Water System Resources

Division of Drinking Water (DDW) Inventory Submission

A WBKey account is required to submit an Initial LSLI on the portal and one account per water system is recommended. Systems may also email their inventory to the LCR Unit for review and approval.

• Initial LSLI Submission Portal (ca.gov)
• Initial LSLI Portal User Guidance Document
• DDW-LCR@waterboards.ca.gov

DDW Inventory Guidance

Each community and non-transient non-community water system must maintain the required inventory information described in the FAQ and inventory instructions below.

• LCRR Inventory FAQ (updated Jul 2025)
• LCRR Inventory Methods (updated Dec 2023)
• LCRR Inventory Instructions (updated Jul 2025)

DDW Inventory Templates

DDW’s inventory template covers the minimum information required for LCRR compliance.  DDW recommends that water systems use one of the templates provided below or at least follow this format when developing their inventory to ensure effective data transfer into the portal. If you have compatibility issues with Excel or need a template for over 50,000 service lines, please contact the LCR Unit.

• Inventory Template - Up to 100 Service Lines
• Inventory Template - Up to 5,000 Service Lines
• Inventory Template - Up to 50,000 Service Lines

DDW LCRR Training Videos

• LSLI - Overview Video (Jul 2024)
• LSLI - Overview PDF (Jul 2024)
• LSLI - Small Systems Video (Sep 2024)
• LSLI - Small Systems PDF (Sep 2024)
• LCRR - Part 1: Overview
• LCRR - Part 2: Starting the Private Side Inventory
• LCRR - Using the DDW Inventory Template

Other Inventory Resources

• US EPA Guide for Developing and Maintaining a Service Line Inventory (Aug 2022)
• US EPA Guide for Developing and Maintaining a Service Line Inventory for Small Entity Compliance (Jun 2023)
• ASDWA Lead Service Line Symposium (Feb 2022)
• ASDWA Initial LSLI Lessons and Information Gaps Webinar (Oct 2023)
• ASDWA papers, communications, webinars, and resources for the LCRR

Summary of Inventories

*Typically, this is the utility-owned portion which includes the pipe, tubing, and fittings connecting a water main to an individual water meter or service connection.

SB427 Lead Service Line Requirement

Resources for lead service line inventory and replacement under Senate Bill No. 427 (SB427) are available at the Lead Service Line Replacement Collaborative website. For more information, please visit the Health and Safety Code 116885 User Service Line Inventory page.

Public Notification Templates

90th Percentile Lead Action Level Exceedance (Tier 1)
All community and non-transient non-community water systems are required to issue a Tier 1 public notice within 24 hours after discovering a 90th percentile lead action level exceedance (ALE) starting October 16, 2024. (40 CFR 141.202(a)(10)).  See the standard operating procedure below for instructions on what to do if your system has a 90th lead ALE.

• PN Standard Operating Procedure - Lead ALE
• PN Template - Lead ALE (English)
• PN Template - Lead ALE (Spanish)
• PN Certification - Lead ALE

Failure to Complete an Initial Inventory by October 16, 2024 (Tier 2/Tier 3)

Water systems that fail to develop an initial service line inventory by 10/16/2024 must provide Tier 2 public notice to its customers within 30 days. Systems that fail to submit an inventory by the deadline must provide Tier 3 public notice to its customers or include the Tier 3 notice in their Consumer Confidence Report (CCR) for that year (40 CFR 141.203, 40 CFR Appendix A to Subpart Q – I.C.1).

• PN Template - Failure to Complete Initial Inventory
• PN Template - Failure to Complete Initial Inventory (Spanish)
• PN Certification - Failure to Complete Initial Inventory

Notification for Lead, GRR, and/or Unknown Service lines

Pursuant to 40 CFR 141.85(e), water systems with known or potential service lines containing lead must provide public notice to all persons served by lead, galvanized requiring replacement (GRR) and/or lead status unknown (unknown) service lines. The first notification must be posted by November 15, 2024, and repeated annually until the service line is classified as non-lead. Notifications must be certified to DDW by July 1 of the following calendar year.

• PN Template - Lead Service Lines
• PN Template - GRR Service Lines
• PN Template - Unknown Service Lines
• PN Template - Lead, GRR, or Unknown Service lines (Spanish)
• PN Certification - Systems with Lead, GRR, and/or Unknown Service Lines

Inventory Public Accessibility

Water systems must make their lead service line inventory publicly accessible. For systems serving over 50,000 persons, inventories must be accessible online.

Water systems with only non-lead service lines in their inventory may provide a written statement instead of a publicly accessible inventory. The written statement must include a general description of the methods used to determine service line materials as noted in the templates below.

• Non-lead Statement Template - All Service Lines Verified
• Non-lead Statement Template - Stratified Random Sampling
• Non-lead Statement Template - Interpolation
• Non-lead Statement Template - Interpolation, Systems with Less Than 1,500 Services
• Non-lead Statement Template - Other Method(s) Used

Consumer Confidence Reports (CCR)

Public water systems are required to provide information to their customers and consumers about the quality of their drinking water in their CCR. Updates to the mandatory lead and copper health effects language in the CCR will be required under the LCRR and LCRI. Instructions to access the service line inventory or the non-lead statement must be included in water systems’ annual CCR.

Implementing the Lead Public Education Provision

• US EPA LCR Public Education Guide for Community Water Systems
• US EPA LCR Public Education Guide for Non-Transient Non-Community Water Systems

Under both the LCR and LCRI, water systems are required to periodically obtain tap samples for lead and copper testing. Systems that have a 90th percentile lead action level exceedance (ALE) must notify DDW, US EPA, and all consumers within 24 hours of discovery. Below are guidelines and forms to assist with 90th percentile level calculation and reporting to meet current LCR requirements.

• DDW LCR Tap Sampling Guidance Document
• DDW LCR Tap Sampling Reporting Form
• DDW LCR Tap Sampling Site Change Form
• US EPA memo clarifying recommended tap sampling procedures for the LCR
• US EPA Suggested Homeowners Tap Sample Procedures