Effect of Radio-Frequency Treatment on the Changes of Dissolved Organic Matter in Rainwater

Rainwater is a potential source of drinking water, but has various components of dissolved organic matter (DOM). DOM is a reservoir of potential hazards in drinking water. Therefore, a new method is required to purify rainwater as a drinking water source in terms of DOM aspects. A radio-frequency (RF) treatment system is introduced here to purify source water with a small possibility of contamination. RF is generated by applying a frequency of 1.5 MHz through a glass reactor with a diameter of 2 mm which is wrapped by a 2 mm copper wire. The results demonstrate that UV260 value and dissolved organic carbon (DOC) are reduced during RF treatment. DOC was reduced by a lower amount compared to UV260, suggesting the partial transformation of bio-refractory DOM. A fluorescence excitation-emission matrix showed that humic-like substances in rainwater were reduced faster than protein-like ones, indicating that humic-like substances are susceptible to reduction by RF treatment. The results offer information on the use of RF treatment in a rainwater purification process for the production of drinking water.

Health Risk Assessment in Southern Carpathians Small Rural Communities Using Karst Springs as a Drinking Water Source

The chemical quality of waters from eight karst springs from the Southern Carpathians and the health risk of small rural communities using these springs as a drinking water source were assessed. The results indicated that the spring waters in the studied area are chemically suitable to be used as drinking water and pose no health risks for adults and children. The spring water can be generally described as having circumneutral pH, Ca-Mg-HCO3− facies, excellent to good palatability, and low trace metal and nitrate content. The variation of chemical parameters between spring and autumn was low. These springs could become appropriate drinking water sources for the neighboring rural communities after the assessment of their microbiological status and, if it is the case, proper water treatment. Moreover, periodic monitoring of the water’s chemical parameters, mostly nitrates, as well as the establishment of a protected area near the springs to prevent the negative impact of anthropogenic sources on water quality is recommended.

Effectiveness of combined upflow roughing filter and upflow slow sand filter to reduce turbidity in Citarum water as a source of drinking water

Turbidity of Citarum River was high, fluctuating and used as drinking water source by people and PDAM (Regional Drinking Water Company). The aim of this study was to determine the ability of upflow roughing filter (URF) and upflow slow sand filter (USSF) in reducing turbidity. It was called multistage filtration (MSF). MSF was varied with and without settler. Gravel diameters and perviousness as follows: 0.5 cm was 0.243, 1 cm: 0.264, 2 cm: 0.265, 5 cm: 0.302 or just 24 - 30% of total URF’s volume. When settler was run with surface loading 0.5 m3/m2/hour, flowrate 0.67 l/minute, turbidity 321.16 - 3,496.53 NTU, efficiency was 57.9 - 96.2%. Settler reduced turbidity significantly. URF1 enhanced turbidity removal. However, URF2, URF3, USSF were not effective. In experiment without settler, turbidity was 130.78 - 533.00 NTU but its reduction in URF1 was bad. But in URF2 turbidity was almost the same as in experiment with settler. Efficiency was 41.9 - 89.1%. Here URF1 and URF2’s function were almost the same as settler and URF1. URF3 was ineffective, can be removed. USSF was still needed even though only able to reach 10-25 NTU. URF and USSF contributed to higher efficiency of turbidity removal.

An innovative subterranean spring capture method for improved water quality

Many rural communities in Andean countries of South America rely on springs as their primary drinking water source. A variety of spring capture methods are employed resulting in varying water quality. Water from these spring-fed sources, delivered to the community via a distribution network, is often not chlorinated, increasing the risk of water-borne pathogens. A simple, improved technique has been developed in Ecuador's Chimborazo Province by a local Christian organization, Corporación de Desarrollo Integral Socio Económico (CODEINSE), to protect spring water sources for community water supply. This new technique, ‘the CODEINSE method’, builds on the strengths of traditional subterranean spring captures while employing several design improvements, like a concrete cap and sufficient gravel pack, to prevent surface water contamination. According to water quality data collected in Ecuador, the CODEINSE method consistently provides high-quality water with substantially reduced levels of water-borne pathogens compared to traditional spring capture methods. On average, the CODEINSE method yields water with less than 1.0 CFU/100 mL, water that is deemed no risk by the World Health Organization. The CODEINSE method has the potential to improve water quality not only in the rural Andean communities in Ecuador but also in developing countries across the world.

