Water utilities
Principle 1
Optimize Inventories and Data Collection
Define the scope of the problem by locating and documenting lead pipes in your system.
Key Actions
Key Action 1
Improve data collection and data management
An important early step for every utility is to develop an initial inventory of the material types of each service line in the distribution system. This process begins with a review of available historical records such as tap cards and construction documents.
To build a more complete and effective service line inventory, utilities can take several key actions:
Digitize historical documents
Digitize historical documents to convert old paper records of lead service lines into digital files that can be quickly referenced by current and future staff. External contractors can support digitization efforts. Utilities will need to consider how reliable these records are and weigh the cost of the digitization effort against the expected benefit of the information that can be extracted from historical documents.
Digitize and geolocate inventory data
Summarize inventory data in a digital platform with capabilities to geolocate information. Utilities can leverage geographical information systems (GIS) that are typically used for tracking other utility assets (e.g., linear assets, piping, valves) and can be used in system mapping for public-facing inventories. For some utilities, this lead service line replacement (LSLR) effort may be the first implementation of a GIS system; however, once established, it can be leveraged for future asset management.
Collect available digital data
Collect available digital data to get an initial understanding of what information is readily available to build your inventory. This information can include billing meter installations, utility service line replacement and repair records, and other relevant data.
Assess data quality
Assess the quality of the data to determine how much additional time and resources are needed to refine the data at the program onset rather than improving information as the program progresses. Water utilities should follow best practices outlined by EPA, keeping in mind that states may have different requirements for data quality assurance and quality control (QA/QC).
Collect additional asset data
To maximize efficiencies, collect additional asset data during service line replacements. When staff are on-site to evaluate service line materials, it’s a valuable opportunity to document information on other system components – such as meters and valves – and update asset management records. Conversely, service line materials can be assessed during other routine utility workflows.
Toolbox
Inventory mapping
Inventory templates
Key Action 2
Engage the community and volunteers to identify the material type
Conducting a service line inventory is costly and labor-intensive, especially with many unknowns. While various inspection methods exist, all require funding and potential contractor support. To lower costs and minimize rate impacts, utilities can engage community leaders to encourage resident participation in service line identification.
Utilities should consider the following actions for customer identification:
Engage city officials, community leaders, and nonprofits
Engage city officials, community leaders, and non-profits in the outreach process to increase the visibility of the lead service line inventory (LSLI) project and show the importance of LSL replacements to your utility. Non-profits working in the health and child welfare space may be uniquely positioned to support efforts.
Provide step-by-step instructions to residents
Provide detailed instructions to residents on how to properly identify the water service line and how to distinguish between different service line materials. Instructions should include performing a scratch test and magnet check, along with photos as part of the instructions to customers.
Provide an online portal
Provide an online portal to allow customers to easily upload the results of their inspection and supporting documentation to confirm results are accurate. It is recommended that customers upload photos of their water service line showing where they scratched it and performed the magnet test. These photos should be reviewed by someone who has received training to confirm the customer’s report.
Consider incentivizing residents
Consider incentivizing residents through gift cards or credits to their water bill. Despite research by EPA showing that the efficacy of incentives to increase program participation may not be strong, some utilities report that incentives can be useful. The effectiveness of this strategy will vary by community. Utilities may need to check if there are any restrictions on the use of rate revenues to provide customer incentives.
Increase accuracy of results
Increase accuracy of results by requiring documentation such as photos or videos. Utilities have reported varying degrees of success and accuracy with resident self-reported inspections; however, requiring visual documentation can increase reliability significantly.
Before updating the service line material inventory, a quality assurance and quality control (QA/QC) step for the customer-submitted information should be built in. This QA/QC process could include visual confirmation by city staff, trained volunteers, or contract professionals.
In addition, it is highly recommended that utilities follow up on every self-report. Follow-ups may include confirming receipt of the submission, providing next steps (such as signing up for a lead service line replacement), requesting additional information, or scheduling an appointment for an inspection or a replacement. Platforms that can collect photos or videos may assist utilities in collecting and collating customer-captured media.
