User acceptance: the key to evaluating SODIS and other methods for household water treatment and safe storage

Household water treatment has been identified as one effective strategy to interrupt transmission routes of diarrhoea causing pathogens, and thus to mitigate the global burden of waterborne diseases. And yet, the commitment of governments and international organizations to integrate household water treatment and safe storage (HWTS) into their water supply, sanitation, and hygiene promotion programmes remains limited. More efforts are required to scale up the initial successes in the promotion of HWTS methods, and to achieve sustainable application at user level. This article illustrates the experience with the promotion of one particular HWTS approach solar water disinfection (SODIS) as an input to the debate on effectiveness, user acceptance, and integrated planning in the context of HWTS approaches

Water treatment in Northern Ghana

Water treatment in Northern Ghan

Potable water for all: promotion of solar water disinfection

Potable water for all: promotion of solar water disinfectio

Progress in solar water disinfection (SODIS)

Progress in solar water disinfection (SODIS

SORAS - a simple arsenic removal process

The serious threat to the health of millions of people through consumption of arsenic-rich groundwater in Bangladesh calls for immediate action on various levels. One of these actions is be the development of a low-cost and simple arsenic removal method available to every household. The development of alternative water sources and/or the installation of larger arsenic removal units will take more time due to logistic and financial constraints. Currently existing small-scale arsenic removal procedures require chemicals that are either not easily available and/or affect water taste and odour. Solar oxidation and removal of arsenic (SORAS) is a simple method that uses irradiation of water with sunlight in PET- or other UV-A transparent bottles to reduce arsenic levels from drinking water. The SORAS method is based on photochemical oxidation of As(III) followed by precipitation or filtration of As(V) adsorbed on Fe(III)oxides as shown in Fig. 1. Groundwater in Bangladesh naturally contains Fe(II) and Fe(III) and therefore, SORAS could reduce arsenic contents and would be available to everyone at virtually no cost. It could be a water treatment method used at household level to treat small quantities of drinking water

SODIS - an arsenic mitigation option?

About 95% of the population in Bangladesh is supplied by groundwater from five million wells. Several survey programmes revealed that arsenic might be found in three million wells affecting up to 70 million people. Currently, alternative water resources and water treatment processes for the arsenic removal are being developed. One considered option is to return from the groundwater to surface water which, however, in most cases is not safe for consumption and, therefore, requires disinfection. SODIS (Solar Water Disinfection) is a simple and lowcost water treatment method to improve the microbiological quality of drinking water at household level. PET plastic bottles are filled with polluted water and exposed to sunlight for 1 day. The microorgansisms are inactivated by the UV-A radiation and the increased water temperature. SODIS applied world-wide is described in www.sodis.ch and has been field tested in Bangladesh to study its effciency and socio-cultural acceptance