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Given impending regulations, a study of community water systems found challenges in defining, identifying, and funding remediation of the galvanized pipe associated with lead service lines. [ABSTRACT FROM AUTHOR]

The inner walls of the drinking water distribution system (DWDS) are expected to be clean to ensure a safe quality of drinking water. Complex physical, chemical, and biological processes take place when water comes into contact with the pipe surface. This paper describes the impact of leaching different compounds from the water supply pipes into drinking water and subsequent risks. Among these compounds, there are heavy metals. It is necessary to prevent these metals from getting into the DWDS. Those compounds are susceptible to impacting the quality of the water delivered to the population either by leaching dangerous chemicals into water or by enhancing the development of microorganism growth on the pipe surface. The corrosion process of different pipe materials, scale formation mechanisms, and the impact of bacteria formed in corrosion layers are discussed. Water treatment processes and the pipe materials also affect the water composition. Pipe materials act differently in the flowing and stagnation conditions. Moreover, they age differently (e.g., metal-based pipes are subjected to corrosion while polymer-based pipes have a decreased mechanical resistance) and are susceptible to enhanced bacterial film formation. Water distribution pipes are a dynamic environment, therefore, the models that are used must consider the changes that occur over time. Mathematical modeling of the leaching process is complex and includes the description of corrosion development over time, correlated with a model for the biofilm formation and the disinfectants–corrosion products and disinfectants–biofilm interactions. The models used for these processes range from simple longitudinal dispersion models to Monte Carlo simulations and 3D modeling. This review helps to clarify what are the possible sources of compounds responsible for drinking water quality degradation. Additionally, it gives guidance on the measures that are needed to maintain stable and safe drinking water quality. [ABSTRACT FROM AUTHOR]

The inner walls of the drinking water distribution system (DWDS) are expected to be clean to ensure a safe quality of drinking water. Complex physical, chemical, and biological processes take place when water comes into contact with the pipe surface. This paper describes the impact of leaching different compounds from the water supply pipes into drinking water and subsequent risks. Among these compounds, there are heavy metals. It is necessary to prevent these metals from getting into the DWDS. Those compounds are susceptible to impacting the quality of the water delivered to the population either by leaching dangerous chemicals into water or by enhancing the development of microorganism growth on the pipe surface. The corrosion process of different pipe materials, scale formation mechanisms, and the impact of bacteria formed in corrosion layers are discussed. Water treatment processes and the pipe materials also affect the water composition. Pipe materials act differently in the flowing and stagnation conditions. Moreover, they age differently (e.g., metal-based pipes are subjected to corrosion while polymer-based pipes have a decreased mechanical resistance) and are susceptible to enhanced bacterial film formation. Water distribution pipes are a dynamic environment, therefore, the models that are used must consider the changes that occur over time. Mathematical modeling of the leaching process is complex and includes the description of corrosion development over time, correlated with a model for the biofilm formation and the disinfectants–corrosion products and disinfectants–biofilm interactions. The models used for these processes range from simple longitudinal dispersion models to Monte Carlo simulations and 3D modeling. This review helps to clarify what are the possible sources of compounds responsible for drinking water quality degradation. Additionally, it gives guidance on the measures that are needed to maintain stable and safe drinking water quality.

Key Takeaways: Lead service line replacement (LSLR) is a cost‐effective and popular policy decision. The Water Infrastructure Fund Transfer Act (WIFTA) was a small, idiosyncratic program designed to help Newark, N.J., through its lead crisis. WIFTA was a mixed success but spawned a larger push for expanded federal funding for LSLR; more funding is possible if existing funding programs deliver faster replacement. [ABSTRACT FROM AUTHOR]

Compliance, Service Lines, Lead, Community Water System, Lead and Copper Rule, Lead Pipe, Water Systems Keywords: Compliance; Service Lines; Lead; Community Water System; Lead Pipe; Lead and Copper Rule; Water Systems EN Compliance Service Lines Lead Community Water System Lead Pipe Lead and Copper Rule Water Systems 6 8 3 03/11/22 20220301 NES 220301 The federal Lead and Copper Rule Revisions (LCRR) published Jan. 15, 2021, in the I Federal Register i are now effective, and compliance will be required Oct. 16, 2024. [Extracted from the article]

