Denver Water: Accelerating Lead Service Line Replacement via BIL Funding

What is Denver Water's Lead Reduction Program?

A plan to remove every customer-owned lead service line in Denver Water's service area, and to protect customers until crews reach them.

Per Denver Water's program overview, EPA and the Colorado Department of Public Health and Environment (CDPHE) approved the program in December 2019 and again in 2022. It has three parts:

• replacing lead service lines with copper, at no direct cost to customers;
• free water pitchers, filters and replacement filters until six months after a line is replaced;
• adjusting the water's pH so less metal leaches into it.

The program runs under a federal variance. In its December 2022 announcement on the Denver Water variance, EPA says it issued the first lead variance in the country to Denver Water in 2019. It says the plan has been shown to be more effective than orthophosphate treatment.

How fast is Denver Water replacing lead lines?

About four times its earlier pace. A 2019 Denver Water article on replacing lead lines it finds says that since 2016 it had replaced roughly 1,200 service lines a year. The program target is nearly 5,000 a year.

The program's own milestones:

• At launch, Denver Water estimated 64,000 to 84,000 lead service lines and a 15-year program, per its December 2019 approval announcement.
• In 2023 it replaced 6,891 lines, for 22,325 since January 2020, per its March 2024 progress report.
• By December 2025 the total passed 35,000, per its 2025 year in review.

The job has narrowed: Denver Water's lead page now estimates 60,000 to 64,000 homes with a possible lead service line.

How did BIL funding speed up Denver Water's lead line replacement?

It paid for lines on top of the base pace. In December 2022, Denver Water accepted a low-interest Colorado Drinking Water State Revolving Fund loan, funded by the Bipartisan Infrastructure Law. Part of the principal was forgiven, per the March 2024 progress report.

The Lead Reduction Program FAQ gives the rule of thumb. Every 4,500 additional lines replaced with these funds makes the program one year shorter. When the program launched, all lead lines were slated to be removed by 2035.

In a January 2026 announcement on the state revolving fund, CDPHE lists 7,600 lead service lines replaced in Denver through Denver Water among the projects it funded.

What does the federal lead rule require of Colorado water systems?

Inventory every service line, plan the replacement, notify customers and replace lead lines within ten years. These requirements come from EPA's Lead and Copper Rule Improvements, finalized in October 2024. Community and non-transient non-community systems must comply by November 1, 2027, under 40 CFR 141.80(a)(3).

The core requirements of 40 CFR 141.84, the service line inventory and replacement section:

• Baseline inventory. Due to the state by the compliance date, and publicly accessible. Systems serving more than 50,000 people must post it online.
• Replacement plan. Also due by the compliance date. It covers how unknown lines get identified, the replacement procedure, communication and funding.
• Full replacement. All lead and galvanized requiring replacement lines under the system's control, at an average of at least 10 percent a year, done within 10 program years.
• No partial replacement. Allowed only as part of an emergency repair or in coordination with planned infrastructure work.
• Filters after replacement. A certified pitcher filter or point-of-use device, with six months of replacement cartridges.

Under 40 CFR 141.85(e), everyone served by a lead, galvanized requiring replacement or unknown line gets a notice within 30 days of the baseline inventory, and again after each annual update.

CDPHE's lead and copper rule page for water systems gives the Colorado dates. The inventory and plan are due November 1, 2027, and lead and galvanized requiring replacement lines must be gone by the end of 2037. The lead action level drops from 15 to 10 parts per billion.

Where does Colorado stand on adopting the new rule?

Colorado adopted it into Regulation 11 in August 2026. Until November 1, 2027, systems keep following the current lead and copper requirements in Regulation 11, Section 11.26, per CDPHE.

The CDPHE engagement page for the new rule says the Water Quality Control Commission adopted the rule into Regulation 11 on August 10, 2026, and the division finalized updates to Policy DW018, its service line inventory policy, in September 2026. CDPHE's rule page posts the inventory and plan forms and notice templates.

Schools and child care centers are on a separate track. The federal rule's school sampling is delayed until November 2027, but Colorado's Test and Fix Water for Kids program (HB22-1358) already requires lead sampling there, per CDPHE.

