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Environmental DNA (eDNA) sampling is a powerful tool for rapidly characterizing biodiversity patterns for specious, cryptic taxa with incomplete taxonomies. One such group that are also of high conservation concern are North American freshwater gastropods. In particular, springsnails of the genus Pyrgulopsis (Family: Hydrobiidae) are prevalent throughout the western United States where >140 species have been described. Many of the described species are narrow endemics known from a single spring or locality, and it is believed that there are likely many additional species which have yet to be described. The distribution of these species across the landscape is of interest because habitat loss and degradation, climate change, groundwater mining, and pollution have resulted in springsnail imperilment rates as high as 92%. Determining distributions with conventional sampling methods is limited by the fact that these snails are often <5 mm in length with few distinguishing morphological characters, making them both difficult to detect and to identify. We developed an eDNA metabarcoding protocol that is both inexpensive and capable of rapid, accurate detection of all known Pyrgulopsis species. When compared with conventional collection techniques, our pipeline consistently resulted in detection at sites previously known to contain Pyrgulopsis springsnails and at a cost per site that is likely to be substantially less than the conventional sampling and individual barcoding that has been done historically. Additionally, because our method uses eDNA extracted from filtered water, it is non‐destructive and suitable for the detection of endangered species where "no take" restrictions may be in effect. This effort represents both a tool which is immediately applicable to taxa of high conservation concern across western North America and a case study in the broader application of eDNA sampling for landscape assessments of cryptic taxa of conservation concern. [ABSTRACT FROM AUTHOR]

There are over 2.2 million miles of underground water pipes serving the cities in the United States. Many are in poor conditions and deteriorate rapidly. Failures of these pipes could cause enormous financial losses to the customers and communities. Inspection provides crucial information for pipe condition assessment and maintenance plan; it, however, is very expensive for underground pipes due to accessibility issues. Therefore, water agencies commonly face the challenge to 1) decide whether it is worthwhile to schedule expensive water pipe inspections under financial constraints, and 2) if so, how to optimize the inspection schedule to maximize its value. This study leverages the physical model and data-based ML (ML) models for underground water pipe failure prediction to shed light on these two important questions for decision making. Analyses are firstly conducted to assess the value of water pipe inspection. Results by use of a physical-based failure model and Monte Carlo simulations indicate that by inspecting pipe's condition, i.e., assessment of pipe's erosion depth, the uncertainty of water pipe failure prediction can be narrowed down by 51%. For optimal inspection schedule, an artificial neural network (ANN) model, trained with historical inspection data, is evaluated for its performance in forecasting the future pipe failure probability. The results showed that a biased pipe failure prediction can occur under limited rounds of inspection. However, incorporating more rounds of inspection allows to predict the pipe failure conditions over its life cycle. From this, an optimal inspection plan can be proposed to achieve the maximum benefits of inspection in uncertainty reduction. A few salient results from the analyses include 1) the optimal schedule for inspection is not necessarily equal in the time interval, 2) by setting the goal of uncertainty reduction, an optimal inspection schedule can be obtained, where ML (ML) model augmented by continuously training with inspection data allows to reliably predict water pipe failure conditions over its life cycle. While this study focuses on underground pipe inspection, the general observations and methodology are applicable to optimize the inspection of other types of infrastructure as well. [ABSTRACT FROM AUTHOR]

Water distribution network (WDN) leakage is estimated to account for more than 20% of potable water in the United States. Because existing leakage detection practices are mainly laborious or require excessive budget allocation, novel model-based techniques have become prevalent by employing smart meters. Specifically, incorporating machine learning and metaheuristic optimization methods into such model-based approaches to predict water pipeline leakage is one of the state-of-the-art approaches. This paper presents a predictive leakage detection approach by leveraging advanced metering infrastructure (AMI) and cyber-monitoring data. Primarily, the synchronous collection of consumption and monitoring data (i.e., flow and pressure) constitutes the proposed predictive tool in a combinative framework of genetic algorithms (GA) and particle swarm optimization (PSO). The time-consuming EPANET 2.2 simulation toolkit in MATLAB is circumvented by a set of trained artificial neural networks (ANNs). Sensitivity analyses are conducted to investigate the sensitivity of the proposed leakage prediction approach to multiple parameters. Ultimately, the number and location of the flow and pressure monitoring stations are optimized using maximum sensor availability thresholds. Mean absolute percentage error (MAPE) is employed to measure the model's accuracy. The proposed predictive tool offers insightful horizons on how considerable background leakage can be detected and prioritized without using labor-intensive, costly methods. [ABSTRACT FROM AUTHOR]