Copyright of Journal: American Water Works Association is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

US corrosion control practice often assumes that the orthophosphate component of blended phosphate corrosion inhibitors causes the formation of low-solubility lead–orthophosphate solids that control lead release into drinking water. This study identified the solids that formed on the interior surface of a lead service line and a galvanized steel pipe excavated from a system using a proprietary blended phosphate chemical. The scale was analyzed by X-ray diffraction, X-ray fluorescence, and scanning electron microscopy/energy dispersive spectroscopy. Instead of crystalline lead–orthophosphate solids, a porous amorphous layer rich in aluminum, calcium, phosphorus, and lead was observed at the lead pipe scale–water interface. Thus, the mechanism inhibiting lead release into the water was not a thermodynamically predictable passivating lead–orthophosphate scale, but rather an amorphous barrier deposit that was possibly vulnerable to disturbances. Galvanized pipe scales showed relatively crystalline iron and zinc compounds, with additional surface deposition of aluminum, phosphorus, calcium, and lead. [ABSTRACT FROM AUTHOR]

A recent Water Research Foundation report evaluated lead service line (LSL) lining and coating technologies as an alternative to LSL replacement in some situations. Although apples‐to‐apples price comparisons with pipe replacement strategies aren't provided, the report points to instances where lining and coating technologies may be of value to utility customers and water utilities. [ABSTRACT FROM AUTHOR]

The Dor C shipwreck is the remains of a 60-t schooner that plied the Mediterranean during the last decades of the nineteenth century. The various building materials and ceramic ware found inside the shipwreck suggest an established commercial route between southern France and the Holy Land. Three metal objects were found in the bow area of the shipwreck: a lead pipe, an iron rigging hoop, and a brass wick housing. This study aims to understand their manufacturing processes, to propose possible dating and manufacturing locations, and to verify their use. The metallurgical investigation suggests that the objects were designated for marine use and manufactured using processes developed during the second half of the nineteenth century, probably post-1885, which supports the dating of the ship. The tonnage of the ship, the origin of her cargo, the provenance of some of the metal parts, and the location of the shipwreck, all suggest that her last voyage was a delivery of cargo from Marseilles to Dor. [ABSTRACT FROM AUTHOR]

Effective communication to citizens is of prime importance during public health crises involving water. This paper takes a sequential mixed method approach to the problem of communicating drinking water risks prevention of exposure to health risks in cities. City water officials are interviewed to learn about the goals of their drinking water communications strategies, and household surveys are completed subsequently in three suburbs in Saskatoon, Saskatchewan Canada to assess the effectiveness of communications for drinking water risks and advisories, and household resident’s knowledge of, and reported adherence to those advisories. Residents described how they heard about EBWA and PDWA’s, and lead pipe replacement programs; whether suggested protocols were followed; and how residents were informed about the termination of the advisories. Official communication efforts advised 21.4% of respondents directly about drinking water risks, however, the residents’ use of multiple unofficial information sources demonstrates an opportunity for increased resilience through having many pathways for receiving water advisory information. Communicating through word of mouth, in person and through social networks, reached 71% of respondents. Suburb-based differences in EBWA and PDWA communication effectiveness were also revealed. Lessons for how small cities could more effectively communicate urgent drinking water security issues and longer-term drinking water risks due to aging infrastructure are discussed. Implications for public health officers are explored. [ABSTRACT FROM AUTHOR]

