Grantee Research Project Results
2023 Progress Report: Open source, networked sensors for lead monitoring
EPA Grant Number: SU840415Title: Open source, networked sensors for lead monitoring
Investigators: Pennock, William , Basuray, Sagnik , Warholak, Michael , Kutzing, Sandra , Ahmad, Afaq , Pennock, Andrew , Rios, Lara , Brzostek, Michael , Burns, Mark , Pong, Philip , Talebi, Maryam , Shah, Eishah
Institution: New Jersey Institute of Technology
EPA Project Officer: Harper, Jacquelyn
Phase: I
Project Period: July 1, 2022 through June 30, 2023 (Extended to June 30, 2024)
Project Period Covered by this Report: July 1, 2022 through June 30,2023
Project Amount: $24,982
RFA: 18th Annual P3 Awards: A National Student Design Competition Focusing on People, Prosperity and the Planet (2021) RFA Text | Recipients Lists
Research Category: P3 Awards , P3 Challenge Area - Safe and Sustainable Water Resources
Objective:
The city of Newark, NJ made headlines in 2016 and for several years after due to elevated lead levels in drinking water. In response, Newark replaced the lead service lines implicated in the lead release, completing their campaign in early 2022. Newark has set an example for the state and the country, with federal and state laws mandating the replacement of lead service lines in the next decade. Lead service lines were widely employed throughout the area surrounding Newark and in other parts of New Jersey, notably around Trenton and Camden, and much work remains to be done in the state of New Jersey.
However, even after the replacement of lead service lines, lead precipitates originating from the lead service lines can persist in premise plumbing, remaining a threat to human health, especially for children. Additionally, while the Safe Drinking Water Act (SDWA) banned use of high-lead pipe and solder in 1986, fittings were only included in 1996 in an amendment, and the allowable percentage of lead was 8% up until 2011 with the passage of the Reduction of Lead in Drinking Water Act (RLDWA). As a result, real-time monitoring of lead concentrations in the plumbing of these key urban centers in New Jersey will be important for the next several years, especially as the revised Lead and Copper Rule will set stricter sampling procedures and a lower trigger level that will require more municipalities to address their lead service lines and plumbing in 2024.
Monitoring lead concentrations in real time within vulnerable households and institutions is not routinely done. Lead levels are generally measured by taking first draw and flush samples at an end-point and testing the sample at a lab by inductively coupled mass spectrometry (ICP-MS). Colorimetric sensors have been developed for immediate readings, but these, too, require someone to physically take a sample. Potentiometric sensors have shown promise, but require periodic calibration and have a lifetime measured in weeks. In 2017, researchers in the Burns Lab at the University of Michigan put forth a simple platinum electrode design that works by reducing and precipitating heavy metals at the gap between the electrodes and measuring the resulting change in impedance.
The aforementioned lead sensor was tested at two gap widths and one voltage for the 2017 study. Further optimization was reported in a 2022 article in which the investigators tested 5 additional gap widths as well as agitating the solution, improving the sensor response time from about three weeks in the 2017 paper to one day in the 2022 paper for a 15 ppb Pb simulated tap water solution. The sensors have the important advantages of being on-line, continuous, self-cleaning, and relatively quick and inexpensive.
One disadvantage, however, is that the sensors provide semi-quantitative data, a trigger based on a circuit created by PbO2 forming a bridge between the anode and neutral electrode. Given variability in physical and chemical conditions within plumbing and resulting variability in lead levels, users of these sensors will be interested to know whether a triggering of a sensor represents a spike where a trigger or action level was exceeded or simply an accumulation over time from low levels of lead. One objective of the Phase I project is to correlate patterns in the sensor data with measurements of lead concentration and other physical and chemical parameters to better interpret readings from the sensors.
A second objective was to develop low-cost modules for the sensors that could interface physically with premise plumbing and electronically with the sensor and network with computers to provide continuous measurement of lead levels in premise plumbing. The original project team comprised two undergraduate students, providing first-time research experience for them. An additional graduate student and undergraduate student have since been added to the project. The original undergraduate students were alumni of a local high school (Bloomfield High School), and a course taught by their former teacher had high school students design the sensor module housing, which is an ongoing effort.
