A comparative assessment of communal water supply and self supply models for sustainable rural water supplies: a case study of Luapula, Zambia

Over the last couple of decades, a significant amount of research has been carried out on rural water supplies in developing countries, and have identified the fact that the communal water supply model is not sustainable everywhere, especially in sparsely populated rural areas; factors obstructing sustainability include lack of spare parts, management systems and private/public capacity. Despite their enormous contribution to the water sector, the extant studies stay within the subsidized communal water supply and capacity building, post construction support or management system. In other words, very few studies have been done into household (private) level water supply. The Self Supply model is an approach which provides support to households/communities to complement their efforts and accelerate sustainable access to safe water incrementally through improvement to traditional water sources (hand dug wells) by putting in their own investment. The Self Supply model may give significant benefits for sustainable safe water supplies, especially in sparsely populated rural areas, in comparison with the communal water supply though to date there has been little monitoring and systematic analysis of what impact these changes have made at the grassroots level. The standpoint of this study is pragmatic, and herein, mixing quantitative and qualitative methods was justified in order to design the research methodologies. The research was conducted in the Luapula Province of Zambia using a concurrent triangulation strategy to offset the weakness inherent within one method with the strengths of the other. The data was collected through inventory and sanitary surveys, water quality testing, household surveys, document analyses, focus group discussions and key informant interviews to determine the most appropriate water supply model for safe, accessible, sustainable, cost-effective and acceptable water supplies for households in sparsely populated rural areas of Zambia. The principal argument of this study is that reliance only on a communal water supply model limits the achievement of increased sustainable access to a safe water supply; hence a Self Supply model is needed which does not compete with the communal models but works alongside them in sparsely populated rural areas of developing countries for the purpose of increasing access and achieving sustainability. It was strongly defended by the overall findings that a Self Supply model could significantly reduce the faecal contamination risk in water quality and deliver a higher per capita water use and better convenience of access than the communal model; however its reliability with respect to the water source drying up needs to be monitored. Further, this does not mean that the communal model is not sustainable anywhere, rather that it is important to build blocks for a sustainable environment to access safe water in a symbiotic way between the communal and Self Supply models under the condition that the government and NGOs/external support agencies overcome the temptation to provide a water supply to rural dwellers as a giveaway social service

Improving access to safe water for internally displaced persons (IDPs) in a fragile state, Somalia

Delivering basic social service to most vulnerable people in fragile states is the ultimate challenge for both the international community and government institutions. Water service delivery is an inevitable necessity for human lives. Provision of water supply at Internally Displaced Persons (IDP) settlements has been implemented in several areas of Somalia in order to tackle with mobile populations, which consisted of majority of the population. Findings revealed that potable small scale water treatment systems using surface water were effective in a context of high population mobility. New flocculation technology, Poly-Glu, made by soy-bean in combination with chlorination worked well in the high turbidity water where only turbid surface water is available. Yet to address long-term sustainability, involvement of the private sector and capacity building initiatives are needed to maintain small-scale water treatment systems utilizing this new treatment method without external support

Self-supply: bridging the gap between household demand and community water supply?

This paper discusses rural water supply at grassroots level, and challenges the assumption that a community water supply facility is the only solution for rural water supply, especially in sparsely populated areas. A comparison is made between two water service models from case studies in Zambia: those with conventional communal water supplies and Self Supply models. Findings revealed that a Self Supply service could significantly reduce faecal contamination risk in water quality and deliver higher per capita water use and better convenience of access than conventional supply, yet its reliability regarding water source dry up requires to be monitored. A conventional community-based water service may not fulfil the households’ demand due to the nature of community ownership and the distance from household to a community water facility. Since the underlying service delivery models are different, an integrated approach is required for a rural water supply strategy and national policy

Laboratory Verification of a Proposed New Method to Determine the In-Situ Effective Porosity of Unsaturated Soil

A laboratory validation of a proposed new method of determining the in-situ effective porosity of unsaturated soils was carried out on unsaturated river sand. The proposed method consists of boring a small diameter hole into the soil and inserting an Amplitude Domain Reflectometry (ADR) probe at the bottom part of the hole. Water is supplied into the hole till saturation and later de-saturated. The water content with time is determined from the ADR probe voltage potential readings. The effective porosity is determined from the difference between the saturated and de-saturated water contents. However, in the laboratory, the water is supplied through the top and bottom parts of the sample. From the experiments the obtained effective porosity ranged from 0.28 to 0.29 for wetting from the top with an average of 0.287 and 0.29 to 0.30 for wetting from the bottom with an average of 0.293. The determined effective porosity ranged from 71.7-73.3% of the real initial porosity of 0.40 of the river sand. The maximum attained degree of saturation during the experiment was 91%. The results indicated that the method will be suitable and useful in determining the effective porosity of medium grained unsaturated soils

State of the Art on Filter Design and Particle Clogging; and Proposed New Numerical Approach to Redesign

Filters are essential in the design of embankments/dams, drains and wells for water and oil supplies. As a result of these functions, filter use is increasing. In order to use the required filter, various empirical relations have been given based on mathematical and field experience. However, these guidelines have not worked to perfection considering the fact that clogging within the filter face is a serious challenge. A short review on filter design criteria is given in this script coupled with a numerical formulation to propose the design limits

Laboratory Verification of a Proposed New Method to Determine the In-Situ Effective Porosity of Unsaturated Soil

A laboratory validation of a proposed new method of determining the in-situ effective porosity of unsaturated soils was carried out on unsaturated river sand. The proposed method consists of boring a small diameter hole into the soil and inserting an Amplitude Domain Reflectometry (ADR) probe at the bottom part of the hole. Water is supplied into the hole till saturation and later de-saturated. The water content with time is determined from the ADR probe voltage potential readings. The effective porosity is determined from the difference between the saturated and de-saturated water contents. However, in the laboratory, the water is supplied through the top and bottom parts of the sample. From the experiment the obtained effective porosity ranged from 0.28 to 0.29 for wetting from the top with an average of 0.287 and 0.29 to 0.30 for wetting from the bottom with an average of 0.293. The determined effective porosity ranged from 71.7-73.3 % of the real initial porosity of 0.40 of the river sand. The maximum attained degree of saturation during the experiment was 91 %. The results indicated that the method will be suitable and useful in determining the effective porosity of medium grained unsaturated soils