Phosphate dosing is the principle strategy used in the United Kingdom to reduce the concentration of lead in tap waters supplied by lead water pipes. The mechanisms of phosphate-mediated lead control are not fully understood, but solid solutions of lead calcium apatite are thought to play an important role. This study investigated the microstructure of a lead pipe, supplied with high-alkalinity tap water, in which the lead calcium apatite crystals were spherulitic having rounded and dumb-bell-shaped morphologies. XRD, Fourier transform infrared spectroscopy, optical microscopy, Raman spectroscopy, scanning electron microscopy, and energy-dispersive spectroscopy showed that the lead pipe had a well-established inner layer of litharge; a middle layer containing lead calcium apatite spherulites, plumbonacrite, and some hydrocerussite; and an outer layer containing iron, lead, phosphorus, calcium, silicon, and aluminum. It was found that spherulitic lead calcium apatite could be grown in the laboratory by adding hydrocerussite to synthetic soft and hard water-containing phosphate, chloride, and citrate ions at pH 5.5 but not when the citrate was absent. This suggests that dissolved organic molecules might play a role in spherulite formation on lead water pipes. These molecules might inhibit the formation of lead calcium apatite, reducing the effectiveness of phosphate dosing in lead water pipes.

In the second half of the nineteenth century, many American cities built water systems using lead or iron service pipes. Municipal water systems generated significant public health improvements, but these improvements may have been partially offset by the damaging effects of lead exposure through lead water pipes. We study the effect of cities' use of lead pipes on homicide between 1921 and 1936. Lead water pipes exposed entire city populations to much higher doses of lead than have previously been studied in relation to crime. Our estimates suggest that cities' use of lead service pipes considerably increased city-level homicide rates. [ABSTRACT FROM AUTHOR]

Cumulative changes in chemical and biological properties associated with higher 'water age' in distribution systems may impact water corrosivity and regulatory compliance with lead and copper action levels. The purpose of this study was to examine the effects of water age and chemistry on corrosivity of various downstream premise plumbing pipe materials and configurations using a combination of controlled laboratory studies and a field survey. Examination of lead pipe, copper pipe with lead solder, and leaded brass materials in a replicated lab rig simulating premise plumbing stagnation events indicated that lead or copper release could increase as much as ∼440 % or decrease as much as 98 % relative to water treatment plant effluent. In field studies at five utilities, trends in lead and copper release were highly dependent on circumstance; for example, lead release increased with water age in 13 % of cases and decreased with water age in 33 % of conditions tested. Levels of copper in the distribution system were up to 50 % lower and as much as 30 % higher relative to levels at the treatment plant. In many cases, high-risks of elevated lead and copper did not co-occur, demonstrating that these contaminants will have to be sampled separately to identify 'worst case' conditions for human exposure and monitoring. [ABSTRACT FROM AUTHOR]

This paper examines the effect of waterborne lead exposure on infant mortality in American cities over the period 1900 to 1920. Variation across cities in water acidity and the types of service pipes, which together determined the extent of lead exposure, identifies the effects of lead on infant mortality. In 1900, a decline in exposure equivalent to an increase in pH from 6.675 (25th percentile) to 7.3 (50th percentile) in cities with lead-only pipes would have been associated with a decrease in infant mortality of 7% to 33%, or at least twelve fewer infant deaths per 1,000 live births. [ABSTRACT FROM AUTHOR]

It is now universally accepted that utilization of lead for domestic purposes and water distribution presents a major health hazard. The ancient Roman world was unaware of these risks. How far the gigantic network of lead pipes used in ancient Rome compromised public health in the city is unknown. Lead isotopes in sediments from the harbor of Imperial Rome register the presence of a strong anthropogenic component during the beginning of the Common Era and the Early Middle Ages. They demonstrate that the lead pipes of the water distribution system increased Pb contents in drinking water of the capital city by up to two orders of magnitude over the natural background. The Pb isotope record shows that the discontinuities in the pollution of the Tiber by lead are intimately entwined with the major issues affecting Late Antique Rome and its water distribution system. [ABSTRACT FROM AUTHOR]