Synthetic natural gas (SNG) is of great interest in reducing fossil energy consumption while maintaining compatibility with existing NG infrastructure and end-use applications equipment. SNG can be produced using clean H 2 generated from renewable or nuclear energy and CO 2 captured from stationary sources or the atmosphere. In this study, we develop an engineering process model of SNG production using Aspen Plus® and production scales reported by the industry. We examine the levelized cost and life cycle greenhouse gas (GHG) emissions of SNG production under various CO 2 supply scenarios. Considering the higher cost of H 2 transportation compared with CO 2 transportation, we assume that CO 2 feedstock is transported via pipeline to the H 2 production location, which is collocated with the SNG plant. We also evaluate the cost of CO 2 captured from the atmosphere, assuming the direct air capture process can occur near the SNG facility. Depending on the CO 2 supply chain, the levelized cost of SNG is estimated to be in the range of $45–76 per million British thermal units (MMBtu) on a higher heating value (HHV) basis. The SNG production cost may be reduced to $27–57/MMBtu-HHV by applying a tax credit available in the United States for low-carbon H 2 production (45 V). With a lower electricity price of 3ȼ/kWh for water electrolysis and accounting for a 45 V tax credit, the SNG cost reaches parity with the cost of fossil NG. Depending on the CO 2 supply chain, SNG can reduce life cycle GHG emissions by 52–88 % compared with fossil NG. • A process model of synthetic natural gas production is developed using Aspen Plus. • SNG is produced from low-carbon/zero-carbon H 2 and point-source/atmospheric CO 2. • Levelized production cost and life cycle GHG emissions of SNG are evaluated. • SNG cost can be reduced with a tax credit in the U.S. for low-carbon H 2 production. • SNG can reduce life cycle GHG emissions by 52–88 % compared to fossil NG. [ABSTRACT FROM AUTHOR]

Introduction: Waterpipe use is common among U.S. young adults (aged 18-24 years), with estimates considerably higher than other age groups. Although studies have examined attitudes and beliefs associated with waterpipe use, no study has examined reasons for use in a nationally representative sample.Methods: Using latent class analyses, this study examined subgroups based on self-reported reasons for use of past 30-day young adult (aged 18-24 years) waterpipe users (n=1,198) from Wave 1 (2013-2014) of the Population Assessment of Tobacco and Health Study. Data analyses were conducted in 2017. Covariates included sociodemographic characteristics, substance use, and internalizing and externalizing problems.Results: A three-class model was identified: Class 1 (socializing and flavors, 57%), Class 2 (many reasons [flavors, socializing, less harmful than cigarettes, and affordability], 20%), and Class 3 (socializing, 23%). Class 3 was considered the referent group. Compared with non-Hispanic whites, non-Hispanic blacks were less likely to belong to Class 1, whereas Hispanics were more likely to belong to Class 2. Compared with less than high school education, greater than high school education was associated with membership in Class 1; however, high school graduation was associated with membership in Class 2. Past-year alcohol users compared with non-users were less likely to belong to Class 2. Past 30-day poly-tobacco users compared with non-users were more likely to belong to Class 2.Conclusions: This study revealed distinct classes of waterpipe users based on self-reported reasons for use. Findings inform targeted policies for waterpipe tobacco control as part of public health efforts to mitigate harms associated with tobacco use. [ABSTRACT FROM AUTHOR]

