Spatial assessment of tap water safety in China and associated health impacts

The quality of municipal water supplies is of fundamental importance to public health and national security. Here, we assess the tap water quality in 31 provinces across China and examine the effects of natural and anthropogenic conditions on water quality and associated health risks. Precipitation is a crucial factor influencing the organic matter content and ionic conductivity in tap water, especially for arid and semi-arid regions. Although the concentration of disinfection byproducts (DBPs) is closely related to the organic matter content, the occurrence of highly toxic DBPs was more significantly affected by anthropogenic factors such as economic development and pollution emission. We confirmed nanofiltration as an effective point-of-use treatment to reduce the adverse effects of DBPs in public water supplies. Since DBPs in tap water is a long-term global problem, our results highlight the potential health hazards of drinking water brought about by social development and conclude that countries and regions with rapid development might face high DBP toxicity.

Developing Enterprise Water Targets Informed by Local Contexts: Cargill’s Approach

In response to growing threats to clean water supplies due to climate change, growing populations and demand, and weak governance, many companies are assessing water risks to their operations. Increasingly, companies are recognizing that their dependencies and impacts on water can occur outside of their direct operations and are responding by setting enterprise-wide contextual water targets that reflect water challenges in priority locations across their value chains. This Practice Note documents the approach that WRI and Cargill followed to set enterprise-wide contextual water targets.

Salinity Contributions from Geothermal Waters to the Rio Grande and Shallow Aquifer System in the Transboundary Mesilla (United States)/Conejos-Médanos (Mexico) Basin

Freshwater scarcity has raised concerns about the long-term availability of the water supplies within the transboundary Mesilla (United States)/Conejos-Médanos (Mexico) Basin in Texas, New Mexico, and Chihuahua. Analysis of legacy temperature data and groundwater flux estimates indicates that the region’s known geothermal systems may contribute more than 45,000 tons of dissolved solids per year to the shallow aquifer system, with around 8500 tons of dissolved solids being delivered from localized groundwater upflow zones within those geothermal systems. If this salinity flux is steady and eventually flows into the Rio Grande, it could account for 22% of the typical average annual cumulative Rio Grande salinity that leaves the basin each year—this salinity proportion could be much greater in times of low streamflow. Regional water level mapping indicates upwelling brackish waters flow towards the Rio Grande and the southern part of the Mesilla portion of the basin with some water intercepted by wells in Las Cruces and northern Chihuahua. Upwelling waters ascend from depths greater than 1 km with focused flow along fault zones, uplifted bedrock, and/or fractured igneous intrusions. Overall, this work demonstrates the utility of using heat as a groundwater tracer to identify salinity sources and further informs stakeholders on the presence of several brackish upflow zones that could notably degrade the quality of international water supplies in this developed drought-stricken region.

Temporal analysis of rainfall and drought characteristics over Jalore District of S-W Rajasthan

Drought forecasting is being considered an important tool to help understand the rainfall pattern and climate change trend. Drought is a prolonged period of months or years in which an area, whether surface water or groundwater, becomes insufficient in its water supplies. Drought is considered as most difficult but least known environmental phenomenon, impacting more persons than any other. There are several indices used to classify droughts. For this study, precipitation-based drought indices are considered (i.e., SPI, RAI and Percentage Departure of Rainfall). The objective of the research is to examine and determine the possible rainfall trends over the Jalore district of South-West Rajasthan in Luni river basin. In this research, trend analysis using the rainfall data from the years 1901 to 2021 was carried out on monthly, seasonal and annual basis. To define the current trend path, the Mann-Kendall test and Sen's slope estimator test were used. In order to detect the trend and its change in magnitude over a particular period of time, Sen's slope estimator was used. During the southwest monsoon, declining rainfall leads to short-term meteorological droughts, which have severe effect on the agriculture sector and Jalore district's water supplies, while rising rainfall during other seasons tends to mitigate the severity of drought. The result of research reveals that there is rise of pre-monsoon and post-monsoon rainfall, but it also depicts a fall in the annual rainfall which reflects in reduced Winter and S-W monsoon rainfall.

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.

