Should I Use Copper or Plastic Pipe for My Lead Service Line Replacements?
As water utilities ramp up their lead service line replacement programs to meet new requirements under the Lead and Copper Rule Improvements, this question has become increasingly common. The following provides key insights and summary information to guide your decision-making.
Is copper or polyethylene (PE) pipe a better long-term investment for my water system?
The cost of replacement pipe often represents a significant portion of lead service line replacement construction costs. It’s logical for pipe materials to be one of the largest line-item expenses in a service line replacement.
When considering material costs, replacing lead with plastic pipe may include an additional expense: properly grounding the building’s electrical system if it was previously grounded to the lead pipe. The American Water Works Association (AWWA) opposes the grounding of electric systems to water service lines and recognizes the need to properly ground a home’s electrical system when replacing lead service lines with nonmetallic pipe (AWWA 2017; 2024).
Compared to PE, copper pipe increases the cost of a lead service line replacement by $670 for a single short-side replacement (where the water main is on the same side of the street as the building and the new service line does not cross the street), and $1,200 more for a long-side replacement (where the service line must cross the street). Although these costs were consistent for 2024, copper prices are now volatile due to tariff uncertainty.
Figure 1: Cost of Replacing 1,000 Lead Service Lines Using Directional Drilling with Copper or Polyethylene (PE)
From a lifecycle perspective, copper service lines are estimated to last twice as long as PE pipes, which can double or triple the long-term cost of PE service line replacements over extended time horizons. This is demonstrated in Figure 1.
Figure 1 illustrates the cost considerations using a hypothetical small to medium water system that must replace 1,000 lead service lines. Figure 1 shows that the first-year cost of replacing 1,000 pipes with PE may save $900,000 compared to copper, but making the upfront investment in copper may save $2.2 million over the life cycle of the new service lines. Cost is one of several considerations when selecting a material for replacing lead service lines.
What other factors should I consider when selecting pipe material for my lead service line replacements?
In addition to longer life span and lower life cycle cost shown in Figure 1, Table 1 presents additional benefits of copper compared to PE pipe:
Only one compound of health concern; it is already regulated with mandatory tap sampling
High resistance to extreme heat, particularly wildfires
Low risk for permeation in flooding and chemical spill environments
A history of research and documentation of durability and health impact
It is important to note the lack of sampling and research at the tap for contaminants related to PE pipe. Replacing lead service lines with a material with a high potential for not yet documented risk may create a public health based need for PE pipe replacement and further water utility costs in the future.
According to Table 1 there are some conditions in which PE pipe might have important advantages that should be taken into consideration:
Corrosive water or soil
High and frequent earthquake risk
Table 1: Summary of Material Considerations for Copper and PE Pipe1
| Consideration | Copper | Polyethylene (PE) |
|---|---|---|
| Corrosion Resistance1 | High in general, but low in comparison to plastics Greater risk in corrosive water and soil |
High resistance |
| Service Life1,2 | 50-100 years | 20-50 years, up to 100 for HDPE |
| Electrical Grounding3 | Not required | New grounding is required, adding $265 to the material cost of a PE replacement.4 |
| Compounds of Health Concern1 | Copper, both an essential micronutrient and a potential toxic metal | • Organotin Compounds (e.g., dimethyltin, butyltin, tributyltin) • Antioxidants including 2,6-di-tert-butyl-4-methylphenol (BHT) • Phenolic compounds • Tert-butyl methyl ether (MTBE) • Disinfection Byproducts (TTHM and HAA5) • Microplastics |
| Sampling Requirements and Regulatory Limits for Compounds of Health Concern5 | EPA Action Level: 1.3 mg/L Sampling currently required at the tap, but sample sites do not target high copper risk locations |
None No sampling required at the tap |
| Extreme Heat (e.g., wildfires)1 |
High Resistance | Low to Medium Resistance; increased leaching of compounds of concern |
| Permeation1 | Low risk limited to gaskets | Susceptible, more than PVC Increased risk with flood and chemical spills |
| Earthquake Resistance1 | Subject to breakage at joints | More flexible but breakage still possible |
| Depth of research1 | Well studied | Specific materials used continue to evolve; new materials not well documented and very limited research on long term impact |
Sources:
1 (Proctor et al. 2024)
2 (Lee et al. 2017)
3 (AWWA 2017)
4 (RS Means 2024)
5 (EPA 2024)How can I achieve the greatest construction cost savings? Can I offset the up front cost of copper?
As discussed in the full report, the largest factor influencing construction costs is the amount of paved surface that is disturbed, coupled with the restoration needed and/or required. As shown in Figure 2, switching from open trench to directional drilling for a long-side replacement can save around $1,500. The cost difference is much smaller for a short-side replacement where a smaller amount of paved surface is disturbed.
Figure 2: Independent Full Lead Service Line Replacement Construction Cost Estimates comparing Open Trench with Directional Drilling Methods1, 2
1 The PE replacement cost has been updated here to include the cost of electrical grounding compared to the full report.
2 The low unit cost values in the independent construction cost estimates indicate that several auxiliary costs are included in commonly reported lead service line replacement costs summarized in the full report.
For more information on planning strategies and costs of lead service line replacement programs, consult the full report, “Lead Service Line Replacement Costs and Strategies for Reducing Them,” published in February 2024.
References
AWWA (American Water Works Association). Last Updated September 9, 2024. “Grounding of Electrical Circuits on Water Pipe.” https://www.awwa.org/policy-statement/grounding-of-electrical-circuits-on-water-pipe.
AWWA C810-17 Replacement and Flushing of Lead Service Lines.
EPA (Environmental Protection Agency). Updated December 2024. “National Primary Drinking Water Regulations. https://www.epa.gov/ground-water-and-drinking-water/national-primary-drinking-water-regulations.
Lee, Juneseok, and Myles Meehan. 2017. “Survival Analysis of US Water Service Lines Utilizing a Nationwide Failure Data Set.” Journal American Water Works Association 109 (9): 13–21. https://doi.org/10.5942/jawwa.2017.109.0098.
Proctor, C., Ehde, A., Haque, A. 2024. “Lead Service Line Replacement: Material Considerations and Impacts.” Presentation to the Lead Service Line Replacement Collaborative on October 25, 2024.
RS Means. 2024. “Online Construction Cost Database.” www.rsmeans.com.
