Lead & Copper Rule / Service Line Inventory

Our Commitment to Safe Drinking Water

Myoma Dunes Mutual Water Company (MDMWC) is committed to providing our customers with safe, reliable drinking water. As part of that commitment, MDMWC complies with the U.S. Environmental Protection Agency's Lead and Copper Rule, including the 2021 Lead and Copper Rule Revisions (LCRR), which set federal requirements for identifying and reducing lead in drinking water systems.

What Is the Lead and Copper Rule?

The Lead and Copper Rule was first established by the EPA in 1991 to limit the amount of lead and copper allowed in drinking water and to protect public health, particularly for children and pregnant women who are most vulnerable to the effects of lead exposure. In 2021, the EPA revised the rule to strengthen those protections. The revisions require every community water system in the country to complete an inventory of its water service lines and identify any that are made of lead, or that require replacement, by October 16, 2024.

A water service line is the pipe that connects the water main in the street to a customer's water meter or property line. Service lines can be made of several materials, including lead, galvanized steel, copper, or PVC. MDMWC owns and maintains the portion of the service line from the water main to the meter; the customer is responsible for the plumbing beyond the meter, including any pipes, fittings, and fixtures inside the home.

Our Lead Service Line Inventory

As required by the EPA and the California State Water Resources Control Board's Division of Drinking Water (DDW), MDMWC completed a comprehensive inventory of the water service lines throughout our system. To identify the material of every service line, MDMWC:

• Cross-referenced service line replacement and repair records
• Consulted long-tenured field and operations staff who have worked on MDMWC's distribution system
• Conducted field investigations and physical inspections of service lines and meter connections where records were incomplete
• Considered California's statewide ban on the installation of lead pipes in public water systems after 1985, which significantly reduced the likelihood of lead service lines in California systems built or expanded after that date

MDMWC submitted its initial Lead Service Line Inventory to the State Water Resources Control Board as required.

What This Means for Your Home

While MDMWC is responsible for the public portion of the water service line, homeowners are responsible for the plumbing inside their homes and on their property, including any interior pipes, solder, fittings, and fixtures. Homes built before 1986 — when Congress amended the Safe Drinking Water Act to prohibit the use of lead pipes, solder, and flux in public water systems — are more likely to contain lead-based plumbing components, which can be a source of lead in drinking water regardless of the material of the utility-owned service line.

If you are concerned that your home may have lead-containing plumbing, fixtures, or solder, MDMWC recommends the following:

• Have your interior plumbing inspected by a licensed plumber, especially if your home was built before 1986
• Run your tap for a few minutes before drinking or cooking if the water has been sitting in the pipes for several hours
• Use only cold water for drinking, cooking, and preparing baby formula, since hot water dissolves lead more easily
• Consider a water filter certified to remove lead (NSF/ANSI Standard 53) if you have concerns about your home's plumbing

Routine Testing and Monitoring

MDMWC routinely tests its water sources and distribution system for lead and copper in accordance with state and federal requirements. Our results are published in our Annual Water Quality Report, which is available to all customers, and are measured against the EPA's action levels of 15 parts per billion (ppb) for lead and 1.3 parts per million (ppm) for copper.

Public Notification

If monitoring ever shows that lead or copper levels in our system exceed the EPA's action levels, MDMWC will promptly notify affected customers and take the corrective actions required by state and federal regulations. MDMWC is committed to keeping our customers informed with accurate, up-to-date information about their drinking water.

Why It Matters

Lead can enter drinking water through the corrosion of lead-containing plumbing materials, particularly in older homes and buildings. Even low levels of lead exposure can cause serious health effects, especially in children, infants, and pregnant women. MDMWC remains committed to ongoing infrastructure improvements, routine water quality monitoring, and transparency with our customers about the safety of their drinking water.