Lead service line
A lead service line is a pipe made of lead which is used in potable water distribution to connect a water main to a user's premises.
Lead exposure is a public health hazard as it causes developmental effects in fetuses, infants, and young children. It also has other health effects in adults. According to the World Health Organization, the presence of lead service lines is the most significant contributor of lead contamination in drinking water in many countries.
The most certain way to eliminate lead exposure in drinking water from the lead service lines is to replace them with pipes made from other materials. However, replacement is time-consuming and costly. The difficulty is exacerbated in many locations by ownership structure with a shared responsibility between water utilities and property owners, which requires cooperation between the two entities. Some water utilities employ corrosion control as a short-term solution while working through long-term replacement projects. A potential issue with corrosion control is constant monitoring of its effectiveness. There have been widespread lead exposures resulting from failures of corrosion control, such as the Flint water crisis.
Background
Lead had been associated with plumbing since the ancient times. The chemical symbol for lead is derived from the Latin word plumbum, which means 'waterworks' or 'plumbing' as lead was used to make water pipes. Lead water lines have also been known to be harmful since ancient times, though this is contested by industry trade groups within the United States. Lead pipes were preferred over iron pipes because they lasted longer and were more flexible.In modern times, lead was still widely used in water distribution systems and plumbing hardware before the early 20th century, including lead pipes, leaded solder and leaded alloys. One part of the system is the connections between the water mains and the water user locations. A service line is a pipe that makes the connection, which was also made of lead in those days. The first portion of the service line is called a gooseneck, which connects to a valve at the water main and is required to be flexible to allow some movement. Lead goosenecks were commonly used in the past due to their durability and flexibility. In colder-weather areas, the connection between the water main and the rest of the service line is subjected to expansion and contraction during temperature changes. When stiffer service lines made of galvanized steel pipe were used, lead goosenecks were installed to connect to the water main to reduce breakage from such expansion and contraction.
From the mid-1800s to the early 1900s, many communities started to realize the health risks of lead and began to phase out some lead-containing products. In Australia, the use of lead service lines was restricted in the 1930s, while other countries still continued the practice of using lead service lines decades later. An example is the United States, where lead service lines were allowed until the 1980s. Not only were they allowed, but some parts of the United States mandated the use of lead service lines until 1987, primarily due to lobbying by lead manufacturers and plumbing unions. This resulted in as many as 3.3 million lead service lines and 6.4 million lead goosenecks in the country. In England and Wales, there were about 8.9 million homes with lead service lines as of 1997.
In the 2010s, one-third of American communities still had lead service lines, with an estimate of up to six million. Elimination has been extremely difficult due to the high cost of identifying, locating, removing, and preventing the many potential sources of lead in various water distribution systems in the United States.
Health effects
Lead exposure, even at low levels, can cause neurological effects, especially in young children, young women, and developing fetuses. In fetuses, lead in the mother's bones is released along with calcium during fetal bone formation. Lead can also cross the placental barrier into the fetus, which can cause premature birth, growth issues, and death of the fetus. Lead can be passed from the mother through breastfeeding. In children, the effects of lead exposure include learning problems, slow growth, and lower IQ. In adults, low-level exposure can cause hypertension, cognitive issues, and reproductive harm.Regulations
The World Health Organization published the first edition of Guidelines for Drinking-water Quality in 1984 to replace the 1970 European Standards for Drinking-Water and 1971 International Standards for Drinking-Water. The publication recommended the limits of contaminants in drinking water which set the value for lead to not more than 0.05 mg/L based on assumptions about various sources of lead intake and the provisional tolerable weekly intake of 3 mg of lead per adult that was established by the Joint FAO/WHO Expert Committee on Food Additives in 1972. However, no safe levels had been defined. In 1986, JECFA updated the provisional tolerable weekly intake level of lead for infants and children to be based on body weight, at 25 micrograms of lead per kilogram of body weight. JECFA reconfirmed this provisional tolerable value and extended the same value to all age groups in 1993. When WHO published the second edition of GDWQ in 1996, it based it on the new JECFA value assuming 50% of lead exposure from drinking water and a 5-kg infant consuming 0.75 liters of water from bottles per day, and infants are in the most sensitive subgroup. Therefore, WHO established the guideline value of lead concentration in drinking water not to exceed 0.01 mg/L.Argentina
As of early 2020 Argentina has set a standard of 0.05 mg/L based on Resolution no. 523/95-MTSS, which is an amendment of law 19587.Australia
In 2004, Australia lowered the lead exposure limit to 0.01 mg/L from 0.05 through the 2004 Australian Drinking Water Guidelines. However, this is a guideline, not a mandatory standard.European Union
On 3 November 1998, the European Union adopted Directive 98/83/EC to set standards for drinking water. This included a plan to lower the lead contamination in the water distribution systems of member states. The Directive sets the maximum lead concentration in drinking water at 0.025 mg/L by 2003, and 0.01 by 2013.A study in 1999 gave an estimate of the percentage of lead service lines in some European countries. Ireland, the United Kingdom, France, Portugal, and Belgium all had higher percentages of lead lines ranging between 15% and 51%. Germany, Spain, Italy, Luxembourg, and the Netherlands had between 3% and 9%, while Denmark and Greece had less than 1%.