Pipe connectors can significantly influence galvanic corrosion between lead and copper pipes by distancing the lead from copper pipe, introducing a third metal, and forming crevices. In this study, the effects of distance, connector material, and crevices on galvanic corrosion were examined, and bench-scale comparison testing of commercial connectors was conducted using real tap waters. Brass connectors were found to only slightly decrease (< 25%) the galvanic current that sacrifices, or corrodes, lead pipe, with higher reductions for brasses with higher zinc content. Crevices in brass connectors contained water with extremely high levels of lead (up to 9.4 x 106 µg/L); in bench-scale tests, crevices produced approximately four times more lead release to the water than did direct connections. [ABSTRACT FROM AUTHOR]

Laboratory experiments were performed to evaluate the effect of galvanic corrosion on lead release following simulated partial lead service line replacements. Experiments were conducted in a recirculating flow mode with intermittent stagnation periods using aged lead pipes harvested from Washington, D.C. Lead pipe and copper tubing were connected by brass, brass dielectric, and plastic couplings; additional experiments were performed with plastic couplings and an external wire to connect the leadand copper. Lead release increased in the order of systems connected with plastic, plastic with external wires, brass dielectric, and brass couplings. The trends are consistent with galvanic reactions between lead and copper and between lead and brass. For systems with galvanic corrosion, the increased lead release was primarily in a particulate form. Increasing the chloride-to-sulfate mass ratio from 0.7 to 7 did not increase the dissolved or total lead release. [ABSTRACT FROM AUTHOR]

Abstract: Release of lead from 80% partially replaced service lines was compared to full lead service lines using harvested–stabilized lead pipes and field brass connectors. After more than a year of stabilization, lead release was consistent with field samples. Over the relatively short duration partial replacement of lead pipe by copper pipe (3 months), generated high lead release, attributed to galvanic corrosion, resulting in a final outcome for lead release that was even worse than for a full lead pipe. Increased lead release was especially evident at higher flow rates. Orthophosphate reduced lead release from full lead pipes by 64%. For partially replaced samples with copper, lead concentrations were unchanged by phosphate dosing at moderate flow (103 ± 265 vs 169 ± 349 μg/L) and were increased to very high levels when sampled at high flow rates (1001 ± 1808 vs 257 ± 224 μg/L). The increase lead release was in the form of particulate lead (>90%). In comparison to the condition without treatment, increased sulfate treatment had little impact on lead release from 100%-Pb rigs but reduced lead release from partially replaced lead pipes with copper. Our results also raise questions concerning protocols based on short 30 min stagnation (as those used in Canada) due to their incapacity to consider particulate lead release generated mostly after longer stagnation. [Copyright &y& Elsevier]

The effect of added cupric ions (0 mg/L to 5 mg/L Cu+2) on possible deposition corrosion of lead pipe was investigated in bench-scale experiments under flowing and stagnant water conditions. Under stagnation the presence of cupric ions in the water feeding lead pipes marginally increased lead release into the water, but under continuous recirculation it could increase lead release by orders of magnitude. Other benchscale experiments investigated galvanic corrosion between lead and copper pipes under stagnation, confirming that water chemistry (particularly the chloride-to-sulfate mass ratio [CSMR]) is a controlling factor in either "strengthening" galvanic corrosion and increasing water lead contamination by orders of magnitude (high CSMR water) or "weakening" the galvanic effect with less but still significant contribution to water lead contamination (low CSMR water). Longitudinal water pH measurements along the length of the galvanic rigs revealed a significant pH drop close to the lead:copper junction at relatively short stagnation times in high CSMR water, which is consistent with the observations of higher lead leaching and higher galvanic current measured in that situation. [ABSTRACT FROM AUTHOR]

