public water systems
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2021 ◽  
Vol 23 ◽  
Author(s):  
Seraphina Vasilodimitrakis-Hart

This article examines the design and social impact of waterways in Athens in the early 5thC BCE. While the Athenian political landscape transitioned from a series of tyrannies to democracy at the end of the Archaic period (ca. 650-480 BCE), the archaeological record also shows widespread innovation in the development of public water systems, particularly in sanitation and water supply. A movement away from buildings constructed by the Athenian tyrants facilitated the development of the Classical Agora and the creation of new public-use spaces and structures, like the Southeast Fountain House and the Great Drain in the Agora. The fountain has long been identified with the famous Peisistratid Enneakrounos (“Nine Spouts”) fountain, but through investigation into the arguments of J.M. Camp and Jessica Paga, I propose that a later date ca. 500 BCE is more suitable for the historical and archaeological context of the fountain.  I investigate several Athenian waterworks built/maintained during the late Archaic period to the Classical period (~500-323 BCE): the Great Drain in the Agora, the Southeast Fountain House, the Klepsydra fountain, and the Asklepieion on the Akropolis. The works of Hippocrates, Thucydides, and—to a lesser extent—Pausanias, inform my examination of the implications of the construction of these waterworks and the development of democracy in the 5th century. These waterways show a dedicated shift from the private use of water and tyrannical building works, to a new, fully public and communal mode of engagement with the city and its resources.


Author(s):  
Fahad Alzahrani ◽  
Alan R. Collins

Abstract Water supply unreliability in many public water systems stems from aging infrastructure. We measure unreliability by the issuance of boil water notices (BWNs) within one year prior to single-family residential sale observations. Using a spatial quantile regression framework on transactions between 2012 and 2017, we find statistically significant, negative relationships between BWNs and residential properties. The estimated impacts of unreliability on residential housing prices, however, are not uniform across the distribution of prices. Specifically, we find that BWNs have a larger impact on medium- to low-priced houses (at or below the 60 percent quantile) compared with high-priced houses. An aggregate marginal willingness-to-pay value of $4.2 million was computed for a one-day reduction in annual BWN throughout Marion County.


2021 ◽  
Author(s):  
Ashok Kumar ◽  
Kaman Singh ◽  
Utkarsh Dixit ◽  
Rayees Ahmad Bhat ◽  
Satya Prakash Gupta

Water is one of the most essential requirements for living being to survive because 70–80% of the mass of most living bodies consists of water and various mineral and organic salts . Water is also most important component of our environment. Large amount of water is used in various industries or commercial level or domestic level and finally effluent water is loaded with large amount of pollutants such as organic chemicals (surfactants, dyes, phenols etc.), inorganic hazardous heavy metals (As in present case) microbes (bacteria, fungi etc.) pollutants particulate etc. Arsenic is a natural metalloid chemical that may be present in groundwater and surface water gets polluted, hence, aquatic life of plants and animals is disturbed and cause abnormal growth and various diseases, hence, short term or long term changes occurs in ecosystem. Hence, treatment of wastewater is essentially required before discharge effluent wastewater into ponds or lagoons, drains and rivers. Arsenic is one such element that contaminates the environment as reported in several countries. The largest population at risk is in Bangladesh followed by India (West Bengal). Arsenic is familiar as silent killer because dissolved in water, it is colorless, odorless, and tasteless, yet consumption of relatively small doses of this element in its most toxic forms can cause rapid and violent death. It is a human carcinogen in water over a wide range of pH values, having harmful effects on both human health and environment, even at low concentration. Because of this effect, the World Health Organization (WHO) and the US Environmental Protection Agency (USEPA) set the arsenic standard for drinking water at .010 ppm to protect consumers served by public water systems. Ingestion only poses health problems if a dangerous amount of arsenic enters the body. Then, it can lead to cancer, liver disease, coma, and death. There is no effective treatment for arsenic toxicity. Only the removal of arsenic from aqueous system can prevent the toxicity. A great deal of research over recent decades has been done to lower the concentration of arsenic in drinking water and still there is a need to develop ecofriendly techniques. Existing major arsenic removal technologies include oxidation, adsorption, precipitation, coagulation and membrane separation. This book chapter presents a systematic description of current status of research in the area of arsenic removal from contaminated water and comparison of all technologies available with more emphasis on adsorption.


Author(s):  
Richard J. Weisman ◽  
Larry B. Barber ◽  
Kaycee Faunce ◽  
Jennifer L. Rapp ◽  
Celso M. Ferreira

Abstract Temporal variations of de facto wastewater reuse are relevant to public drinking water systems (PWSs) that obtain water from surface sources. Variations in wastewater discharge flows, streamflow, de facto reuse, and disinfection by-products (DBPs – trihalomethane-4 [THM4] and haloacetic acid-5 [HAA5]) over an 18-year period were examined at 11 PWSs in the Shenandoah River watershed, using more than 25,000 data records, in gaged and ungaged reaches. The relationship of de facto reuse with DBPs by year and quarter at the PWSs was examined. A linear relationship was found between THM4 and de facto reuse on an annual average basis (p = 0.050), as well as in quarters 3 (July – September) (p = 0.032) and 4 (October – December) (p = 0.031). Using a t-test (p < 0.05), the study also showed that there were significant differences in DBP levels for PWSs relative to 1% de facto reuse. This was found for THM4 based on annual average and quarter 1 (January – March) data, and for HAA5 based on quarter 3 data during the period of record.


Author(s):  
Alesha K. Thompson ◽  
Michele M. Monti ◽  
Matthew O. Gribble

The United States Environmental Protection Agency monitors contaminants in drinking water and consolidates these results in the National Contaminant Occurrence Database. Our objective was to assess the co-occurrence of metal contaminants (total chromium, hexavalent chromium, molybdenum, vanadium, cobalt, and strontium) over the years 2013–2015. We used multilevel Tobit regression models with state and water system-level random intercepts to predict the geometric mean of each contaminant occurring in each public water system, and estimated the pairwise correlations of predicted water system-specific geometric means across contaminants. We found that the geometric means of vanadium and total chromium were positively correlated both in large public water systems (r = 0.45, p < 0.01) and in small public water systems (r = 0.47, p < 0.01). Further research may address the cumulative human health impacts of ingesting more than one contaminant in drinking water.


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