Combine customer self-reporting with door-to-door canvassing
Consider pairing customer outreach efforts with a door-to-door canvassing campaign or appointment system to boost participation and strengthen relationships with residents. Local non-profits or interns can be trained to serve as inspectors and utility ambassadors, helping to educate the community, answer questions, and collect needed information while building local capacity and trust.
Toolbox
Engaging volunteers in door-knocking campaigns
Customer guidance for self-reporting of service line materials
Inventory management tools
Key Action 3
Close inventory data gaps with physical inspections and predictive analysis
Historical records often fall short in identifying service line materials, requiring utilities to inspect homes individually. Options range from costly physical inspections to emerging predictive modeling and alternative methods, which offer potential savings but may still be under development.
Find the right physical inspection method
Find the right physical inspection method for you. Best practices for physical inspections can be classified based on their level of intervention:
Non-invasive methods
Non-invasive methods rely on inspecting the pipe in its current condition without digging or direct access to buried pipes. These methods are often the easiest and most efficient. For example:
- “Daylights” consists of inspecting the outside of the pipe where it is currently exposed (“daylights”).
- Non-excavation methods that use technologies to detect the pipe such as ground penetrating radar, acoustic methods, and metal detection.
Invasive methods
Invasive methods require exposing the pipe where it is buried underground by removing soil, grass, or pavement or entering the pipe itself.
- Excavation methods expose a section of the service line so that it can be visually inspected or tested for material type. Potholing or hydro excavation (AKA hydrovacing) are among the most commonly used excavation methods.
- In-pipe inspection methods consist of inserting a device into the service line at an access point near the meter connection.
Engage the community to complete inventories
Engage the community to perform service line surveys and scratch tests. Utilities can effectively engage the public to assist in service line inspections by enabling residents to inspect their own service line materials. See: Principle 3, Key Action 2 for more information on how to do this effectively.
Leverage non-invasive solutions
The following methods are typically referred to as “non-invasive” approaches for service line inspection as they do not require excavation of the lead service line.
Meter and visual pipe inspections
Meter and visual pipe inspections help assess service line material at connection points near the meter or within the residence when the meter is inside the home. While informative, these inspections may not represent the entire line as only a portion of the line may have been replaced during a previous repair. Additionally, inspecting meters inside the home requires homeowner coordination, which can be time-consuming.
Water Quality Analysis
Water Quality Analysis is often used as a supporting method for identifying the presence of lead pipes. Water quality testing for lead can be limited depending on water treatment and the use of a corrosion inhibitor; therefore, it cannot be reliably used to confirm the absence of lead. Methods are provided by EPA.
Ground Penetrating Radar
Ground Penetrating Radar can be a way to identify lead service lines without excavating; however, the accuracy of this method will vary.
Direct Contact X-ray Fluorescence (XRF)
Direct Contact X-ray Fluorescence (XRF) is the only exterior method that can detect lead-lining inside pipes. Historically, galvanized pipes were lined with lead to improve their lifespan. These types of pipes were used in water systems across the country from the late 1800s to at least the 1960s and are indistinguishable from unlined galvanized pipes with other exterior inspection methods. XRF devices designed for metal pipes read the composition of the pipe material across the depth of the pipe’s inner and outer rings. These devices must touch the surface of the pipe to make the reading. So excavation or access to pipes inside homes is necessary. Detections of lead by XRF may indicate a build-up of lead scale or lead lining, both of which are of concern and merit pipe replacement. An individual XRF unit can cost approximately $25,000.
Remote XRF
Remote XRF is a device that can read the composition of pipes through the ground surface. Since EPA is currently piloting this method, the results of this study and the conditions under which it could be used need further review.
Metal detection
Metal detection can be useful for areas where the water pipes are more shallow. Metal detectors may be useful for distinguishing metal pipes from plastic water pipes, reducing the amount of excavations needed. Some metal detectors can even determine the type of metal below ground. Utilities should ensure metal curb boxes do not interfere with pipe detection and test the accuracy of metal detectors before large-scale use.
Utilize excavation technologies
Utilize excavation technologies to visually confirm the material type. In situations where the service line is not readily accessible, utilities often consider some form of excavation to uncover the pipe and allow staff or contractors to visually inspect the service line. It should be noted that these approaches can potentially disrupt LSLs, and a utility should consider adding appropriate protective measures such as flushing and pitcher filters.
