Tag Archives: water supply

Assessment of the Municipal Water Cycle in China

Tao Wang, Shuming Liu, Xuepeng Qian, Toshiyuki Shimizu, Sébastien M.R. Dente, Seiji Hashimoto, Jun Nakajima. Assessment of the municipal water cycle in China. Science of The Total Environment Volumes 607–608, 31 December 2017, Pages 761-770.

Water produced from municipal utilities accounts for nearly 10% of the sum water demand in China. The municipal water cycle that integrates processes of urban water supply, water use, sewage treatment, and water reclamation has been assessed for 655 cities across nine drainage areas in mainland China in 2012. These cities in total extracted 55 km3 raw water for municipal use from surface waterbodies and ground aquifers, approximate to the countrywide freshwater extraction of Russia or Italy. After purification and transmission, 45 km3 water was distributed to industrial, service, and domestic users. 36 km3 of post-use sewage was collected and environmentally safely treated; merely 3.2 km3 of the treated water was reclaimed. Driven by increasing urbanization, the municipal water demand in cities of China may grow 70% by 2030. The Hai River and the Huai River basins, which harbor 137 cities and occupy a majority of the densely populated North China Plain, are most exposed to physical water scarcity. The municipal water abstraction in these cities can remain constant by promoting demand-side and process conservation in the next two decades. Interbasin transfer and unconventional sources will provide municipal water double than the cities’ need. Whereas the urban water security can be technically enhanced, the challenges are to better improve water use efficiency and mitigate economic and environmental costs of the municipal system.

Fecal Contamination Pollutes Drinking Water Sources, Kenya

Okullo JO, Moturi WN, Ogendi GM. Open Defaecation and Its Effects on the Bacteriological Quality of Drinking Water Sources in Isiolo County, Kenya. Environ Health Insights. 2017 Oct 9;11:1178630217735539. doi: 10.1177/1178630217735539.

BACKGROUND INFORMATION: The post-2015 Sustainable Development Goals for sanitation call for universal access to adequate and equitable sanitation and an end to open defaecation by 2030. In Isiolo County, a semi-arid region lying in the northern part of Kenya, poor sanitation and water shortage remain a major problem facing the rural communities.

OBJECTIVE: The overall aim of the study was to assess the relationship between sanitation practices and the bacteriological quality of drinking water sources. The study also assessed the risk factors contributing to open defaecation in the rural environments of the study area.

METHODS: A cross-sectional study of 150 households was conducted to assess the faecal disposal practices in open defaecation free (ODF) and open defaecation not free (ODNF) areas. Sanitary surveys and bacteriological analyses were conducted for selected community water sources to identify faecal pollution sources, contamination pathways, and contributory factors. Analysis of data was performed using SPSS (descriptive and inferential statistics at α = .05 level of significance).

RESULTS: Open defaecation habit was reported in 51% of the study households in ODNF villages and in 17% households in ODF villages. Higher mean colony counts were recorded for water samples from ODNF areas 2.0, 7.8, 5.3, and 7.0 (×103) colony-forming units (CFUs)/100 mL compared with those of ODF 1.8, 6.4, 3.5, and 6.1 (×103) areas for Escherichia coli, faecal streptococci, Salmonella typhi, and total coliform, respectively. Correlation tests revealed a significant relationship between sanitary surveys and contamination of water sources (P = .002).

CONCLUSIONS: The water sources exhibited high levels of contamination with microbial pathogens attributed to poor sanitation. Practising safe faecal disposal in particular is recommended as this will considerably reverse the situation and thus lead to improved human health.

Bromide in Drinking Water Sources, Pennsylvania

Good KD, Vanbriesen JM. Power plant bromide discharges and downstream drinking water systems in Pennsylvania. Environmental science and technology. 2017 Sep 25. doi: 10.1021/acs.est.7b03003.

Coal-fired power plants operating wet flue gas desulfurization (FGD) have recently been implicated in increasing bromide levels in drinking water sources, which affect formation of disinfection by-products. Bromide was not included as a regulated constituent in the recent steam electric effluent limitations guidelines and standards (ELGs) since the U.S. EPA analysis suggested few drinking water facilities would be affected by bromide discharges from power plants. The present analysis uses a watershed approach to identify Pennsylvania drinking water intakes downstream of wet FGD discharges and considers the population served by these systems, providing context for the potential extent of the effects of coal-fired power plant discharges on downstream drinking water plants and consumers of publicly-supplied drinking water. Twenty-two (22) public drinking water systems serving 2.5 million people were identified as being downstream of at least one wet FGD discharge. During mean August flow conditions in receiving rivers, the median bromide concentration contributions at intake locations ranged from 5.2 to 62 µg/L for the Base scenario (including only natural bromide in coal) and 16 to 190 µg/L for the Bromide Addition scenario (natural plus added bromide for mercury control); ranges depend on bromide loads and receiving stream dilution capacity.

