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Distribution system materials inventory (DSMI)

Distribution system materials inventory (DSMI)

Michigan water supplies must maintain an inventory of service line materials in their distribution systems. By January 1, 2020, public water supplies were required to submit a preliminary distribution system materials inventory (PDSMI). By October 16, 2024, water supplies must have developed and submitted a complete distribution system materials inventory (CDSMI) to EGLE.

DSMI timeline

January 1, 2020

Preliminary distribution system materials inventory (PDSMI)

Completed by January 1, 2020, the primary focus of the preliminary DSMI was for water supplies to review their existing records and report what is known and unknown regarding service line materials.

Interim step

Minimum service line verification

As an interim step between the PDSMI and the CDSMI, a representative, uniformly random number of service lines was physically verified to effectively evaluate the accuracy of service line records and/or predict service line materials.

October 16, 2024

Complete distribution system materials inventory (CDSMI)

Water supplies must have developed and submitted to EGLE a CDSMI by October 16, 2024. The CDSMI is to characterize, record, and maintain a comprehensive inventory of distribution system materials, including service line materials on both public and private property.

 

Periodically

Update to CDSMI

Water supplies are required to periodically update and resubmit the CDSMI to EGLE.

Training webinars for DSMI

  • Improving Lead and Copper Sample Plans, Service Line Inventories, and Sample Reports, Part 1 (3/4/26, 1 hour)

    This two-part webinar series discusses how community water supply lead and copper sample plans, service line inventories, and sample reports are inter-related. New guidance and a voluntary checklist will be shared to assist operators with improving the alignment of these documents. EGLE will also present proactive approaches to address unknown service lines, share reminders for service line material notifications to customers served by a lead, galvanized previously connected to lead, and lead status unknown service lines, and how to voluntarily update service line inventories before the next regulatory deadline.

  • Improving Lead and Copper Sample Plans, Service Line Inventories, and Sample Reports, Part 2 (3/5/26, 1 hour)

    This two-part webinar series discusses how community water supply lead and copper sample plans, service line inventories, and sample reports are inter-related. New guidance and a voluntary checklist will be shared to assist operators with improving the alignment of these documents. EGLE will also present proactive approaches to address unknown service lines, share reminders for service line material notifications to customers served by a lead, galvanized previously connected to lead, and lead status unknown service lines, and how to voluntarily update service line inventories before the next regulatory deadline.

  • CDSMI Final Submittal (3/13/2024)

    This webinar provides an overview of the entire DSMI process with a focus on completing the final steps and submitting the documents, including how to complete the CDSMI Summary Form and the CDSMI Line-by-line Inventory. This webinar also includes how systems should submit the Complete DSMI to EGLE.

  • Evaluating Minimum Service Lines Material Verification Data (3/22/2023)

    This webinar provides an overview on how to evaluate the data collected during the minimum service line physical verification step of the DSMI process. It also details how to use existing records and recently field verified data to reliably classify service line materials for the entire distribution system.

  • Overview of Service Line Replacement and CDSMI-Minimum Services Line Material Verification Requirements (9/13/2022)

    This webinar provides an overview of what is required when completing service line replacement and what steps should be taken when working to complete a DSMI. This webinar details the minimum expectation for physical verification of service lines in a system, which includes how many randomly selected service lines need to be verified and how to randomly select those service lines.