Mechanical test pits and vacuum excavation
Mechanical test pits and vacuum excavation – we found this to be the most common proven solution. It can range from a few hundred dollars to over $1000 per location. There is some concern that potholing may disturb piping during the inspection process.
Evaluate in-pipe solutions as needed
Evaluate in-pipe solutions as needed. In-pipe inspection methods can be used for service line assessments; however, they have a higher likelihood of disturbing pipes, and there is potential to slough or dislodge lead-containing pipe scales. If using these techniques, it is highly recommended that utilities provide residents with pitchers and filters to minimize the impacts of disturbed scale immediately following the inspection.
Utilities should also be prepared to promptly replace any lead or galvanized lines that are found – particularly if they’ve been disturbed – to protect public health and minimize exposure risks. Any technologies or devices that are installed into the drinking water system should be appropriately disinfected to prevent contamination. Additionally, if the pipe is disturbed, flushing should be conducted at the time of the work, and the utility should provide health information and flushing instructions to the resident. Some of these in-pipe inspection methods include:
Electrical Current
The use of a low-voltage conductivity probe to assess the material type of the pipe via electrical resistance is an emerging solution for in-pipe inspection. By measuring how strongly pipe materials resist electric current, these methods detect changes in resistivity as a probe travels through the service line. This allows for the identification of different materials – such as lead, which is non-magnetic and has distinct electrical properties.
CCTV (direct contact)
Some utilities have used CCTV technologies to provide camera footage from within the service line. In this practice, the meter can be removed and a CCTV line inserted into the service line for inspection. EPA’s guidance document provides a summary of this approach.
Use predictive modeling to enhance field verification
Consider predictive modeling to enhance the efficiency of field verifications. Predictive analysis methods are another popular approach to evaluating distribution system service line material. Predictive analysis methods leverage machine learning models to determine the likelihood that a given service line is lead or non-lead. Utilities should first confirm if their state accepts predictive modeling for this approach.
While field verification is still needed to ensure the accuracy of the models, they can provide benefits in prioritization of field activities and excavations. Several companies and engineering consulting firms can assist a utility in performing a predictive modeling of their distribution system. Predictive modeling can be used in various approaches:
Budget-level estimates of the number of LSLs
This approach can be used to make general assumptions about the number of unknowns without knowing exactly where they are located at the individual service line level.
Steering or prioritizing investigations or replacements
This approach can provide insights into areas with a higher probability of containing LSLs, allowing utilities to prioritize investigations and improve the likelihood of successful identification.
Predicting non-lead vs. lead for individual service lines
This approach requires a higher effort to field verify data and includes excavations to assess material types (e.g., 20% of unknown lines). While predictive modeling cannot predict all service line materials, it has been shown to significantly reduce the number of field investigations (e.g., up to 75%), which can save time and money. Predictive models must be continually updated as new inventory information is collected.
Toolbox
Predictive modeling for inventories
In-pipe methods
Emerging non-excavation solutions
In-pipe solutions
Predictive Modeling Solutions
Other tools
Key Action 4
Elevate Transparency through public-facing data
Making public inventory data accessible allows residents to assess their risk of lead exposure and track the utility’s progress in real time. This transparency not only empowers them to take proactive steps to protect their health but also strengthens trust in your replacement program—fostering greater community support and engagement.
Make data visible and accessible
Make data visible and accessible to the public. Utilities can create online maps by leveraging GIS platforms. Making this information accessible to the public allows residents to know where lead lines are in their community and empowers them to take appropriate actions to reduce their risk of exposure (see: Principle 4, Key Action 2). For utilities serving more than 50,000 people, inventory information must be publicly accessible online per EPA requirements; however, this is a best practice for any sized utility seeking to improve public trust. When making data visible to the public, utilities should:
- Include functionality in a public-facing map for residents to ask questions or self-report information about their service line materials.
- Clearly distinguish between public side and private side service line materials.
- Consider including a disclaimer that information may not be complete or up to date, and customers’ self-reporting can assist in the information collection process.