Hydrochemical Characteristics, Quality Assessment and Solute Source Identification of Coal Bearing Fractured Aquifer in Dingji Coal Mine, Huainan Coalfield, China

Coal-bearing fractured aquifer is regarded as one of the most dynamic mine water inrush sources, and after pumping and treating, it can be used as a water supply for coal mine production, coal preparation plant, rural irrigation, and even reserved drinking water source. Hence, this study focuses on the hydrochemical characteristics, ion source, and water quality evaluation with respect to drinking and irrigation of the coal-bearing fractured aquifer in Dingji coal mine, Huainan coalfield, China. Descriptive statistics and hydrochemical classification diagrams including the Piper diagram and Chadha rectangular diagram were carried out to depict the hydrochemical characteristics and facies. The water quality of the aquifer was assessed for irrigation and drinking purposes using the WHO threshold value, water quality index (WQI), SAR, % Na and RSC. Hydrochemical formation mechanism and solute origin of major ions were explained by Gibbs diagram, bivariate diagrams, and multivariate statistical analysis. The results show that the dominant hydrochemical facies are the Cl-Na type and the HCO3-Na type. The sequence of ions is Na+ > Ca2+ > Mg2+ for cations, and HCO3? > Cl- > SO42- > CO32- for anions. The main solute sources are controlled by various factors including the dissolution of halite, sulfate, and carbonate rocks, the weathering of silicate, and cation exchange. Water quality assessment based on WQI suggests that none of the samples fall under the excellent category, even 32.5% is not suitable for direct drinking. Meanwhile, the samples of the aquifer are generally unsuitable for irrigation. Before utilization for irrigation and even drinking, appropriate water treatment should be applied to guarantee its security during usage.

Identifying and Prioritizing Urban and Commercial Stormwater Concerns: City of Grants Pass, Oregon

For many communities, drinking water comes from surface water sources, or source water, such as rivers and creeks. Within the city of Grants Pass, Oregon, this is the case. The Rogue River, which spans 215 miles, beginning near Crater Lake and emptying into the ocean at Gold Beach, is Grants Pass’ drinking water source. While the capacity of the Rogue River, in relation to drinking water, is rarely an issue for the City of Grants Pass’ Public Works Department, the potential contaminant sources (PCS) from the urban, commercial, and industrial geographical areas of Grants Pass is a concern. In order to deploy treatment processes that are capable of targeting these PCS, it is important to have an idea of where and how these PCS are reaching the storm drains, creeks, and eventually the Rogue River. The purpose of this study was to identify area-specific risk components and how those components spatially aligned with PCS and their locations. Geographic Information System (GIS) analysis and a risk matrix were used to rank the PCS according to risk in relation to Grants Pass’ source water intake. PCS ranked as high priority, or exuding the highest risk to drinking water quality, were followed up with onthe- ground surveys. After surveying the high priority PCS, best management practices (BMP) recommendations were made to the City of Grants Pass to better protect the drinking water quality. Branching off of this initial project work came similar studies in many other Rogue Basin communities. With this continued work, improvements were made to streamline the processes, such as recording survey observations. Overall, this project work has led to many discoveries regarding threats to drinking water quality and how to best respond to certain types of threats.

Comparison of potential drinking water source contamination across one hundred U.S. cities

Drinking water supplies of cities are exposed to potential contamination arising from land use and other anthropogenic activities in local and distal source watersheds. Because water quality sampling surveys are often piecemeal, regionally inconsistent, and incomplete with respect to unregulated contaminants, the United States lacks a detailed comparison of potential source water contamination across all of its large cities. Here we combine national-scale geospatial datasets with hydrologic simulations to compute two metrics representing potential contamination of water supplies from point and nonpoint sources for over a hundred U.S. cities. We reveal enormous diversity in anthropogenic activities across watersheds with corresponding disparities in the potential contamination of drinking water supplies to cities. Approximately 5% of large cities rely on water that is composed primarily of runoff from non-pristine lands (e.g., agriculture, residential, industrial), while four-fifths of all large cities that withdraw surface water are exposed to treated wastewater in their supplies.

Water sources and kidney function: investigating chronic kidney disease of unknown etiology in a prospective study

A chronic Kidney Disease of unknown etiology (CKDu) has emerged with disproportionately high prevalence across dry lowland agricultural communities globally. Here we present the results of a prospective cohort of 293 patients with CKDu in the endemic region of Wilgamuwa, Sri Lanka, in whom we measured baseline kidney function and undertook quarterly follow up over 2 years. Well water was the primary historic drinking water source in the region, although a majority (68%) of participants reported switching to reverse osmosis water during study follow ups. Participants who reported ever drinking from well water had estimated glomerular filtration rates −6.7 (SD: 2.8) ml/min/1.73 m2 lower than participants who did not drink from well water historically (p = 0.0184) during the study period. Geospatial analysis identifies a cluster within the region where CKDu progression is significantly higher than the surrounding area. Samples of household wells (n = 262) indicated 68% had detectable agrochemical compounds with concentration above global water quality standards. It is expected that the detected contaminants compounds are indicators of poor water quality and that there is likely additional agrochemical exposure including commercial additives that may contribute to CKDu onset and/or progression. Thus, our study finds that well water exposure during a person’s lifetime in this region is associated with kidney function decline and identifies and quantifies putative nephrotoxic agrochemicals above safe drinking water concentrations in these wells.