The project was developed with the goal of reporting summary data to Newark Sewer & Water and CDM Smith to inform their decision-making regarding lead service lines in the City of Newark. With more frequent data on lead levels within premise plumbing, water authorities can make more real-time decisions on when to flush water lines, adjust corrosion control, or shut down for system maintenance. For this, the third objective was to develop infrastructure for collecting, processing, and reporting data from the sensor modules. This involved developing a database and a website.
The fourth objective was to test the sensor modules in a real-world setting. This was envisioned as installing sensor modules on taps in the City of Newark. The resulting data would be used to improve the deliverables from Objectives 1–3 and provide an opportunity to study the dynamics of lead release across a water distribution network.
Progress Summary:
The Phase I grant was awarded in June 2022, a few months after the City of Newark closed out their lead service line replacement program. With the closeout of the lead service line replacement campaign, the Newark Department of Water and Sewer Utilities, which completed an LOI for the Phase I grant, was no longer interested in further investment in understanding and characterizing lead contamination of its drinking water. After the original partnership with Newark Department of Water and Sewer Utilities was determined to be infeasible, we explored partnerships with multiple utilities with the help of Sandy Kutzing, including Passaic Valley Water Commission (PVWC), who are currently replacing lead service lines on their system. The PVWC collaboration seemed the most promising, but an unanticipated short-staffing condition rendered them incapable of the additional work required for the collaboration.
I have since begun fruitful discussions with Mott MacDonald, an engineering consulting firm with strong local ties to NJIT and ongoing business relationships with multiple utilities. As utilities generally have little availability for work outside of their mandate, it has proven helpful to partner with businesses that contract with utilities, since their ongoing relationships help ensure continuity in communication and an open door for new ideas and projects. Additionally, consulting firms have more intrinsic motivation to pursue innovative water infrastructure projects, which are more in line with their mission as compared with that of utilities. Mott MacDonald has facilitated our current utility partnership, which includes access to a pipe loop. Through Newark Water and Sewer, we also have access to a lead-containing pipe loop available for experiments. These pipe loops provide the real-world environment of Objective 4 and data for the analysis required for Objective 1.
To date, work has been done on multiple aspects of the sensor module development. The undergraduate students originally involved in this study developed the basis for firmware for the sensor modules based on Arduino with an ESP 32 microcontroller. They also developed architecture for a website to store data in a database and display it. A run of 10 sensors were fabricated at the University of Michigan and are being used to develop the sensor modules. The project has been taken up by Eishah Shah, an undergraduate majoring in electrical and computer engineering, starting in Fall 2023. A class at Bloomfield High School also worked on a preliminary design for the layout of the sensor modules, and we hope to continue this collaboration.
The work on assessing the sensitivity of sensors was delayed for two reasons. First, the graduate student expected to work on this project, Maryam Talebi, who was anticipated to join the lab in Fall 2022 was delayed until Spring 2023 due to visa challenges. This and the unexpected search for a new utility partnership were the main reasons for requesting a no-cost-extension, which was granted as the Phase I project continues.
Future Activities:
Because of increased regulatory pressure to remove lead service lines and to lower the trigger and action levels for lead concentration in homes, this is a uniquely important time to have more granular data on lead concentration levels in drinking water. The sensor developed and improved by the Burns Lab has advantages that may make it the preferred way to accomplish this. Finding utilities willing to take on the extra work of collaborating on sensing work and open to additional outside data collection on their lead concentrations is a challenge. The State of New Jersey, where some of the country’s oldest drinking water infrastructure was built, and which has a large inventory of lead-bearing pipes and fixtures, is an excellent setting to pilot the use of these sensors in realistic conditions.
Journal Articles:
No journal articles submitted with this report: View all 1 publications for this projectSupplemental Keywords:
Environmental justice; urban water planning; drinking water; lead detection; platinum electrode sensor; premise plumbing; lead service line; machine learningRelevant Websites:
AguaClara-NJIT-Sensor-Code Exit
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.