The substandard condition of wastewater systems in the US, accompanied by the lack of financial resources for renewal are hindering adequate operation and maintenance of deficient sewer systems. Information about current and future pipe condition, as well as information about the impact of possible pipe failures are an integral part of an efficient asset management program and can help stakeholders make the best decisions to prioritize rehabilitation and/or replacement projects. Typically, pipes in the worst structural conditions are prioritized and budgeted within the capital improvement project planning. To be able to predict future pipe conditions, many methods have been developed and successfully implemented that incorporate pipe inspection data to predict the future state of these assets. Additionally, methodologies exist for determining the consequences of pipe failures economically, socially, and environmentally. These methods have been incorporated into decision support systems (DSS) that help utility managers determine when to rehabilitate or replace their assets. DSS for trenchless pipe renewal allow utility managers to determine the most suitable method to renew their assets, given known defects in the pipe. The aim of this paper is to provide a review of risk management methods that allow pipeline managers to estimate likelihood of failure and quantify consequence of failure of sewer pipes. Additionally, an updated review of existing DSS for trenchless pipe rehabilitation is presented and analyzed. Finally, recommendations are made to improve existing methods to make the risk management process for trenchless rehabilitation decision making more efficient and practical. [ABSTRACT FROM AUTHOR]

This article summarizes findings from two AWWA-sponsored surveys of US community water systems (CWSs) that were conducted to gather information on lead-containing service lines (LSLs) in different regions of the United States for different sizes (population ranges) of water systems. The major objective of this research was to estimate the number of water systems with LSLs and the approximate number of LSLs nationwide and by region. These estimates were ultimately extrapolated to state occurrence. The survey results indicated a national estimate of 6.1 million LSLs (either full or partial) currently present in CWSs of the United States, compared with 10.2 million estimated at the time of the original Lead and Copper Rule (LCR) (USEPA 1991); approximately 11,200 CWSs currently have LSLs compared with more than 15,000 estimated in the original LCR; 15 to 22 million people served by CWSs are estimated to have either a full or partial LSL serving their home out of a total population served by CWSs of about 293 million (7%); and approximately 30% of the CWSs surveyed (national average) reported having some LSLs in their system. [ABSTRACT FROM AUTHOR]

The article explores the approaches undertaken by the nonprofit group American Water Works Association (AWWA) in conceptualizing standards that recognize technologies. Topics discussed include the revisions of pipeline standards and the growing challenge of the water and wastewater utilities in balancing innovation. Also emphasized is the importance of balancing the pace of innovation and to consider the standards of the AWWA to provide reliable and safe water to the public.

The article discusses the significant drinking water incidents in the U.S. in 2014. These includes the above-ground chemical storage tank that leaked 10,000 gallons of 3-methyclohexanemethanol in January 9. It notes the stormwater pipe failure in dam embankment in February 2. It mentions the algal bloom on Lake Erie on August 9, 2014.

The article focuses on the infrastructure renewal strategy implemented by the Miami-Dade Water and Sewer Department (WASD) to address the aging water and sewer infrastructure in the U.S. It says that infrastructure report of the WASD highlights the areas of concern including the reduction of the dependency on pipelines. Moreover, advanced nondestructive electromagnetic (EM) technology is used by the WASD to determine the location of wire breaks.

Consumers face numerous problems when they experience leaks and premature failures in their potable drinking water plumbing system. A review of an existing database of copper pipe failures demonstrated that premature pipe failures and pinhole leaks have been documented across the United States. Additionally, there are “hotspots” in the United States where pinhole failures have been documented to occur at a fairly high incidence. A number of known and suspected factors can cause copper pitting corrosion that eventually develops into a pinhole leak, such as specific water qualities, microbial activity, hydraulics, and other installation factors. However, the current understanding does not adequately define the complex synergy between causal factors, which poses a challenge in assessing plumbing susceptibility and shaping an effective management plan. This work presents a preliminary ranking of the causal factors for assessing plumbing susceptibility. However, due to incomplete understanding of the pinhole phenomenon, advice from local experts and past service history should still be given priority in assessing the likelihood of problems. [ABSTRACT FROM AUTHOR]

