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Cities in the developing world face the challenge of safe management of faecal sludge because of rapid population growth that overwhelms the sanitation infrastructure and services. In developing countries, only 50% of faecal sludge (FS) generated is safely managed the remaining portion is haphazardly disposed of in the environment risking public health and environment. In response to the urgent need for safely managed sanitation services, technological options for containment, desludging and transportation of FS are being modified. This paper reviewed current desludging practices and the potential of modified technological options for addressing FSM at containment, desludging, and transportation in Dar es Salaam unplanned urban settlements. The paper reviewed; water seal squat pan, Urine Diversion Dry Toilet (UDDT), split slabs, pre-installed suction hose, and the container-based sanitation (CBS) for containment stage. Others are the hand tools, sludge digger, the excrevator, rammer, and the eVac for desludging; and small pick-up truck and motorized tricycle and transfer stations for transfer and transportation of FS. Based on technical feasibility, social and environmental context of Dar es Salaam, the reviewed modified technology options have the potential of addressing FSM challenges in unplanned urban settlements in Dar es Salaam. However, institutional arrangement particularly the absence of the modified technologies in the menu of recommended technological options affects their upscaling. Paradoxically, most of the technologies have not been vigorously tried in the field to inform policy choice. Improvement of FSM with the application of modified technological options will require improvement in enabling environment for their operation and continuous modification. The major research gaps have also been identified in this review. Keywords : Containment, Desludging, Faecal Sludge Management, Modified technology options Non-sewered sanitation.

Worldwide, every day human beings generate millions of tons of Faecal Sludge (FS), which is rich in water, nutrients, energy, and organic compounds. Yet FS is not being managed in a way that permits us to derive value from its reuse, while at the same time, millions of farmers struggle with depleted soils and lack of water. In most of the developing countries, energy for cooking is mainly derived from cutting of trees, either as wood or charcoal. Resource recovery and reuse from FS can create livelihoods, enhance food security, support green economies, reduce waste and contribute to cost recovery in the sanitation chain. Many studies have reported on the different technologies used for FS treatment, such as dewatering and bio-stabilization. The commonly used dewatering technology is sand drying bed, which occupied a large space and has a low dewatering rate. To enhance the dewatering rate of FS as well as reducing the size of the sand drying bed, the use of chemical conditioners has been done. Despite the fact that they have been used successfully, chemical conditioners are expensive, have health and environmentally hazardous. In recent years, attempts have been made to use local conditioners to tackle the drawbacks experienced from chemical conditioners. Although the feasibility of applying local conditioners for FS dewatering has been studied, its potentials on FS treatment have not been well documented. This review indicates that there is potential for local conditioners linked with dewatering, enhancing of FS resources recovery and in reducing costs of operating and maintaining FS treatment plant. Moreover, local conditioners have the potential in contribution to socio-economic development in Tanzania through renewable energy production, income generation and food- health security, soil and water conservation, eco-sanitation and reduction of environmental degradation. Keywords : Faecal sludge, Local conditioners, Resource recovery, Sanitation, Treatment.

The use of High Rate Algal Ponds (HRAPs) for the treatment of wastewater and resource recovery has raised interest in recent years. Treatment of wastewater through this technology has proved to have high efficiency in reducing the level of pollution, nutrients, dissolved solids as well as pathogens. HRAPs are more efficient than conventional Wastewater Stabilization Ponds (WSPs) due to their design approach that provides room for high rate bio-chemical processes, which increase the mechanisms of nutrients and pathogens removal as well as the rate of micro-algae production for purposes of resource recovery. This paper reviews the upgrading potential of existing WSPs to HRAPs for resource recovery from products of wastewater for biofuel production, as a plant nutrient or for irrigation purposes and animal feeding. Several results have reported HRAPs to have efficiency in reducing bacterial contamination in excess of 99% while the removal of organic matter of up to 84% for Chemical Oxygen Demand (COD) and 88% for Biochemical Oxygen Demand under normal conditions have been reported. The removal for nitrogen was indicated to vary from 50 t0 98% while that of phosphorus varies from 32 to 99% depending on the culture conditions. It was further noted that, the potential for resource recovery from HRAPs is high in terms of energy and nutrients recovered through algae biomass, particularly for biofuel and animal feed production. Whereas among the dominant algal species of the HRAP Chlorella vulgaris revealed to have suitability in both treatment of wastewater and achieved a higher effluent quality and having nutrients contents essential for lipid extraction for biofuel and as a protein source for animal feeding which is largely attributed by their ability to grow very rapidly and to tolerate varieties of cultural conditions. To date, limited research attention has been given to studying the re-use potential of wastewater for irrigation purposes in Africa. Keywords : High rate algal ponds, Wastewater Treatment, Micro-algae, Resource Recovery.

In this work, a conceptual framework for faecal sludge (FS) management and resource recovery in Dar es Salaam city was developed. Material Flow Analysis (MFA) approach was used to assess and quantify the current materials and nutrients to support on decisions for nutrient recovery and minimize environmental pollution in three unplanned settlements of Manzese, Keko and Kipawa in Dar es Salaam city. Nitrogen and Phosphorus were chosen as indicators for the evaluation of the process. The results showed that about 75% of the Dar es Salaam city population relies on pit latrines and 15% connected to septic tanks, translating to a large amount of faecal sludge being contained onsite. The situational analysis study on faecal sludge management (FSM) showed that the collection, treatment and proper disposal of FS are the major challenges that pose risks to public health. Currently, 57% of faecal sludge generated in Dar es Salaam is disposed to the environment inappropriately. Onsite Sanitation Systems in all study areas are the main polluters, discharging large quantity of nutrients to the environment. About 37.7% of faecal sludge is with large amount of nutrients emptied from onsite sanitation systems discharged to the environment and through seepage to the groundwater. Keywords : Faecal sludge; Material flow analysis; Resource recovery; unplanned settlements.