewer systems use smaller pipes and lower the cost of collecting wastewater.

Drainage systems

Conventional drainage systems are designed to achieve a single objective — flood control during large, infrequent storms. This objective is met by conveying and/or detaining peak runoff from large, infrequent storms. Drainage systems designed to meet a single flood control objective fail to address the environmental effects of increases in runoff volume and velocity caused by development, as well as flow peaks. Increased runoff from small, frequent storms erodes urban streams and washes eroded sediment and other constituents from the urban landscape into downstream receiving waters, often damaging adjoining property and impairing their use by people and wildlife. Today‘s drainage systems must cost effectively manage flooding, control stream bank erosion, and protect water quality. To do this, designers must integrate conventional flood control strategies for large, infrequent storms with three basic storm water quality control strategies for small, frequent storms that is: infiltrate runoff into the soil, retain/detain runoff for later release, convey runoff slowly through vegetation

Combined (sewer and drainage) systems

Many of the earliest sewer systems were combined sewers, designed to collect both sanitary wastewater and storm water runoff in a single system. These combined sewer systems are designed to provide storm drainage from streets and roofs to prevent flooding in cities. Later, lines were added to carry domestic wastewater away from homes and businesses. Early sanitarians thought that these combined systems provided adequate health protection. We now know that the overflows designed to release excess flow during rains also release pathogens and other pollutants.

Wastewater treatment

Waste treatment is now the world’s most common “biotechnology” (Wagner et al., 2002); in the US alone, over 15 000 wastewater treatment facilities collectively process 100 billion litres of wastewater per day (Gabriel, 1999). Despite the massive scale of the wastewater treatment industry, only modest advances have occurred in our basic understanding of these biological treatment processes during the past century or so.

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Wastewater treatment systems were first developed in response to the adverse conditions caused by the discharge of raw effluents to water bodies. With this approach, treatment is aimed at the removal of biodegradable organic compounds, suspended and floatable material, nutrients and pathogens.

Wastewater treatment technologies can be designed to provide low cost sanitation and environmental protection. Wastewater treatment systems are classified into different principal types and these are: mechanical treatment system, aquatic system and terrestrial system.

Mechanical Treatment Technology

Mechanical systems utilize a combination of physical, biological, and chemical processes to achieve the treatment objectives. Using essentially natural processes within an artificial environment, mechanical treatment technologies use a series of tanks, along with pumps, blowers, screens, grinders, and other mechanical components, to treat wastewaters. Flow of wastewater in the system is controlled by various types of instrumentation. Sequencing batch reactors (SBR), oxidation ditches, and extended aeration systems are all variations of the activated-sludge process, which is a suspended-growth system. The trickling filter solids contact process (TF-SCP), in contrast, is an attached-growth system. These treatment systems are effective where land is at a premium.

Aquatic Treatment Technologies

According to Source Book of Alternative Technologies for Freshwater Augmentation in Latin America and the Caribbean of 1997, Facultative lagoons are the most common form of aquatic treatment-lagoon technology currently in use. However, there are other technologies such as aerated lagoons and constructed wetlands.

Terrestrial Systems (Land Treatment System)

Land treatment is the controlled application of wastewater to the soil where physical, chemical, and biological processes treat the wastewater as it passes across or through the soil. Terrestrial treatment systems include slow-rate overland flow, slow-rate subsurface infiltration, and rapid infiltration methods. They depend upon physical, chemical, and biological reactions on and within the soil. Slow rate overland flow systems require vegetation, both to take up nutrients and other contaminants and to slow the passage of the effluent across the land surface to ensure maximum contact times between the effluents and the plants/soils. Slow-rate subsurface infiltration systems and rapid infiltration systems are “zero discharge” systems that rarely discharge effluents directly to streams or other surface waters. Each system has different constraints regarding soil permeability. In slow-rate systems, either primary or secondary wastewater is applied at a controlled rate, either by sprinklers or by flooding of furrows, to a vegetated land surface of moderate to low permeability. The wastewater is treated as it passes through the soil by filtration, adsorption, ion exchange, precipitation, microbial action, and plant uptake. Vegetation is a critical component of the process and serves to extract nutrients, reduce erosion, and maintain soil permeability. Overland flow systems are a land application treatment method in which treated effluents are eventually discharged to surface water. In rapid infiltration systems, most of the applied wastewater percolates through the soil, and the treated effluent drains naturally to surface waters or recharges the groundwater. Wastewater is applied to soils that are moderately or highly permeable by spreading in basins or by sprinkling. Vegetation is not necessary, but it does not cause a problem if present. The major treatment goal is to convert ammonia nitrogen in the water to nitrate nitrogen before discharging to the receiving water. Subsurface infiltration systems are designed for municipalities of less than 2,500 people. They are usually designed for individual homes (septic tanks), but they can be designed for clusters of homes. Although they do require specific site conditions, they can be low-cost methods of wastewater disposal (UNEP, 1997).

