STUDY OF PHYSICOCHEMICAL AND MICROBIOLOGICAL QUALITY OF THE SPRING WATERS OF THE REGION OF OUM TEBOUL WILAYA OF EL TARF- ALGERIA

The present work aims to assess the physico-chemical and microbiological parameters of the waters of the three sources (Ain Bergougaya, Ain Sigleb and Siporex) in the region of Oum el Teboul wilaya of El Tarf. Parameters such as temperature, pH, conductivity and salinity were measured in situ with a field multimeter. Hardness (62 mg/L to 266 mg/L), salinity (0.01 to 1 mg/L). From a microbiological point of view, there has been no evidence of the complete absence of germs of contamination such as total coliforms and fecal coliforms. This study compared to the drinking water standards shows that the waters in the area studied are of good quality.

Removal and growth of microorganisms across treatment and simulated distribution at a pilot-scale direct potable reuse facility

Multi-barrier advanced treatment trains are able to purify wastewater to drinking water standards, but improved methods are needed to better understand microbial concentrations, viability, and growth potential throughout treatment and distribution.

Achieving Economically Feasible Drinking Water Regulation

United States Environmental Protection Agency (USEPA) has regulated drinking water since the 1974 Safe Drinking Water Act (SDWA). Congress directed it to achieve three conflicting goals: (i) establish stringent nationwide standards, (ii) ensure that these standards are both technologically and economically feasible, and (iii) accommodate significant differences in cost among water systems of different sizes with different water sources. USEPA chose to emphasize goal (i) at the expense of (ii) and (iii). In 1986, Congress intensified its preference for (i), was silent concerning goal (ii), and criticized USEPA for failing to achieve goal (iii). In lieu of economic feasibility, the Agency substituted “affordability,” defined as expenditures up to 2.5 % of national median household income irrespective of the benefits. This imposed deadweight losses, and substantial inequities on rural areas, low-income communities, and low-income households generally. In 1996, Congress directed USEPA to use benefit-cost analysis positively and normatively. Regulations issued since 1996 do not appear to comply, however. A review of post-1996 drinking water standards indicates that most were certified by USEPA as having benefits that justified costs, but these determinations were unsupported by the Agency’s own regulatory impact analyses. This article proposes that USEPA define by regulation that “economic feasibility” means marginal benefits exceed marginal costs for the smallest water system subject to SDWA, and that all future drinking water standards must be economically feasible. Economic efficiency would be greatly enhanced and the pervasive inequities of “affordability” greatly diminished. Unlike “affordability,” this definition is objective and compatible with lay intuition about the meaning of key regulatory terms.

Nano-spatially confined Pd–Cu bimetals in porous N-doped carbon as an electrocatalyst for selective denitrification

Nanodenitrification is achieved by bimetallic Pd–Cu nanoparticles encapsulated in porous N-doped carbon as electrocatalysts, with reduced nitrate below drinking water standards and a N2 selectivity as high as 83% in a neutral electrolyte.

Water quality and microbial contamination status of Madawachchiya, Padaviya and Kebithigollewa areas in Anuradhapura District, Sri Lanka

Typhoid or enteric fever is a worldwide infection caused by the bacterium Salmonella enterica. In Sri Lanka, 12,823 Salmonella positive cases were recorded and 133 cases were recorded from Anuradhapura district during 2005 to 2014. Therefore, the study was carried out to identify the microbiological and chemical contamination status of forty-four water sources in Anuradhapura area during October 2016. The study was focused to determine total coliform, faecal coliform, Salmonella spp. and Shigella spp. contamination along with some physico-chemical parameters of both ground and surface water. Sampling, transportation, and analysis were performed following standard protocols. Results of the study revealed that almost all sampling locations were contaminated with both total and E. coli bacteria and the values were not within the World Health Organization and Sri Lanka Standards drinking water quality standards. Around 32% of sampling locations were positive for Salmonella spp. and among them, 2 spring sampling locations are being highly used to extract water for drinking. However, Shigella spp. was not recorded during the study period. Majority of the sampling points were not within the Sri Lanka drinking water standards for COD and 25% sampling locations were recorded greater than 750 μS∙cm−1 conductivity. Also, 55% of locations recorded very hard water where the highest values were recorded in Padaviya. The tested other water quality parameters: NO2-N, NH3-N, and total phosphate (TP) concentrations were found within the Sri Lanka drinking water standards. PCA analysis revealed that sampling locations were grouped into three groups such as; well water, tank water and springs.

Assessment of Bacteriological and Physicochemical Quality of Drinking Water from Source to Household Tap Connection in Nekemte, Oromia, Ethiopia

In Ethiopia, access to improved water supply and sanitation has been very low and hence majority of the communicable diseases are associated with unsafe and inadequate water supply. Thus, the aim of this study was to assess physicochemical and bacteriological characteristics of water from sources to household connection in Nekemte town. A cross-sectional study was conducted from November 2015 to March 2016. Water samples were collected in triplicates from selected 30 sampling points from source, disinfection point, main distribution system tank, and household taps. All samples were analysed for bacteriological, chemical, and physical quality parameters using standard procedures. The results showed that temperature, pH, turbidity, total dissolved substances, and electrical conductivity of the water samples were varied between 16.9 and 22°C, 6.8–7.0, nil-12 NTU, 50–70 mg/l, and 40–46 µS/cm, respectively. Phosphate and nitrate concentrations of the water samples also ranged between 0.65 and 1 mg/l and 2.2–6.5 mg/l, respectively. Free residual chlorine concentration in the majority of the water samples was less than 0.5 mg/l. All samples were positive for total coliform with counts ranging from 12 to 120 CFU/100 ml, whereas faecal coliforms were detected in only 37% of tap water samples. In general, the majority of the tested parameters were within the permissible range of both the WHO and Ethiopian drinking water standards. However, Fe, Mn, faecal coliforms, total coliforms, and temperature did not conform to both WHO and Ethiopian drinking water standards. Based on the results, we can conclude that water quality deterioration was both at the sources and in the supply networks. Hence, proper drainage, sewage disposal systems, and sufficient disinfection of water with chlorine are of prime importance to deliver safe drinking water to the residents of Nekemte town.