Approaches to reduce lead exposure in water distribution systems to meet that goal have also differed. For example, the United Kingdom took the short- and medium-term strategy of dosing the water with orthophosphate as a corrosion-control measure and considered lead service line replacement as the long-term strategy. By 2010, 95% of public water supplies were treated with orthophosphate. The tests had 99.8% compliance with the 2003 0.025 mg/L standard and 99.0% compliance with the 2013 0.01 mg/L standard. However, many other European countries considered the practice of adding orthophosphate to the water supply to be undesirable, as it would result in sewage with higher concentrations of nutrient. That could potentially create problems of harmful algal blooms. An example of a country that took another approach was Germany. The southern part of Germany had prohibited lead pipes since the early 1900s. However, northern Germany continued to use lead pipes until the 1970s. Germany's approach to meet the new standard was to focus on the removal of lead service lines. Water utilities in northern Germany had already been working on lead service line replacements since the adoption of the Directive in order to meet the 2003 standard.
Canada
In 1992, the federal government set the guideline to have the Maximum Allowable Concentration of lead in drinking water at 0.01 mg/L. On 8 March 2019, Health Canada updated the guideline to lower the MAC of lead to 0.005 mg/L, one of the lowest values in the world. Regulation of these guidelines is performed at the provincial level, and is inconsistent.On 4 November 2019, Concordia University published a year-long study which found that one-third of water samples from 11 major Canadian cities tested higher for MAC of lead than the national guideline, with the highest levels recorded from samples in Montreal, Prince Rupert, and Regina. It was also found that some municipalities only had estimates on the number of lead service lines still in use, with no exact data available.
United States
The "Lead and Copper Rule Improvements" regulation, issued by the United States Environmental Protection Agency in October 2024, specifies an "action level" for lead at 0.010 mg/L. A public water system is required to monitor its water supply at customer locations. If more than 10% of tap water samples exceed the lead action level, the supplier must take additional steps to control corrosion. Other actions may include installation of treatment, checking of source water, removal of lead-containing plumbing, and public education. The 2024 regulation also requires public water systems to remove all lead pipes within ten years.Uruguay
Uruguay set the lead exposure of drinking water to 0.05 mg/L in 2000 through Decree 315/94, 2nd edition. It also banned lead water pipes and fittings in 2004. The country set new standards in 2011 through Decree 375/11 to lowered exposure level to 0.03 mg/L and to achieve 0.01 mg/L level by 2021.Replacements
Responsibilities
There are two parts in a service line. The first part is the pipe that connects the water main to the curb stop which is a stop valve that is located around the street curb or the property line. That first section is called communication pipe. The second part is the pipe that connects the curb stop to the building inlet or a water meter. This part is called supply pipe. Depending on local water utilities, the meter may be located at the property line instead. When the water meter is located at that alternative position, the pipe section that connects the water main to the water meter is the communication pipe, and the section that connects the water meter to the building isolation valve is the supply pipe. Lead service lines can exist in one of these scenarios: the communication pipe section can be made of lead, called the lead communication pipe; the supply pipe section can be made of lead, called the lead supply pipe; the entire length can be made out of lead; or only a small section of the communication pipe at the water main is made out of lead.The ownership structure of service lines varies among water utilities. Depending on localities, the entire length of a service line from the water main to the building inlet may be owned by the water utility, or the property owner. There can also be a partial ownership scenario where the water utility and the property owner share ownership of the service line, thus, replacing the entire lead service line requires a cooperation between the two entities. In the shared ownership, the water utility typically owns the communication pipe and the curb stop, and property owner owns the supply pipe. In this scenario, when the water utility owned section of a lead service line is called public lead service line, and the section owned by the property owner is called private lead service line. When only one part of a lead service line is replaced, it is called partial lead service line replacement. When both sides are replaced at the same time, it is called full lead service line replacement.
Where there is involvement with private ownership, it complicates a full lead service line replacement. A major issue is the cost of the replacement. In the United States, a replacement can cost between $3,000 to $5,000 for the private side. This can be a major financial burden for homeowners. Even with incentives such as interest-free loans, or using ratepayer money to cover part of the cost, homeowners are still hesitant. Using ratepayer money to fund private lead service line replacements in itself is a subject of debate. Those who advocate for it argue that the benefits to public health outweigh a small increase in water rates that impacts everyone. On the other side, there is a concern that the increased rates can cause hardship, and there is a public policy question on using ratepayer money to make private property improvements.
Even in the case that private lead service line replacements are fully funded at no cost to property owners, some owners still refuse to allow their water utility to do work on their property for various reasons, such as fearing property damage or not wanting workers inside. For example, in Pittsburgh, 10% of property owners refused no-cost replacement of private lead service lines. This problem is exacerbated in rental properties where tenants have no authority to accept the offer, and landlords do not see the value of the investment. For cities with a large amount of renters, it is difficult to complete a full lead service line replacement program without any forms of mandate through a local ordinance. Alternately, some common law jurisdictions may have enough legal precedent in regard to public nuisance law. Courts may allow municipalities to access private property to address the public health threat without having to obtain permission from the property owner.