Unintended consequences of water conservation on the use of treated municipal wastewater

Nature Portfolio (Springer Nature) | May 11th, 2020

Municipal water managers are intensifying efforts to reduce urban water use and increase the reliability of local water supplies to combat rising water scarcity and droug

Municipal water managers are intensifying efforts to reduce urban water use and increase the reliability of local water supplies to combat rising water scarcity and drought. Incentivizing increases in water-use efficiency and mandating conservation are two strategies to rein in demand. Concurrently, local water supplies are being augmented through investments in reclaiming and treating municipal wastewater. Although reducing urban water consumption is necessary to deal with population growth and a more variable climate, it does come at a cost. In particular, cutting back on indoor water consumption impacts the generation and quality of wastewater, which can have widespread and underappreciated consequences on human society and the environment. Here, to quantify these impacts, we tracked monthly effluent flow, salinity levels and the properties of 34 wastewater treatment plants throughout Southern California from 2013 to 2017—a period that included extreme drought and abundant precipitation. Our analysis demonstrates that conservation measures significantly reduced effluent flow and increased effluent salinity (P value ≤ 0.05). Our findings further highlight the need for policymakers to recognize the interdependencies and complexities within a water system.

United States v. State Water Resources Control Board (1986)

Court of Appeals of California, First Appellate District | May 28th, 1986

This appeal raises a number of novel and complex questions concerning the interrelationship of the law of water quality and the law of water rights. The coordinated cases

This appeal raises a number of novel and complex questions concerning the interrelationship of the law of water quality and the law of water rights. The coordinated cases arise out of efforts by the State Water Resources Control Board (the Board) to set new water quality standards for the Sacramento-San Joaquin Delta (Delta) in order to take account of the combined effects upon the Delta of the state's two massive water projects: the Central Valley Project (CVP) and the State Water Project (SWP), operated by the U.S. Bureau of Reclamation (U.S. Bureau or Bureau) and the California Department of Water Resources (DWR), respectively.

Unprecedented 21st century drought risk in the American Southwest and Central Plains

American Association for the Advancement of Science (AAAS) | February 12th, 2015

In the Southwest and Central Plains of Western North America, climate change is expected to increase drought severity in the coming decades. These regions never

In the Southwest and Central Plains of Western North America, climate change is expected to increase drought severity in the coming decades. These regions nevertheless experienced extended Medieval-era droughts that were more persistent than any historical event, providing crucial targets in the paleoclimate record for bench- marking the severity of future drought risks. We use an empirical drought reconstruction and three soil moisture metrics from 17 state-of-the-art general circulation models to show that these models project significantly drier conditions in the later half of the 21st century compared to the 20th century and earlier paleoclimatic intervals. This desiccation is consistent across most of the models and moisture balance variables, indicating a coherent and robust drying response to warming despite the diversity of models and metrics analyzed. Notably, future drought risk will likely exceed even the driest centuries of the Medieval Climate Anomaly (1100–1300 CE) in both moderate (RCP 4.5) and high (RCP 8.5) future emissions scenarios, leading to unprecedented drought conditions during the last millennium.

Unprecedented continental drying, shrinking freshwater availability, and increasing land contributions to sea level rise

American Association for the Advancement of Science (AAAS) | July 25th, 2025

Changes in terrestrial water storage (TWS) are a critical indicator of freshwater availability. We use NASA GRACE/GRACE- FO data to show that the continents have undergon

Changes in terrestrial water storage (TWS) are a critical indicator of freshwater availability. We use NASA GRACE/GRACE- FO data to show that the continents have undergone unprecedented TWS loss since 2002. Areas experiencing drying increased by twice the size of California annually, creating “mega-drying” regions across the Northern Hemisphere. While most of the world’s dry/wet areas continue to get drier/wetter, dry areas are now drying faster than wet areas are wetting. Changes in TWS are driven by high-latitude water losses, intense Central American/European droughts, and groundwater depletion, which accounts for 68% of TWS loss over non-glaciated continental regions. “Continental drying” is having profound global impacts. Since 2002, 75% of the population lives in 101 countries that have been losing freshwater water. Furthermore, the continents now contribute more freshwater to sea level rise than the ice sheets, and drying regions now contribute more than land glaciers and ice caps. Urgent action is required to prepare for the major impacts of results presented

Untapped Potential: An Assessment of Municipal and Industrial Water Efficiency Potential in the United States

Pacific Institute | October 28th, 2025

Water is one of our most precious and vital natural resources and is fundamental for human and ecological health and economic prosperity. Yet, water scarcity is a growing

Water is one of our most precious and vital natural resources and is fundamental for human and ecological health and economic prosperity. Yet, water scarcity is a growing risk for communities across the United States, due in part to natural hydrologic variability, population and economic growth, and the intensifying effects of climate change. The good news is that over the past several decades, communities across the United States have improved the efficiency of their water use, enabling growth and economic activity nationwide. Many communities have seen marked reductions in the amount of water used per person. For some, these reductions have been substantial enough that total water demand has peaked and declined even as the population and economy continue to grow. Even as traditional water sources are stressed, the opportunity to reduce demand through water efficiency remains both vast and largely untapped.