How can a Colorado water system pay for lead service line replacement?

Start with the Drinking Water State Revolving Fund. The Infrastructure Investment and Jobs Act gave the DWSRF a dedicated appropriation for lead service line work. Per EPA's October 2026 DWSRF lead service line funding playbook, 49 percent of those capitalization grants must reach disadvantaged communities as grants or forgivable loans.

Eligible uses include:

• service line inventories, even when no lead lines turn up;
• planning, design and pre-project costs tied to replacement;
• pitcher filters, point-of-use devices and tap sampling that is not for compliance;
• public outreach and education.

The DWSRF requires full replacement, main to building inlet, with limited exceptions.

In Colorado, the Colorado Water Resources and Power Development Authority, the Department of Local Affairs and CDPHE run the program jointly. More than half of the federal infrastructure money distributed so far was principal forgiveness, per CDPHE. For utilities and municipalities, a finished inventory and plan are the base a funding application builds on.

What can a smaller utility borrow from Denver Water's approach?

The sequence, not the scale. Denver Water's published steps map onto the federal rule:

• Build the inventory from property records, water tests and visual inspection, and update it as new information arrives.
• Rank work areas by exposure risk. Denver Water prioritizes areas with many facilities serving infants and children, such as schools and day care centers.
• Tell owners early. Denver Water typically sends notice a month or two before the replacement date.

Records do more of the work than digging. Our episode on service line inventories for small Colorado systems covers using assessor data and billing records first.

Is your system ready for the November 2027 lead deadlines?

Answer each question yes or no. Any no is your next task.

1. Did you file your initial service line inventory with CDPHE?
2. Do you know how many of your lines are still listed as unknown?
3. Do you have a method to identify unknowns, such as records review, customer surveys and field checks?
4. Have you started the replacement plan on CDPHE's form?
5. Are notice templates and mailing lists ready for lead, galvanized and unknown lines?
6. Do you know whether your system counts as disadvantaged for DWSRF lead funding?

Then ask your engineer: How many unknowns can records clear before we dig? Which funding cycle should the first phase target?

A note on limits: this is general education on the federal rule and Colorado's program as of October 2026. Denver Water's figures are its own, and Colorado's Regulation 11 text may differ in detail. Confirm with CDPHE.

Frequently asked questions

Does Denver Water charge homeowners to replace a lead service line?

No. It replaces customer-owned lead lines at no direct cost to the customer. A lead line found during main replacement is replaced with copper from the main to the home.

How do I know if my Denver home has a lead service line?

Start with the address lookup map on Denver Water's lead page. In its 2019 approval announcement, Denver Water said homes built before 1951 are more likely to have one.

I run a small water district in Colorado and half our service lines are still listed as unknown. What should we do before November 2027?

Work the unknowns down first. Review install dates and records, use CDPHE's customer outreach and survey templates, and check lines in the field where the records run out. Unknown lines still get a notice under the federal rule, and DWSRF money can pay for inventory work.

I'm the public works director for a small Colorado town. Can we replace only the town's side of a lead service line and leave the owner's side for later?

Not as a plan. The federal rule prohibits partial replacement unless it is part of an emergency repair or coordinated with planned infrastructure work, and then the customer gets a certified filter with six months of cartridges. DWSRF lead funding also requires full replacement, with limited exceptions.

Related resources

• Using the Texas Drinking Water State Revolving Fund (DWSRF) for Your Rural Water System
• All You Need to Know About America’s Aging Water Infrastructure Crisis
• Capital Improvement Planning for Small Municipalities: Where to Start When You Don’t Know Where to Start
• First Steps to Getting Your Project Approved with Denver Water

Planning lead service line replacement in Colorado?

MES helps small water systems turn a service line inventory into a phased replacement project and a funding-ready engineering report.

We specialize in:

• Water distribution system design
• Funding-ready engineering reports for SRF and grant programs
• Water loss and condition studies
• Capital improvement planning for small utilities
• Construction administration

Modern Engineering Solutions, McKinney, Texas. Contact: (214) 833-6748 or mod-eng.com