Purpose of wastewater management

According to the United Nations Population Fund (UNFPA), human impact on the environment is a function of population size, per capita consumption and the environmental damage caused by the technology used to produce what is consumed (UNFPA, 2001) The environmental problems associated with urban areas are a consequence of the number of people‘s activities and Urban area residents are mostly involved in environmental degradation such as pollution of portable water from wastewater. The environmental consequences of population growth are amplified by the growth in numbers. Rapid increase in population in urban centres usually lead to unprecedented sprawl of informal settlements; outstripped city‘s delivery of social services. The following are the facilitators of need for wastewater management.

Rapid population growth

The world‘s urban population reached 2.9 billion in 2000 and is expected to rise to 5 billion by 2030. Whereas 30 per cent of the world population lived in urban areas in 1950, the proportion of urban dwellers rose to 47 per cent by 2000 and is projected to attain 60 per cent by 2030 (United Nations, 2001). Population growth will be particularly rapid in the urban areas of less developed regions, averaging 2.4 per cent per year during 2000- 2030, consistent with a doubling time of 29 years. Rural-urban migration and the transformation of rural settlements into cities are important determinants of the high population growth expected in urban areas of the less developed regions over the next thirty years. In combination with the universal reduction of fertility levels that are expected to occur in the future (United Nations, 2001). The accumulation of people, their consumption patterns, travel behavior and their urban economic activities have a large impact on the environment in terms of resource consumption and waste discharges as implications of rapid urban growth include increasing unemployment, environmental degradation, lack of urban services, overburdening of existing infrastructure and lack of access to land, finance and adequate shelter (UNCHS, 2001). Managing the urban environment sustainably will therefore become one of the major challenges for the future as population is a major driver of environmental change in Nairobi and as such is a determinant of other parameters such as solid-waste-generation rates, land-use patterns and settlement, and water consumption.

Urbanization

Urbanization is one of the most important demographic trends of the twenty-first century, and growth is particularly rapid in lower-income countries. The majority of urban growth is associated with the rapid expansion of smaller urban centers and peri-urban developments which are unplanned and informal, with community members and informal-sector developers taking advantage of the fact that the regulatory capacity of government authorities is weak, particularly in those areas that are outside official municipal boundaries.

In urban and peri-urban areas, increasing populations, combined with increasing water consumption and a proliferation of waterborne sanitation, create widespread wastewater disposal problems. In many cases, wastewater is discharged locally onto open ground and vacant plots, creating ponds of foul-smelling stagnant water. Health risks are increased by the fact that household and surface water drainage systems are invariably combined, so that floodwater becomes contaminated with excreta (United Nations, 2001).

Social inequality of the population

Human well-being requires a healthy environment. Inadequate sanitation practices negatively impact the environment. For poor families living in congested urban slums and in villages, the lack of any sanitation facility means that waste lies on the streets, clogs the drains and creates an immediate local hazard which is one of the major pollutants and clogging of drainage systems.

Settlements are generally inhabited by communities of different economic status relating to land prices, which are affected by location in relation to the city, and which are considerably higher than in rural areas.

Many industries locate on the edge of the city because land there is relatively cheap and not subject to stringent development controls and, at present, the wastes they produce rarely receive adequate treatment. The limited infrastructure facilities that are provided are often inadequate, and the result is a poor and often deteriorating environment. Provision of infrastructure and services tends to occur in a piecemeal fashion, either through the efforts of residents themselves or as a result of pressure from civil society on elected representatives and government officials. However, even where household sanitation and localized drainage facilities do exist, often there is a lack of a comprehensive system for the collection and disposal of wastewater (United Nations, 2001).

Environmental degradation

Urban areas do not have only local environmental impacts but also large so-called ‗ecological footprints‘ (WWF, 2000). Waterborne sewage uses scarce freshwater resources and may contaminate surface waters when it is discharged into the environment without adequate treatment – thus endangering downstream users and aquatic resources. The lack of infrastructure and services and effective systems for managing wastewater has led to widespread pollution of surface water and groundwater and deterioration in environmental health conditions. The greatest impacts are upon the health and livelihoods of poor communities, who often inhabit low lying and marginal land, for instance wetlands and alongside drainage channels, which are polluted with excreta and other wastewater (Birley, 1998). In addition, Pollution from urban run-off and untreated discharges of industries has adversely affected many water bodies, leaving many cities with unsafe water supply.