Addition of orthophosphate has been commonly employed to suppress lead levels in drinking water. Its detailed mechanism and time required for it to become effective, however, have not been fully elucidated. In this study, we investigated the mechanistic role of orthophosphate as a corrosion inhibitor in controlling lead release from tetravalent lead corrosion product PbO2 in chloraminated solutions, a system representing distribution networks experiencing disinfectant changeover from free chlorine to monochloramine. In all experiments with orthophosphate addition of at least 1 mg/L as P, peaking of soluble Pb(II) concentration within the first 24 h was observed before lead concentrations decreased and stabilized at levels lower than 15 μg/L. The variation of soluble Pb(II) concentration could be attributed to the dynamics between the rate of PbO2 reductive dissolution, primarily induced by monochloramine decomposition, and that of chloropyromorphite (Pb5(PO4)3Cl) precipitation, which did not occur until a critical supersaturation ratio of about 2.36 was reached in the solution. Our findings provide insights to how orthophosphate reduces lead levels under drinking water conditions and highlight the potential risk of short-term elevated lead concentrations. Intensive monitoring following the disinfectant changeover may be required to determine the overall lead exposure when using orthophosphate as a corrosion inhibitor. [ABSTRACT FROM AUTHOR]

Simplistic conventional models predict that a greater mass of lead will be released from lead pipes exposed to higher velocity and flow durations. However, if galvanic Pb-Cu connections are present, or if a highly protective Pb(IV) scale can be formed, reduced flow can markedly increase the mass of lead release to water and resultant consumer exposure. Three chemical mechanisms were identified that can reduce lead release at higher flow including (1) formation of Pb(IV), (2) potential reversal of Pb:Cu couples, after which galvanic corrosion sacrifices copper and lead is protected, and (3) reduced formation of corrosive microenvironments at lead surfaces in galvanic couples. Potential reversal occurred only in the presence of free chlorine with continuous flow, and it did not occur with chloramine, with intermittent flow, or if orthophosphate was present. For both disinfectants, electrochemical measurements supported a mass balance of lead release demonstrating that a greater total mass of lead release occurred with intermittent flow than with continuous flow. [ABSTRACT FROM AUTHOR]

It has recently been proposed that lead contamination of drinking water arising from galvanic corrosion of lead and copper pipe will be minimized if the lead and copper pipes are brought into direct contact when compared to pipe separations of 1 cm to 15 cm and external electrical contact via a grounding strap. A direct, 4 month test of this hypothesis was conducted with measurement of galvanic current and lead release to water. Increased distance between lead and copper pipe, obtained by incorporating an insulating spacer between the pipes, can dramatically reduce the galvanic current and the magnitude of lead release consistent with expectations based on galvanic theory and the plumbing code. [ABSTRACT FROM AUTHOR]

Abstract: On the proper timescale, amorphous solids can flow. Solid flow can be observed macroscopically in glaciers or lead pipes, but it can also be artificially enhanced by creating defects. Ion Beam Sputtering (IBS) is a technique in which ions with energies in the 0.1–10keV range impact against a solid target inducing defect creation and dynamics, and eroding its surface leading to formation of ordered nanostructures. Despite its technological interest, a basic understanding of nanopattern formation processes occurring under IBS of amorphizable targets has not been clearly established, recent experiments on Si having largely questioned knowledge accumulated during the last two decades. A number of interfacial equations have been proposed in the past to describe these phenomena, typically by adding together different contributions coming from surface diffusion, ion sputtering or mass redistribution, etc. in a non-systematic way. Here, we exploit the general idea of solids flowing due to ion impacts in order to establish a general framework into which different mechanisms (such as viscous flow, stress, diffusion, or sputtering) can be incorporated, under generic physical conservation laws. As opposed to formulating phenomenological interfacial equations, this approach allows to assess systematically the relevance and interplay of different physical mechanisms influencing surface pattern formation by IBS. [Copyright &y& Elsevier]

The article discusses the archaeological discoveries by Manlio Lilli in Italy. It focuses on the previously unknown data of prosopographic nature, particularly the inscriptions on lead pipes (fistulae). Among the names found in lead pipes are [---]liae Calligones, Aeliae Aste, and Claudiae Aug. l. Actes. The other topics tackled include the case of the gentilicium Claudius, the senator Asellius Rufus Aemilianus, and Furius Placidus vir clarissimus.

