EAUX NON CONVENTIONNELLES: UN RISQUE OU UNE SOLUTION AUX PROBLEMES D’EAU POUR LES CLASSES PAUVRES

 

RESUME

L’article s’intéresse aux qualités des eaux non conventionnelles et leurs effets sur la santé des consommateurs dans sept (07) quartiers dépourvus du réseau d’eau conventionnelle dans la ville de Mbouda, l’Ouest Cameroun.

Les techniques d’enquêtes sociologiques ont été utilisées pour obtenir l’information sur les sources d’approvisionnement en eau, les types de maladies hydriques existants dans les ménages, la nature de l’hygiène et l’assainissement accordé à ces points d’eau, ainsi que les traitements fournis à ces eaux de boissons avant la consommation.

Ensuite, une enquête a été effectuée dans les hôpitaux de la ville pour relever le nombre de cas des différentes maladies hydriques
enregistrées de janvier 2012 à février 2013.

Les échantillons d’eau ont été collectés sur 4 puits, 4 sources et 2 forages et analysés en décembre 2012 et en mars 2013, en utilisant la technique de dénombrement des germes sur milieu liquide et sur milieu solide.

Il ressort de cette étude que les eaux sont fortement contaminées par les microorganismes pathogènes; notamment les Streptocoques
fécaux, les Salmonelles, les Coliformes fécaux et les Protéus sp.

La consommation de ces eaux expose les populations à des risques sanitaires graves, nécessitant de ce fait un traitement approprié avant la consommation.

Mots clés: Eaux non conventionnelles, microorganismes pathogènes, assainissement, risques sanitaires

 

ABSTRACT

This paper looks at the quality of non-conventional waters and their effects on the health of consumers in seven (07) quarters deprived of conventional water network in Mbouda, West Cameroon.

Sociological techniques were used to obtain data on water sources, existing types of waterborne diseases in households, the nature of hygiene and sanitation of the water points and the treatment provided to these drinks water before consumption.

The number of cases of various waterborne diseases recorded in hospitals in the town from January 2012 to February 2013 was also verified. Water samples were collected from 4 wells, 4 springs and 2 boreholes in December 2012 and March 2013 for analyzes using the techniques of counting bacteria on liquid and solid medium.

Results of this study shows that water from non-conventional sources are contains high levels of pathogenic microorganisms, such as fecal streptococci, Salmonella, fecal coliforms and Proteus sp.

The consumption of these waters exposes consumers to serious health risks, thus requiring appropriate treatment before consumption.

Keywords: non-conventional water, pathogenic microorganisms, sanitation, health risks

Water Availability, Quality And Treatment Methods In Malawi: A Review

 

Abstract- Water is essential in all aspects of life such as health, economic growth, food production and support for the environment.

Water is scarce mainly in developing countries and pollution of the water resources is a major challenge contributed by the discharge of
wastewater from industries and municipal, agriculture runoff, household wastes and others.

The mainly used water resources in African countries are Lakes, boreholes, rivers, shallow wells, streams and springs.

People consume water from unprotected sources without treatment leading to an outbreak of waterborne diseases.

The water resources recorded high pollution levels with contaminants concentrations above the acceptable limits by the Malawi Bureau of Standards (MBS) and World Health Organization (WHO) for drinking water.

Parameters such as turbidity, Faecal coliforms and bacteria counts in the shallow wells for the sampled and analyzed water recorded a high-value range above the permissible limits for drinking water.

The drinking water treatment methods used are disinfection, filtration and boiling by a large percentage of pollution at the household level.

Total dissolved solids, electrical conductivity and nitrates in the analysis done for the water from the wells and boreholes were within the allowable for drinking water standards.

The TSS in another study analyzed for the drinking water recorded value above the WHO and MBS standards caused by the direct discharge
of the wastewater to water bodies.

The water treatment plants treat surface water and groundwater recorded raw water quality of some of the parameters within the allowable limits with and exemption of Liwonde water treatment plant recorded high turbidity water above drinking water standards.