Segregation of wastewater at source

Domestic wastewater consists of ―black‖ water, the mixture of water and faeces flushed from Water Containers and pour-flush toilets, and ―grey‖ water, the sullage from kitchens and bathrooms. Grey water contains much lower pathogen levels and has a lower oxygen demand than black water and therefore represents a much smaller health and/or environmental threat. Grey water and black water are produced separately, and ensuring that they remain separate can facilitate management of the two wastewater streams. This option may be considered where it is possible to dispose of black water to a leach pit or septic tank followed by a soak away. Grey water can then be used for irrigation or discharged into a local watercourse with little or no treatment (Weisburd, 2000).

Theoretical Framework

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Holistic approach

Sustainable management of water requires the involvement and incorporation of stakeholders during decision making stage when formulating policies and legislations and establishment of effective water institutions, development of low water usage or dry sanitation system, rain water harvesting and extensive use of resource recovery and reuse technique for waste water (Lens et al, 2001). The holistic approach sees waste as a resource and its management linked to that of water resources and of nutrients in that resource recovery and reuse result in financial incentives which could be used to cover part of the cost of waste water treatment (FAO, 1999). There has also been an increased emphasis on a more holistic approach to waste disposal that stresses the benefits of reducing the strength or quantity of waste at source and, where possible, recycling or re-using it close to the point where it is produced (Kalbermatten, 1999).

Ecosystem- Based Management and Wastewater

Ecosystem- based management is an integrated approach to management that considers entire ecosystem, including humans. The goals of ecosystem-based management are to maintain an ecosystem in a healthy, productive and resilient condition so that it can provide the services humans want and need. It acknowledges interconnectedness between systems such as air, land and water and integrates ecological, social, economic and institutional perspectives, recognizing their strong interdependences (COMPASS, 2005). Tackling the broad and cross- sectoral nature of wastewater and its management successfully and sustainably requires an ecosystem based perspective, applied to integrated natural resource management.

Due to the environmental changes that were experienced in late 1950s and early 1960s brought attention to the world leaders and inhabitants that day- to- day activities are impacting on environmental wellbeing. This scenario thereby led to the enactment and development of international agreements which highlighted the impacts that population has and will have on environment. For example Tragedy of the Commons (Hardin, 1968) and Limits of Growth (Donella et al., 1972) had warned of the possibility that human lifestyle would exceed the capacity of the natural environment to sustain itself. The conformation of this is documented (Meadows et al, 2004) in the book, Limits to Growth which is a 30- year update.

Lack of well managed or protected ecosystems can mean loss of clean water and loss of river waters. Some of key impacts of wastewater discharge on ecosystem relate to eutrophication. Discharge of wastewater into an environment exceeding the natural purification capacity of the environment results in the accumulation of organic materials that cannot be absorbed by ecosystem

Planning for Wastewater Management

From examining how sanitation problems develop in a community, it becomes obvious that they are related to population density relative to the ability of the environment to cope with the wastes generated, and the ability of the community to respond to the problems that arise.

Thus, besides the public health and environmental aspects that have been discussed, there are the social and institutional dimensions that have to be taken into account. These refer to the way communities organize themselves to manage their common affairs, such as arranging collection of household wastes, laying of sewer pipes, and financing these activities. Each community has generally developed means of carrying out these tasks, which may be unique to a particular community or communities in a region. The institutional arrangements in a community evolve with time to meet changes in culture and technology, and may or may not cope with external changes. One such change is rapid urbanization, which leads to rapid population growth in a relatively small area, leading to severe sanitation problems (UNEP, 1997)

Conceptual framework

Wastewater management requires understanding cross- cutting issues and in this case, the study is to indulge into holistic approach in relation to wastewater management which incorporates planning, control and ecosystem-based management approaches. In relation to UNEP GPA ‘Recommendations for decision making on municipal wastewater’ / UNDP/WB ‘Resource Guide in Urban Environmental Sanitation’, cross cutting issues that have been covered are settlement planning, community participation and hygiene promotion and financing and cost recovery. However during undertaking of any development in relation to wastewater management, environment‘s well-being should be considered. Planning appears to be a major and key issue for a community to address. Ideally settlements should be planned ahead of their occupation. Areas should be set aside for treatment and disposal of wastes; community should be involved so that services that are provided is what is needed by community and sanitation services require investment and continuing costs of operation and maintenance. All these measures are crucial in attaining environmental sustainability