Partial lead service line replacement with copper pipe creates a galvanic cell that can accelerate lead corrosion. Bench-scale experiments under stagnant water conditions of high chloride-to-sulfate mass ratio (CSMR) demonstrated that galvanic connections between lead pipe (new or aged) and copper pipe increased lead release into the water by 1.1 to 16 times, compared with a full length of lead pipe alone. The extent of galvanic attack was dependent on drinking water quality. Exposure to water of high CSMR increased lead release in the lead-copper rigs by 3 to 12 times, compared with a less aggressive low CSMR water. Galvanic current also increased by 1.5 to 2 times when switching from low to high CSMR. The small area of lead pipe adjacent to the copper joint (< 0.5 ft) dissipated 90-95% of the total galvanic current and accumulated a thick (1-in.-wide) layer of lead rust (i.e., a lead-containing scale), which constituted a reservoir for semirandom particulate lead detachment into the water. [ABSTRACT FROM AUTHOR]

Abstract: High lead levels in drinking water are still a concern for households serviced by lead pipes in many parts of North America and Europe. This contribution focuses on the effect of pH on lead concentrations in drinking water delivered through lead pipes. Though this has been addressed in the past, we have conducted a combined batch, pipe loop and sentinel study aiming at filling some of the gaps present in the literature. Exhumed lead pipes and water quality data from the City of London’s water distribution system were used in this study. As expected, the lead solubility of corrosion scale generally decreased as pH increased; whereas dissolution of other accumulated metals present in the corrosion scale followed a variety of trends. Moreover, dissolved arsenic and aluminum concentrations showed a strong correlation, indicating that the aluminosilicate phase present in the scale accumulates arsenic. A significant fraction of the total lead concentration in water was traced to particulate lead. Our results indicate that particulate lead is the primary contributor to total lead concentration in flowing systems, whereas particulate lead contribution to total lead concentrations for stagnated systems becomes significant only at high water pH values. [Copyright &y& Elsevier]

Computational modelling methods have been used to predict the risks from lead in drinking water across a simulated supply zone, for a range of plumbosolvency conditions and a range of extents of occurrence of houses having a lead pipe, on the basis of five risk benchmarking methods. For the worst case modelled (very high plumbosolvency and 90% houses with a lead pipe) the percentage of houses at risk in the simulated zone ranged from 34.1 to 73.3%. In contrast, for a simulated phosphate-treated zone and 10% houses with a lead pipe, the percentage of houses at risk in the simulated zone ranged from 0 to 0.4%. Methods are proposed for using computational modelling for different levels of risk assessment, for both water supply zones and individual houses. These risk assessment methods will inform policy, help to set improvement priorities and facilitate a better understanding of corrective options. [ABSTRACT FROM AUTHOR]

Destabilization of the corrosion scale present in lead pipes used in drinking water distribution systems is currently considered a major problem for municipalities serviced in part by lead pipes. Although several lead corrosion strategies have been deployed with success, a clear understanding of the chemistry of corrosion products present in the scale is needed for an effective lead control. This contribution focuses on a comprehensive characterization of the layers present in the corrosion scale formed on the inner surfaces of lead pipes used in the drinking water distribution system of the City on London, ON, Canada. Solid corrosion products were characterized using X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared (FTIR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). Toxic elements accumulated in the corrosion scale were also identified using inductively coupled plasma (ICP) spectrometry after acid digestion. Based on the XRD results, hydrocerussite was identified as the major lead crystalline corrosion phase in most of the pipes sampled, while cerussite was observed as the main crystalline component only in a few cases. Lead oxides including PbO2 and Pb3O4 were also observed in the inner layers of the corrosion scale. The presence of these highly oxidized lead species is rationalized in terms of the lead(II) carbonate phase transforming into lead(IV) oxide through an intermediate Pb3O4 (2PbIIO·PbIVO2) phase. In addition to lead corrosion products, an amorphous aluminosilicate phase was also identified in the corrosion scale. Its concentration is particularly high at the outer surface layers. Accumulation of toxic contaminants such as As, V, Sb, Cu, and Cr was observed in the corrosion scales, together with a strong correlation between arsenic accumulation and aluminum concentration. [ABSTRACT FROM AUTHOR]