Water treatment plants also recorded better removal of the pollutants in the water through coagulation, flocculation, sedimentation, filtration and disinfection processes.

The water quality index (WQI) as a key method for regulating water quality for domestic use and the overall effects of quality of water parameters that pose risk to water usage.

The WQI provides valuable information to water resource managers for it is efficiently reliable and useful method for communicating and evaluating the overall quality water information.

In terms of total hardness, the water quality was rated as mild hard to very hard water, while in salinity the water recorded high concentration of total dissolved solids and electric conductivity.

Therefore, this review paper, determined the water resources, water quality, and the treatment techniques for the drinking water, hence a cost-effective, feasible and affordable water treatment method is suggested for the water treatment plant in the treatment of the drinking water.

Index Terms- Drinking water, Water resources, Water treatment, Water Quality Index, Drinking water standards

Groundwater Quality: Mali

 

This is one of a series of information sheets prepared for each country in which WaterAid works.

The sheets aim to identify inorganic constituents of significant risk to health that may occur in groundwater in the country in question.

The purpose of the sheets is to provide guidance to WaterAid Country Office staff on targeting efforts on water quality testing and to encourage further thinking in the organisation on water quality issues.

 

Qualité physico-chimique et bactériologique des eaux souterraines et risques sanitaires dans quelques quartiers de Yaoundé VII, Cameroun

 

Au Cameroun, l’accès aux systèmes d’alimentation en eau potable en milieu urbain apparaît sélectif.

Les populations des quartiers situés en périphérie ont recours aux puits et sources pour assouvir leurs besoins.

La présente étude a pour objectif d’évaluer la qualité physico-chimique et bactériologique des eaux souterraines couramment utilisées dans quelques quartiers de l’arrondissement de Yaoundé VII. 24 échantillons d’eaux prélevés dans 6 sources (S1 à S6) et 2 puits (W1 et W2) ont été analysés suivant des méthodes normalisées.

Les températures relevées, proches de celle de l’air, révèlent le caractère libre des nappes étudiées.

Celles-ci subiraient l’influence directe des eaux d’infiltration. Les stations S1, W1 et W2 présentent des valeurs en nitrates supérieures à 50 mg/l (norme OMS).

La consommation de leurs eaux expose la population jeune à la méthémoglobinémie.

Contrairement aux recommandations de la norme camerounaise, les indicateurs de pollution fécale et les bactéries du genre Salmonella, ont été isolées dans les eaux analysées.

Une analyse en composante principale ainsi qu’un dendrogramme ont permis de classer les points d’échantillonnage, selon l’ordre croissant de pollution organique suivant : {S6}, (S3, S4, S5), (S1, S2), {W1}, {W2}.

Cependant, du point de vue pathogénique, S6, S3, S4, S5 sont les plus à craindre

 

Mots clés : Qualité des eaux, puits, sources, Yaoundé, risques sanitaires.

 

ABSTRACT

In Cameroon, access to drinking water supply systems in urban areas appears to be selective.

The populations located in the peripheral zone use wells and springs to satisfy their needs.

This study aims to assess the physico-chemical and bacteriological quality of the groundwater commonly used in some districts of Yaoundé VII. 24 water samples taken from 6 sources (S1 to S6) and 2 wells (W1 and W2) were analyzed according to standardized methods.

The temperatures recorded, close to that of the air, reveal the free nature of the aquifers studied which are directly influenced by the infiltration waters. Samples points S1, W1 and W2 presented concentration of nitrate above 50 mg/l (WHO standard).

The consumption of their waters exposes young people to methemoglobinemia.

On contrary to the recommendations of the cameroonian standard, the indicators of faecal pollution and bacteria of the genus Salmonella, were isolated in the waters analyzed.

A principal component analysis as well as a dendrogram permit to classify the sampling points, according to the
following increasing order of organic pollution: {S6}, (S3, S4, S5), (S1, S2), {W1}, {W2}. However, from a pathogenic point of view, S6, S3, S4, S5, are the most to be feared.

 

Keywords: Water quality, Dug wells, spring, Yaoundé, sanitary risks