Update on Baltimore City’s Water Service Line Inventory

Notification Letters to Residents Begin This Fall

The Baltimore City Department of Public Works (DPW) announced today that notification letters will soon be mailed to Baltimore residents and businesses whose properties are known or predicted to have water service lines that are made of lead or galvanized pipe. Customers with service lines made of unknown pipe material will also receive letters urging them to complete DPW’s online Self-Reporting Survey.

These notifications are part of DPW’s ongoing effort to update and improve the City’s water service line inventory, which is being developed in accordance with the U.S. Environmental Protection Agency’s Lead and Copper Rule Revisions (LCRR).

Since the initial inventory was completed in October 2024, DPW has made significant progress identifying lead and galvanized service lines and continues to expand the accuracy of its records through field investigations, predictive modeling, and advanced detection tools.

Inventory Snapshot – September 2025

• Lead service lines identified: 9,193 (2% of all service lines)
• Galvanized requiring replacement (GRR): 459 (0.1% of all service lines)
• Service lines with unknown material: 58,508 (13% of all service lines)

DPW is using predictive modeling and state-of-the art technology to estimate the material of water service lines without excavation. These tools allow DPW to minimize disturbances to property owners and reduce costs. Together, these tools have helped DPW classify more than 150,000 service lines to date, saving the City more than $105 million in costs.

DPW is leveraging cutting-edge technology that uses a low-voltage conductivity probe to locate lead pipes without excavation. Predictive modeling uses machine-learning algorithms to analyze demographic, geographic, and historical data to identify trends that indicate the presence of lead or non-lead service lines.

Next Step: Customer Notification Letters

In the coming weeks, DPW will begin mailing letters to customers whose properties are known or predicted to have water service lines that are made of lead or galvanized requiring replacement (GRR) pipe. These letters will provide:

• Confirmation of the service line material at the property
• Steps residents can take to reduce exposure to lead in drinking water

Additionally, customers with unknown service line materials will receive letters urging them to complete DPW’s online Self-Reporting Survey to help improve the accuracy of the City’s records.

How Residents Can Help

DPW is asking all Baltimore water customers who have not already done so to complete the City’s Self-Reporting Survey:

1. Visit www.servicelinepartnership.baltimorecity.gov
2. Click the Take the Self-Reporting Survey! button
3. Enter your address
4. If a blue dot appears at your property, complete the short survey and upload a photo of your service line, if possible

More Information

For the full inventory or answers to frequently asked questions, visit the Baltimore Service Line Partnership website.