The article focuses on the issues of using partial service line replacement of water pipes to decrease the lead content of water. The Centers for Disease Control and Prevention (CDC) says that new research shows that partial replacement of lead service water lines can be associated to the increased incidence of high levels of lead in the blood of children. Marc Edwards, an environmental engineer at Virginia Polytechnic Institute and State University, notes that partial service line replacement is similar to creating a source of lead dust which is delivered to every homes and is accessible of children. The 1992 report "Economics of Lead Pipe Replacement" cites that a lead pipe which is partially replaced should decrease the content of lead, however, unexpected rise of lead content occurs. INSETS: Galvanic Corrosion;Timing Is Everything.

Over 5000 public drinking water systems in the US are out of compliance with the Lead and Copper Rule. Lead leaching from lead pipes is limited by the solubility of a naturally occurring scale. Changes in water quality may cause this scale to become more soluble, releasing lead into the drinking water. We propose a novel electrochemical method to prevent lead leaching from lead pipes. In this method, an aluminum wire and an alkaline phosphate electrolyte are inserted into the pipes. The pipes are then anodized for 2 h by using an external power supply, resulting in the electrodeposition of an insoluble aluminum oxide layer on top of the preexisting scale. This technology was tested on lead pipes from the EBMUD water distribution systems located in Berkeley, CA, using recirculating synthetic and actual tap water for 120 days. The untreated pipes leached an average of 23 ppb and 38 ppb of lead respectively, when using free chlorine and monochloramine as disinfection residuals. In contrast, the treated pipes leached 3 ppb and 5 ppb respectively. These results suggest that the proposed treatment has the potential to prevent lead leaching regardless of the disinfection residual and thus should be further explored in a field trial. [Display omitted] • An electrochemical method is presented to prevent lead pipes from leaching. • This method coats insides of old lead pipes with an insoluble Aluminum oxide layer. • This treatment decreased lead leaching by 87%, compared to untreated old pipes. • Its effectiveness was independent of the water disinfectant (HOCl or NH 3 Cl). • It could rapidly provide safe drinking water until the lead pipes can be replaced. [ABSTRACT FROM AUTHOR]

Abstract: The corrosion of lead-rich pipes in historical organs in different parts of Europe has been investigated. The influence of the environment and the composition and microstructure of the pipe metal was studied. Pipe corrosion was documented by visual inspection (boroscope). The corrosion attack and the composition and microstructure of the metal were characterized by OM, SEM, XRD, IC and FAAS. It is shown that the degree of corrosion of the pipes is correlated to the concentration of gaseous acetic and formic acid in the organ. The organic acids are emitted by the wood from which the wind system is built. It is also shown that pipe corrosion decreases with increasing tin content in the range 0–4% (wt). Possible conservation strategies are discussed. [Copyright &y& Elsevier]

Lead pipes for carrying drinking water were well recognized as a cause of lead poisoning by the late 1800s in the United States. By the 1920s, many cities and towns were prohibiting or restricting their use. To combat this trend, the lead industry carried out a prolonged and effective campaign to promote the use of lead pipes. Led by the Lead Industries Association (LIA), representatives were sent to speak with plumbers' organizations, local water authorities, architects, and federal officials. The LIA also published numerous articles and books that extolled the advantages of lead over other materials and gave practical advice on the installation and repair of lead pipes. The LIA's activities over several decades therefore contributed to the present-day public health and economic cost of lead water pipes. (Am J Public Health. 2008;98:1584-1592. doi:10.2105/AJPH.2007.113555) [ABSTRACT FROM AUTHOR]