Untapped Potential: An Assessment of Urban Stormwater Runoff Potential in the United States

Pacific Institute | February 29th, 2024

In this assessment, we quantify the volumetric potential for stormwater runoff in US Census Urban Areas across the entire United States. This assessment finds that the av

In this assessment, we quantify the volumetric potential for stormwater runoff in US Census Urban Areas across the entire United States. This assessment finds that the average annual volumetric potential for urban stormwater runoff is 59.5 million acre-feet per year (AFY), or 53,100 million gallons per day (MGD). This volume is equivalent to 93% of the water withdrawals for municipal and industrial uses in 2015, though not all of this runoff is necessarily feasible or desirable to capture. We estimate that 37% of this national volume (21.9 million AFY) is generated just in coastal areas, which presents an opportunity for increased stormwater capture in areas that are less likely to face challenges related to adverse impacts on downstream water rights holders.

Unveiling the hidden chronic health risks of nano- and microplastics in single-use plastic water bottles: a review

Elsevier | June 14th, 2025

Single-use plastic products, such as water bottles, have become ubiquitous in modern society, contributing significantly to the growing problem of plastic waste in la

Single-use plastic products, such as water bottles, have become ubiquitous in modern society, contributing significantly to the growing problem of plastic waste in landfills, rivers, oceans, and natural habitats. This poses severe threats to biodiversity and ecosystem stability. The emergence of microplastics (1 µm to 5 mm) and nanoplastics (less than 1 µm) has raised alarms about their harmful effects on human health. Nanoplastics are especially hazardous due to their smaller size and enhanced ability to infiltrate the human body. There are critical gaps in the literature regarding the contamination of nano- and microplastics from single-use plastic water bottles, emphasizing the urgent need for further research. Here we review, we examine the global impact of nano- and microplastics from single-use plastic water bottles on human health, drawing insights from over 141 scientific articles. Key findings include the annual ingestion of 39,000 to 52,000 microplastic particles by individuals, with bottled water consumers ingesting up to 90,000 more particles than tap water consumers. The literature reveals variations in the number of nano- and microplastics particles, their sizes, and a lack of information on their physical properties. Moreover, the review highlights the chronic health issues linked to exposure to nano- and microplastics, including respiratory diseases, reproductive issues, neurotoxicity, and carcinogenicity. We highlight the challenges of standardized testing methods and the need for comprehensive regulations targeting nano- and microplastics in water bottles. This review article underscores the pressing need for expanding research, increasing public awareness, and implementing robust regulatory measures to address the adverse effects of nano- and microplastics from single-use plastic water bottles.

Unwatering the Comstock Lode

Scientific American | November 4th, 1899

AN operation of immense interest to miners and mining generally has been in progress for the past five months in Nevada, in the district embracing the well known Comsto

AN operation of immense interest to miners and mining generally has been in progress for the past five months in Nevada, in the district embracing the well known Comstock mines. The remarkable circumstances connected with the discovery and development of the wonderful lode upon which these famous mines are located is a matter of comparatively recent history—too recent to require more than a passing reference. The wild speculation, which followed their discovery, forms one of the most thrilling pages of the annals of the Far West. It is estimated that up to the year 1886 the assay value of the gold and silver extracted from these mines amounted to $500.000,000. It was during this period of greatest production that the race of California multi-millionaires arose. Up to 1886 the exploration of all the territory embraced in the Comstock lode was industriously pursued, one shaft reaching a depth of 3,300 feet, but the exhaustion of ore bodies of high grade and the large expense attending milling and mining together with the heavy tax necessary in controlling the enormous volumes of water which every where flowed from the ground caused an abandonment of all mining below the 1,600-foot level. Another element of difficulty was the high temperatures experienced on the deeper levels, which increased as the shafts were lowered until miners were able only to work in shifts of a few moments in length. In a few months the water arose to within 1,640 feet of the surface opening of the Consolidated California and Virginia shaft, and at that level it has remained for nearly thirteen years. Above this level mining has been prosecuted with some success since the lower levels were flooded, and it is now believed that all pay ore bodies above the 1,600-foot level are practically exhausted.

Update on an Analysis of a Potential Groundwater Storage and Recovery Program in the Carpinteria Groundwater Basin

Montecito Water District (MWD) | March 11th, 2025

Updated Groundwater Sustainability Plan, San Joaquin Valley – Tule, Alpaugh Groundwater Sustainability Agency

Alpaugh Groundwater Sustainability Agency | July 27th, 2022

Alpaugh GSA is part of the Tule Subbasin and was formed in May 2016 for the purpose of complying with the SGMA. This updated GSP complies with the SGMA by addressing the

Alpaugh GSA is part of the Tule Subbasin and was formed in May 2016 for the purpose of complying with the SGMA. This updated GSP complies with the SGMA by addressing the DWR GSP Emergency Regulations in § 354.2 through 354.10. The GSP is the result of a collaborative process between local water agencies, technical experts, environmental managers, and community members with a mutual goal of sustainably managing the groundwater basin. Alpaugh GSA is one of seven participating GSAs in the Tule Subbasin, which organize their activities through the updated Tule Subbasin Coordination Agreement (Coordination Agreement). Due to size this file has been divided. Part 1, Part 2, Part 3, Part 4, Part 5