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Alameda County, CA, acgov.org

April Williamson
Interim Deputy Director
Healthy Homes Department
Including the Lead Poisoning Prevention Program

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Possible Sources of Lead


soucres of lead in water

The EPA estimates that drinking water accounts for about 20% of our lead intake nationally. For some people, it can be the biggest source of lead exposure. But the problem of lead in water varies significantly throughout the United States. While it may pose a great hazard in Boston; Alameda County's water is relatively lead free.

How does lead get into drinking water?

Lead can enter drinking water when plumbing materials that contain lead corrode, especially where the water has high acidity or low mineral content that corrodes pipes and fixtures. The most common sources of lead in drinking water are lead pipes, faucets, and fixtures. In homes with lead pipes that connect the home to the water main, also known as lead services lines, these pipes are typically the most significant source of lead in the water. Lead pipes are more likely to be found in older cities and homes built before 1986. Among homes without lead service lines, the most common problem is with brass or chrome-plated brass faucets and plumbing with lead solder.

Source: Environmental Protection Agency

How does the country protect its drinking water?

The Safe Drinking Water Act (SDWA) was originally passed by Congress in 1974 to protect public health by regulating the nation's public drinking water supply. The law was amended in 1986 and 1996 and requires many actions to protect drinking water and its sources-rivers, lakes, reservoirs, springs, and ground water wells. SDWA authorizes the United States Environmental Protection Agency (US EPA) to set national health-based standards for drinking water to protect against both naturally-occurring and man-made contaminants that may be found in drinking water. US EPA, states, and water systems then work together to make sure that these standards are met.

The Safe Water Drinking Act, originally passed by Congress in 1974, requires that only "lead-free" pipe, solder or flux may be used in the installation or repair of (1) public water systems or (2) any plumbing in a residential or non-residential facility that is connected to a public water system and provides water for human consumption. "Lead free,"" as defined in the SDWA, means that the maximum allowed concentration is

  • 0.2 percent in solder and flux;
  • 8.0 percent in pipes and pipe fittings;
  • 4.0 percent lead by dry weight in plumbing fittings and fixtures.

In addition to the 8.0 percent limitation on lead content, certain plumbing fittings and fixtures must meet with standards established in accordance with section 1417(e) of the SDWA. As discussed further below, federal law requires that plumbing fittings and fixtures must comply with the standards contained in NSF Standard 61, section 9.

Source: Department of Toxic Substances Control & Environmental Protection Agency

How does California protect its drinking water?

In addition to the federal regulations for drinking water safety, California has further defined "lead free" to mean that the maximum allowed lead content is:

  • 0.2 percent lead in solder and flux;
  • 0.25 percent lead in wetted surfaces of pipes, pipe fittings, plumbing fittings and fixtures, as determined by a weighted average.

The new California law further prohibits:

  • Any person from using any pipe, pipe or plumbing fitting or fixture, solder, or flux that is not "lead free" in the installation or repair of any public water system or any plumbing in a facility providing water for human consumption, except when necessary for repair of leaded joints of cast iron pipes;
  • Any person from introducing into commerce any pipe, pipe or plumbing fitting, or fixture that is not "lead free," except for a pipe that is used in manufacturing or industrial processing;
  • Any person engaged in the business of selling plumbing supplies, except manufacturers, from selling solder or flux in the business that is not "lead free;"
  • Any person from introducing into commerce any solder or flux that is not "lead free" unless the solder or flux has a label stating that it is illegal to use solder or flux in the installation or repair of any plumbing providing water for human consumption.

Source: Department of Toxic Substances Control

Risk factors

The amount of lead that is dissolved into the water is affected by the water's acidity, hardness, and temperature. Water in the eastern United States is typically more acidic and softer than water on the West Coast. Therefore, Alameda County's water is less likely to leach lead from pipes and solder. Water that has a high concentration of minerals is called hard water. The minerals in hard water eventually coat the inside of the pipes and prevent lead from dissolving into the water. More lead is leached out of pipes and solder when the water stays in pipes a long time, and when the water is acidic, soft, and hot. Alameda County's water is hard, as it contains higher levels of minerals.

Lead service line replacement

Water service lines are the pipes and joints (also known as "fittings") that connect the plumbing in your home to the water main under the street. Service lines that contain lead are called lead service lines. California public water utilities are replacing lead service lines that they own (i.e., the section that runs from the water main to your water meter) over the next ten years. Water utilities are not responsible for replacing private service lines owned by the homeowner or customers served by private wells. Check if your local water utility has a lead service line replacement (LSLR) timeline, and where and when it will happen on the California Water Boards' LSLR Status Map Update (Excel spreadsheet will appear as a downloaded file from your internet browser). The lead service line replacement process may be changing in California.

Source: California Department of Public Health

Are lead pipes an issue in Alameda County?

Lead pipes are generally found only in homes built before 1930. However, EBMUD began a program years ago of replacing lead service lines installed during WWII. As of 1992, roughly 900 of these lines (0.003% of the district's total) remained in service, but all are scheduled to be replaced over the next 10 years as part of the state's lead service line replacement.

Testing water for lead

The only way to really know if a home has high lead levels in the drinking water is to test the water. Testing for lead in drinking water typically consists of collecting two samples. The first is called a first draw sample. It is collected immediately when the water is turned on after having been off for an extended period of time, usually overnight. If the results of this sample is high, it indicates that lead is leaching from lines within the building.

The second sample is a purged line sample which is collected after the tap has run for one minute to clear the water in the lines. This sample normally shows the amount of lead in water from a source outside the house - typically from the service line. It usually has a low lead level. If the purged-line samples show a lead count of more than 5 ppb, there may be lead in the service line.

To find out if the service line contains lead, the water utility or a licensed plumber would need to inspect the service line. Homeowners may legally own some or all of the service line and if they choose to have it replaced, they may have to pay at least part of the replacement costs.

What to do

If the water has not been tested, or if it has been found to contain lead levels of more than 15 ppb, then there are several things that can be done to reduce ingestion of lead from drinking water.

  1. Do not drink, cook, or make baby formula with water from the hot water tap.
  2. If the cold water hasn't been used for more than two hours, run the tap for a few minutes before drinking it or using it for cooking. (This water can be saved for watering plants).
  3. To conserve water, or if you don't want to flush the lines often, you can keep a jug of flushed water in the refrigerator.
  4. Consider buying a filter certified for lead removal (although, this is not usually necessary in Alameda County), or drink bottled water.
  5. When lead levels are high, if possible, you may need to replace the plumbing or service line, or lead containing faucets.

Boiling the water will not reduce the amount of lead. Also realize that bathing is not a problem because lead does not enter the body through the skin.

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