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A Model for Developing Water and Sanitation Capacity

Rainwater Harvesting in a Subarctic Community

Mercer N, Hanrahan M. Straight from the heavens into your bucket”: domestic rainwater harvesting as a measure to improve water security in a subarctic indigenous communityInternational journal of circumpolar health. 2017;76(1):1312223. doi: 10.1080/22423982.2017.1312223

BACKGROUND: Black Tickle-Domino is an extremely water-insecure remote Inuit community in the Canadian subarctic that lacks piped-water. Drinking water consumption in the community is less than a third of the Canadian national average. Water insecurity in the community contributes to adverse health, economic, and social effects and requires urgent action.

OBJECTIVES: To test the ability of domestic rainwater harvesting (DRWH) for the first time in the subarctic with the goal of improving water access and use in the community.

DESIGN: This project utilised quantitative weekly reporting of water collection and use, as well as focus group discussions. DRWH units were installed at seven water-insecure households chosen by the local government. Results were measured over a 6-week period in 2016.

RESULTS: Participants harvested 19.07 gallons of rainwater per week. General purpose water consumption increased by 17% and water retrieval efforts declined by 40.92%. Households saved $12.70 CDN per week. Participants reported perceived improvements to psychological health. Because no potable water was collected, drinking water consumption did not increase. The study identified additional water-insecurity impacts.

CONCLUSION: DRWH cannot supply drinking water without proper treatment and filtration; however, it can be a partial remedy to water insecurity in the subarctic. DRWH is appropriately scaled, inexpensive, and participants identified several significant benefits.

California Drought Moves Through the Central Valley

“The U.S. Bureau of Land Management has allocated100 percent water deliveries to Central Valley water districts for the first time in a decade, as the 80-degree weather this weekend causes risk of rapid snowmelt flooding.” click here

Brackish Groundwater in the United States a Viable Water Supply

Stanton, J.S., Anning, D.W., Brown, C.J., Moore, R.B., McGuire, V.L., Qi, S.L., Harris, A.C., Dennehy, K.F., McMahon, P.B., Degnan, J.R., and Böhlke, J.K., 2017, Brackish groundwater in the United States: U.S. Geological Survey Professional Paper 1833, 185 p., https://doi.org/10.3133/pp1833.

For some parts of the Nation, large-scale development of groundwater has caused decreases in the amount of groundwater that is present in aquifer storage and that discharges to surface-water bodies. Water supply in some areas, particularly in arid and semiarid regions, is not adequate to meet demand, and severe drought is affecting large parts of the United States. Future water demand is projected to heighten the current stress on groundwater resources. This combination of factors has led to concerns about the availability of freshwater to meet domestic, agricultural, industrial, mining, and environmental needs. To ensure the water security of the Nation, currently [2016] untapped water sources may need to be developed.

Brackish groundwater is an unconventional water source that may offer a partial solution to current and future water demands. In support of the national census of water resources, the U.S. Geological Survey completed the national brackish groundwater assessment to better understand the occurrence and characteristics of brackish groundwater in the United States as a potential water resource. Analyses completed as part of this assessment relied on previously collected data from multiple sources; no new data were collected. Compiled data included readily available information about groundwater chemistry, horizontal and vertical extents and hydrogeologic characteristics of principal aquifers (regionally extensive aquifers or aquifer systems that have the potential to be used as a source of potable water), and groundwater use. Although these data were obtained from a wide variety of sources, the compiled data are biased toward shallow and fresh groundwater resources; data representing groundwater that is at great depths and is saline were not as readily available.

One of the most important contributions of this assessment is the creation of a database containing chemical characteristics and aquifer information for the known areas with brackish groundwater in the United States. Previously published digital data relating to brackish groundwater resources were limited to a small number of State- and regional-level studies. Data sources for this assessment ranged from single publications to large datasets and from local studies to national assessments. Geochemical data included concentrations of dissolved solids, major ions, trace elements, nutrients, and radionuclides as well as physical properties of the water (pH, temperature, and specific conductance). Additionally, the database provides selected well information (location, yield, depth, and contributing aquifer) necessary for evaluating the water resource.

The assessment was divided into national-, regional-, and aquifer-scale analyses. National-scale analyses included evaluation of the three-dimensional distribution of observed dissolved-solids concentrations in groundwater, the three-dimensional probability of brackish groundwater occurrence, and the geochemical characteristics of saline (greater than or equal to 1,000 mg/L of dissolved solids) groundwater resources. Regional-scale analyses included a summary of the percentage of observed grid cell volume in the region that was occupied by brackish groundwater within the mixture of air, water, and rock for multiple depth intervals. Aquifer-scale analyses focused primarily on four regions that contained the largest amounts of observed brackish groundwater and included a generalized description of hydrogeologic characteristics from previously published work; the distribution of dissolved-solids concentrations; considerations for developing brackish groundwater resources, including a summary of other chemical characteristics that may limit the use of brackish groundwater and the ability of sampled wells producing brackish groundwater to yield useful amounts of water; and the amount of saline groundwater being used in 2010.