Repair and maintenance of existing distribution lines is an increasing concern for water utilities. While pipe lining activities are effective and generally less expensive than complete replacement, they still represent considerable time and expense. This study provides guidance on the best practices to minimize the amount of time that customers are without water service, must endure restricted service, or are served by less secure networks due to pipe lining activities. Nine utilities provided benchmarking data to identify efficient operations. Statistical analysis indicates that minor changes to task sequencing and materials may improve efficiencies by several hours to several days. However, in order to obtain a rapid lining operation, utilities must promote extensive changes to pipe lining philosophy and to the disinfectant approach. While a rapid disinfectant approach (less than 24 h) is not typically adopted by United States utilities, preliminary testing indicates that addressing the newly lined pipe with “main break” disinfection procedures can achieve satisfactory results at a significantly reduced time. [ABSTRACT FROM AUTHOR]

The concentrations of total, colloidal, and truly dissolved lead (Pb) were investigated in tap water following laboratory simulations of partial lead pipe replacements. Old lead pipes were recovered from service in New Orleans, La and mounted horizontally in an experimental apparatus at Tulane Univ. Municipal water was diverted for two weeks at low flowrates of 0.2 or 1.1 L/min (0.05 or 0.3 gal/min) through two pipe trains operated continuously and two pipe trains operated intermittently. Samples were collected to determine relative concentrations and time needed for each form of Pb (total, colloidal, and truly dissolved) to stabilize below the U.S. Environmental Protection Agency action level (AL) of 15 μg/LPb. Results demonstrate that total Pb concentrations exceeded the AL immediately following simulated partial pipe replacements. In most cases, total Pb concentrations were reduced below the AL by flushing for 15–30 min but subsequent sampling revealed total Pb concentrations greater than the AL. Continuous flow pattern flushing was more effective at stabilizing total Pb concentrations below the AL than intermittent flows. Results also demonstrate that colloidal Pb concentrations were 38–54% of total Pb and truly dissolved Pb concentrations were 41–60% of total Pb concentrations after stabilization. [ABSTRACT FROM AUTHOR]

The article offers U.S. health news briefs through referencing "The Nation's Health" periodical. Legislative bills in U.S. states have reduced nonmedical exemptions for refusing vaccines, within the context of measles cases in the U.S, are discussed. There have been increases in the replacement of lead water pipes in the U.S. to reduce lead toxicity in water.

The article reports on establishment of the Natural Resource Investment Center by the U.S. Department of the Interior for economic development of the nation. Topics discussed include increase of investment in water conservation and water infrastructure, development of financing sources in order to create investments for water supply bounds such as storage and pipelines, and identification of opportunities for private sector investments.

Condition assessment of wastewater collection systems is a vital part of a utility's asset management program. Reliable information on pipe condition is needed to prioritize rehabilitation and replacement projects, given the current state of our nation's infrastructure. Although inspections with conventional closed-circuit television (CCTV) have been the mainstay of pipeline condition assessment for decades, other technologies are now commercially available. Five of these innovative technologies were selected for field trials under the U.S. Environmental Protection Agency (USEPA) demonstration program: zoom camera, electroscanning, digital scanning, laser profiling, and sonar. The goal of the field demonstration was to evaluate the technical performance and cost of these technologies. The field demonstration was conducted in August 2010 and was hosted by the Kansas City, Missouri Water Services Department. The innovative technologies were compared to CCTV inspection. Each technology identified maintenance and structural defects by collecting data or images of the pipe condition. The camera technologies (i.e., digital scanning, zoom camera, and CCTV) and laser scanning provided pipe condition above the water line, whereas sonar assessed conditions below the water line. Electroscanning detected leakage-related defects anywhere along the pipe circumference. Costs were compared for different inspection technologies based on actual costs for planning, field work, data analysis, and reporting. Total costs for the multisensor (digital, laser, and sonar scanning) inspection were $14.71 per m of pipeline inspected as compared to $10.31 per m for electroscanning, $3.46 per m for zoom camera, and $9.78 to $10.48 per m for CCTV. [ABSTRACT FROM AUTHOR]