Nitrification in PVC premise plumbing is a weak function of pH over the range 6.5-8.5 and is insensitive to phosphate concentrations 5-1000 ppb. Lead pipe enhanced nitrification relative to PVC, consistent with expectations that nitrifiers could benefit from ammonia recycled from nitrate via lead corrosion. Relatively new copper pipe (<1.5 years old) did not allow nitrifiers to establish, but nitrifiers gradually colonized over a period of months in brass pipes when copper concentrations were reduced by pH adjustment or orthophosphate. Nitrifiers were inhibited by trace copper, but not by lead levels up to 8000 ppb. In some systems using chloramines, brass in plastic plumbing systems might be more susceptible to lead/copper leaching, and accelerated dezincification, due to lower pH values resulting from nitrification. [ABSTRACT FROM AUTHOR]

Dwr Cymru Welsh Water supplies over three million people with drinking water throughout most of Wales (UK). Ortho-phosphate has increasingly been dosed at around 1 mg/L (P) to further reduce the corrosivity of supplies to the lead pipes which connect approximately 30% of houses to water mains in the company's area, additional to long-establish pH adjustment measures. The installation of new orthophosphate dosing schemes and the optimisation of these and existing dosing schemes, 29 schemes in total, were subject to a regulatory programme of work, agreed with the Drinking Water Inspectorate (DWI). Optimisation comprised (i) selection of appropriate ortho-phosphate doses by a procedure involving laboratory based plumbosolvency testing linked to zonal lead emission (compliance) modelling, (ii) tight dose control and (iii) extensive monitoring of lead in supply by random daytime (RDT) sampling and by the use of lead pipe test rigs. The successful outcome was confirmed by 99% of over 5,000 RDT samples complying with the future standard of 10μg/L for lead in drinking water. [ABSTRACT FROM AUTHOR]

In 1897, about half of all American municipalities used lead pipes to distribute water. Employing data from Massachusetts, this paper compares infant death rates in cities that used lead water pipes to rates in cities that used nonlead pipes. In the average town in 1900, the use of lead pipes increased infant mortality by 25 to 50 percent. However, in cities using new pipes and distributing acidic water, lead pipes increased infant mortality three- to four-fold. Qualitative evidence supports the econometric results and indicates the adverse effects of lead extended beyond Massachusetts. [ABSTRACT FROM AUTHOR]

Tokyo Metropolitan Government has promoted measures for leakage prevention as one of our major activities. In recent years, we have been particularly targeting replacing lead pipes where leakage outbreak probability is high. In 1945, at the end of World War II, the leakage rate was about 80%. However, in 2005, the leakage rate decreased to 4.2% of the distribution water volume of 1.616 billion m³. This report describes our approach to preventing leakage. [ABSTRACT FROM AUTHOR]

Computational modelling has been used in plumbosolvency control optimisation studies involving three English water companies. A zonal model simulates lead emissions across an entire area of supply; it utilises a single pipe model that simulates the lead concentration in drinking water over a 24 h period. A sampling model then simulates the results of random daytime sampling and the results are compared with those obtained by the water company, as a means of validating the zonal model. The simulated zone is created by the random ascription of a range of variables (lead pipe length, pipe diameter, water use, pattern of flow events, etc.), based on the Monte Carlo method. The conditions of the zones that were investigated were wide ranging, and included both low and high alkalinity waters, before and after the dosing of ortho-phosphate to reduce plumbosolvency. Excellent validation was achieved, which enabled the models to be used with confidence for predictive purposes. To achieve the optimisation criteria set by the Drinking Water Inspectorate in 2001, plumbosolvency reductions of between 65 and 91% were found to be required. The minimum length of the 12 mm internal diameter lead pipe that was predicted to continue to fail the 10 μg/L standard, once phosphate dosing had been optimised, ranged from 40 to 50 m, providing a possible basis for selective replacement. Cross-referencing the zonal modelling results to laboratory treatment tests indicated that the optimum average ortho-phosphate dose varied from 0.9 to 2.0 mg/L (P), dependent on water-specific requirements. [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]