A decay of rights: The decision in New Health New Zealand Inc v South Taranaki District Council

<p>The decision in New Health New Zealand Inc v South Taranaki District Council is the most recent legal development in the New Zealand debate about fluoridation of public water supplies. That decision centred on the interpretation of section 11 of the New Zealand Bill of Rights Act, the right to refuse medical treatment. The Court held that the fluoridation in question was legal, and reached a limited definition of medical treatment that did not encompass fluoridation. This paper analyses the reasoning leading to that interpretation, concluding that the decision is problematic and that the definition of s 11 needs to be remedied. The use of the wording of s 11 to limit the definition of medical treatment was inappropriate, as was the policy reasoning used to support that limitation. The structure of reasoning followed exacerbated these issues and adhered too closely to the reasoning in United States cases. Furthermore, the application of a de minimis threshold was conducted without adequate scrutiny, and such a threshold should not be applied to s 11.</p>

A decay of rights: The decision in New Health New Zealand Inc v South Taranaki District Council

<p>The decision in New Health New Zealand Inc v South Taranaki District Council is the most recent legal development in the New Zealand debate about fluoridation of public water supplies. That decision centred on the interpretation of section 11 of the New Zealand Bill of Rights Act, the right to refuse medical treatment. The Court held that the fluoridation in question was legal, and reached a limited definition of medical treatment that did not encompass fluoridation. This paper analyses the reasoning leading to that interpretation, concluding that the decision is problematic and that the definition of s 11 needs to be remedied. The use of the wording of s 11 to limit the definition of medical treatment was inappropriate, as was the policy reasoning used to support that limitation. The structure of reasoning followed exacerbated these issues and adhered too closely to the reasoning in United States cases. Furthermore, the application of a de minimis threshold was conducted without adequate scrutiny, and such a threshold should not be applied to s 11.</p>

Changes in glacial lakes in the Poiqu River basin in the central Himalayas

The Poiqu River basin is an area of concentration for glaciers and glacial lakes in the central Himalayas, where 147 glacial lakes were identified, based on perennial remote sensing images, with lake area ranging from 0.0002 to 5.5 km2 – a total of 19.89 km2. Since 2004, the retreat rate of glacier has reached as high as 5.0 km2 a−1, while the growth rate of glacial lake has reached 0.24 km2 a−1. We take five typical lakes as our case study and find that the retreat of glacier area reaches 31.2 %, while the glacial lake area has expanded by 166 %. Moreover, we reconstruct the topography of the lake basin to calculate the water capacity and propose a water balance equation (WBE) to explore the lake evolution. By applying the WBE to the five lakes, we calculate the water supplies of the last few years and compare this with the results of field surveys, which are in agreement, within an error of only 1.86 % on average. The WBE also reveals that the water supplies to the lake depend strongly on the altitude. Lakes at low altitudes are supplied by glacier melting, and lakes at high altitudes are supplied by snowmelts. The WBE is not only applicable for predicting future changes in glacial lakes under climate warming conditions but is also useful for assessing water resources from rivers in the central Himalayas.

The Alliance of Community-Owned Water Services in Europe: Opportunities and Challenges Based on the Irish Perspective

The foundation of the Alliance of Community-Owned Water Services in Europe (ACOWAS-EU), established during the consultation period for the 2020 recast of the European Drinking Water Directive, has shone a new light on community-owned drinking water supplies (CoDWS). CoDWS are drinking water supplies that are administered, managed, and owned by the local community membership that each supply serves. This paper reviews the presence of CoDWS within the five founding regions of ACOWAS-EU—Austria, Denmark, Finland, Galicia in Spain, and Ireland—and the co-operative model structure that underpins the sector. Although the co-operative structure for CoDWS has been prominent since the mid-20th century (and sometimes even earlier), there is a dearth of research into the sector’s importance and existence in an international context. Through a detailed case study, the Irish CoDWS sector (known in Ireland as the group water scheme sector) is analysed in depth, in terms of both its evolution and the opportunities and challenges it faces today. Areas, such as water quality, biodiversity, education, and community-involvement are discussed in particular, providing key learnings that may also be of benefit to the other CoDWS sectors within ACOWAS-EU and further afield.