Conclusion

Wastewater can be reused for different purposes which may also demand different treatment processes before reuse. Reuse of wastewater can be in different sectors which are; agriculture, industry, residential and urban purposes. Environmental issues have been addressed in a reactive manner as part of project safeguards but not as integrated element of water and wastewater planning, management and development and their enforcement has been generally weak. Wastewater management requires a well-defined environmental policy framework which is harmonized with other relevant sectors such as water, agriculture, industries and others.

The origin of wastewater is water consumption that is; increase in level of water consumption results to large quantities of wastewater generated requiring huge investment in collection and treatment infrastructure. There is therefore an urgent need to develop sustainable management strategies that would control both water and nutrient flows into towns and cities environment which is in this case integrated water and wastewater management; for instance, to improve the traditional urban water management system, water supply and wastewater management have to be closely interconnected so that water is used with minimal withdrawal from and reduced recharge to the environment.

The historical development of wastewater management globally has been characterized by the efforts to solve mainly one problem at a time and Kenya is not an exception. For instance sanitation during first half of 20th century followed by eutrophication of receiving waters for the past 10 or so years, recycling of the nutrients. However after the Dublin conference of water and environment (ICWE) in 1992 in Dublin Ireland, a reversal of the debate occurred where water management was discussed in a more holistic manner (ICWE, 1992). Regulatory policy and institutional framework have not been effective in addressing the threats they suffer such as weaknesses, constraints and shortcomings and this is because;

  • Policies and legislations remain compartmentalized (sectoral) making them difficult to enforce for instance environmental concerns in water act, agriculture act and industrial act are addressed as separate entities.
  • Weak and poor implementation and enforcement of existing policies and legislation is due mainly to lack of political will, expertise, adequate funding, sectoral and institutional coordination in relation to water and wastewater management.
  • Stakeholders are not involved in policy and legislation reforms which state that the state is to encourage public participation in the management, protection and conservation of environment.
  • Ecological data and knowledge is lacking to clarify the linkages between environment and wastewater.
  • Policy and legislation frameworks are not well harmonized with implementation of regional and international agreements.

Recommendations

Ways of reducing wastewater release

To ensure that wastewater release reduction is achieved, there are options that can be adopted and these are; No use, reuse, convert, contain and disperse and this will be achieved through storm water run- off reclamation, wastewater reuse and wastewater recycling and environmental management strategies adoption.

Environmental management strategies

Regulatory controls

Wastewater need to be certified before being disposed of. However strategies such as wastewater reuse controls can be enhanced by government through provision of incentives, enforcement of penalties and ensuring that every premise that generates wastewater holds permits and licenses for its disposal. In addition, water pollution and quality controls is to be achieved through; forbidding discharge of wastewater into environment (fresh water), implementation and enforcement of legislative measures related to wastewater management, restricting discharge of wastewater through penalties and licenses which can be strengthened by formulation, implementation and enforcement of policies, by- laws and laws developed specifically for integration of ecological issues into water resource management.

Lastly, consideration and adoption of water quality management strategies such as presence of incentives for water use minimization, wastewater reuse and wastewater trade can help in reduction of wastewater generation which eventually ends up in environment.

Wastewater Reuse

Humans only require one to two litres of potable water per day yet about 150- 300 litres are consumed in most cities and some believe that this is abusive use of water and recommend that water of different quality to be supplied for different purposes like car washing. Water from bathing, washing machines, dish washers and kitchen could be collected separately and be reused for the purposes that do not require drinking water quality such as gardening.

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Wastewater reuse is one of the wastewater management strategies.  However in urban areas, only 44% reuse their wastewater whereas 56% don‘t. According to field study, majority of household users reuse their wastewater as compared to business people. Wastewater is reused for flashing toilets, controlling dust and cleaning houses. In addition, wastewater can be channelled to dry areas for irrigation; this is because, nitrates and phosphorus present in wastewater is essential for growth of crops. However, there needs to be policy and legislation in place that gives regulatory and control on the quality of wastewater to be used for agricultural purposes. There is also need for reducing water losses both at treatment plant and at the distribution lines as the detection and repair of leaks and an improvement of equipment and production process could greatly reduce water losses and consumption in industries.

