2 resultados para Quality of the Water
em DRUM (Digital Repository at the University of Maryland)
Resumo:
Several Cronobacter outbreaks have implicated contaminated drinking water. This study assessed the impact of granular activated carbon (GAC) on the microbial quality of the water produced. A simulated water filter system was installed by filling plastic columns with sterile GAC, followed by sterile water with a dilute nutrient flowing through the column at a steady rate. Carbon columns were inoculated with Cronobacter on the surface, and the effluent monitored for Cronobacter levels. During a second phase, commercial faucet filters were distributed to households for 4-month use. Used filters were backwashed with sterile peptone water, and analyzed for Cronobacter, total aerobic plate count, coliform bacteria and Enterobacteriaceae. Cronobacter colonized the simulated GAC and grew when provided minimal levels of nutrients. Backwashed used filters used in home settings yielded presumptive Escherichia coli, Pseudomonas and other waterborne bacteria. Presumptive Cronobacter strains were identified as negative through biochemical and genetic test.
Resumo:
Over the past 15 years, the number of international development projects aimed at combating global poverty has increased significantly. Within the water and sanitation sector however, and despite heightened global attention and an increase in the number of infrastructure projects, over 800 million people remain without access to appropriate water and sanitation facilities. The majority of donor aid in the water supply and sanitation sector of developing countries is delivered through standalone projects. The quality of projects at the design and preparation stage is a critical determinant in meeting project objectives. The quality of projects at early stage of design, widely referred to as quality at entry (QAE), however remains unquantified and largely subjective. This research argues that water and sanitation infrastructure projects in the developing world tend to be designed in the absence of a specific set of actions that ensure high QAE, and consequently have relatively high rates of failure. This research analyzes 32 cases of water and sanitation infrastructure projects implemented with partial or full World Bank financing globally from 2000 – 2010. The research uses categorical data analysis, regression analysis and descriptive analysis to examine perceived linkages between project QAE and project development outcomes and determines which upstream project design factors are likely to impact the QAE of international development projects in water supply and sanitation. The research proposes a number of specific design stage actions that can be incorporated into the formal review process of water and sanitation projects financed by the World Bank or other international development partners.