Wastewater Management Payment

Payment of wastewater management initiative is essential to realizing wastewater management as funds are required to run the projects that are to be developed or are being developed. The payment can be direct or indirect. Direct payment is when lessee pays for management of his/her wastewater generation and indirect payment can be through permit sand licenses enforcement requirement by the authorities in charge of water resource management and wastewater management to premise lessers. However, there should be policies and legislations in place to ensure the initiative is successful to avoid cases of corruption and lesser transferring the cost to consumers which in this case are lessees.

According to information collected from the field, 56.7% of correspondents are willing to pay for any wastewater management initiative because; it‘s a way of creating extra jobs for jobless population; improvement of environmental condition and having alternative sources of water for activities that doesn‘t require water quality for drinking water such as gardening and cleaning cars. 33.3% are not willing to pay for wastewater management because; they cannot afford; every housing unit should first be connected to wastewater collection system and lastly corruption in existing institutions mandated in ensuring environmental management should be addressed.

Wastewater Treatment

The removal or inactivation of excreted pathogens is the principal objective of wastewater treatment; and treatment to levels proposed by (Blumenthal et al., 2000) Conventional wastewater treatment options (primary and secondary treatments) are often better at removing environmental pollutants than removing pathogens, however, and many of these processes may also be difficult and costly to operate properly in developing country situations. Waste stabilization ponds (WSP), when designed and operated properly, are highly effective at removing pathogens and can be operated at low cost where inexpensive land is available. They are designed to use natural processes of biodegradation, disinfection by sunlight, and particle settling under gravity, to purify the water. They form a series of shallow ponds linked together to maximize retention time. However, WSPs should be designed, operated and maintained in such a way as to prevent disease vectors from breeding in the ponds if the wastewater is to be used for agricultural purposes.

Where effective treatment is not available, it may be possible to consider other options that improve microbial water quality, such as storage reservoirs to partially treat wastewater or water abstraction from surface waters some distance from wastewater discharges where dilution has already taken place.

Gender Mainstreaming

There is need for gender mainstreaming in relation to wastewater management. This is in pertinent to two different perspectives while considering gender and wastewater management. That is; women like to apply or develop short term initiatives when solving a given issue whereas men tend to engage in long term measures to solve the same problem. Secondly, as day-to-day activities in the household are carried out by women most of the time and these activities involve utilization of water hence generation of wastewater; any initiative that is to be developed in relation to wastewater management should incorporate this group of people‘s views.

Policy and Institutional

There should be policy and institutional framework in place with the mandate of ensuring that the owners of any premises whether temporary or permanent, residential or industrial is connected to wastewater collection system to ensure that the wastewater generated is safely channelled to an appropriate disposal site in a sustainable manner. The policy framework must be based on the principles of integrated, sustainable wastewater management and the legislation should be consistent with the spirit and principles contained in the policy; this is possible through issuance of permits and licenses before the building is occupied or used for any activity. There should be establishment as well of enforcement other strategies in addition to setting out penalties for non-compliance. In addition, an appropriate functional institutional framework is required to serve as a vehicle for implementation at national and regional levels. This may require the development of new institutions or restructuring or rebuilding the capacity of existing institutions as well as development of linkages for formal collaboration between institutions of different sectors.

There should be enforcement and implementation of policies which addresses environment as a component. To curb discharge of wastewater into the environment, every person has a duty to cooperate with state organs and other person‘s to protect and conserve environment and ensure ecologically sustainable development and use of natural resources. In addition, the state should encourage public participation in the management, protection and conservation of the environment and eliminate processes and activities that are likely to endanger the environment. However since wastewater pollution is one of the ecological issues/ concerns, wastewater management components should be incorporated in every nation’s constitution to help give added authority in ensuring its attainment to minimize wastewater disposal into the environment more so fresh water bodies. In addition, wastewater components should be added in National Environment Action Plan.

Adoption of Indigenous Knowledge

Different types of indigenous knowledge should be researched upon and appropriate techniques with regard to environmental management more so wastewater management identified so as to be used in realizing sustainable and efficient wastewater management. Level of Involvement Government involvement is essential in implementation of most of wastewater management initiatives as well as private sectors and community as a whole. For instance the selection and construction of the appropriate technologies is generally initiated and financed, at least, partially by the government with the subsequent operation and maintenance of the facility should be responsibility of the local community therefore those employed should be people from that neighbourhood. This will help in reduction of surface water degradation which affects the availability of fresh water sources. In addition, government should ensure that the emerging policies incorporates wastewater management as a component of environmental management

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