The records exist. The missing measurements do not.
Examining the 2014–2015 direct potable reuse project, the historical NDMA record, and what that history means for Wichita Falls' current indirect potable reuse system.
That means the NDMA concentrations we would most want to see today,
measurements from the drinking water during the 2014–2015 DPR
operation, were not collected as part of that monitoring.
Those measurements cannot easily be recreated now.
The existing records can still show what was known, what was
decided, what was tested and what was not.
What is NDMA?
N-nitrosodimethylamine, or NDMA, is a nitrosamine chemical that can occur in water and can also form during certain water and wastewater treatment processes.
It is important in drinking-water and potable-reuse research because NDMA can form when precursor compounds interact with disinfectants such as chloramines. Reverse osmosis alone may not remove NDMA consistently because it is a small molecule.
NDMA is classified as a probable human carcinogen based largely on animal studies. Drinking-water measurements are typically reported in nanograms per liter, or parts per trillion.
There is currently no federal maximum contaminant level for NDMA in drinking water. EPA has developed Method 521 specifically for measuring nitrosamines, including NDMA, in drinking water.
Explore the NDMA research →NDMA at a glance
EPA UCMR 2 monitoring detected NDMA in Wichita Falls finished drinking water.
Wichita Falls operated its emergency direct potable reuse system.
Wichita Falls began permanent indirect potable reuse through Lake Arrowhead.
I am asking for current NDMA testing and public review of the historical record.
A public record that can be checked and expanded.
I have spent months collecting laboratory reports, engineering documents, emails, regulatory records, scientific studies and public records related to Wichita Falls water and potable reuse.
This site brings those materials together so readers can move from a summary or timeline entry directly to the records and research supporting it.
It also gives the community a place to contribute relevant records, information, corrections and firsthand knowledge that may help build a more complete historical record.
The purpose is accountability, transparency and current testing. The historical record can be examined now. Wichita Falls water can also be tested for NDMA now.
Browse the source document library →What the historical record documents show
These are some of the records that changed the direction of my research. Source documents are organized in the public record library so the underlying material can be reviewed directly.
NDMA in Drinking Water
EPA UCMR 2 monitoring detected NDMA in Wichita Falls finished drinking water years before the emergency DPR project began.
See the 2009 test results →NDMA in Treated Wastewater
Testing during potable reuse feasibility work detected NDMA in treated wastewater before DPR operations began.
What was tested, and what was not →NDMA Monitoring Was Removed
Regulatory records document discussion of NDMA and the later request and approval to remove unregulated contaminants, including NDMA, from the DPR monitoring protocol.
See the monitoring record →The DPR Treatment System
Engineering and regulatory records document how treated wastewater moved through advanced treatment, blending and drinking-water treatment during the emergency project.
Review the DPR records →UV Treatment
UV treatment was added months after DPR operations began. Records document the equipment and operating dose used at the drinking-water treatment plant.
How UV dose relates to NDMA →July 2015 Testing
Water from the DPR treatment process was later tested during UV advanced oxidation work. NDMA was identified as a significant micropollutant in that testing.
Read about the 2015 pilot →The record spans more than a decade.
Federal monitoring detects NDMA
Wichita Falls participates in EPA's second Unregulated Contaminant Monitoring Rule program. NDMA is detected in finished drinking water.
Potable reuse feasibility testing
Wichita Falls evaluates emergency potable reuse during severe drought. NDMA is detected in treated wastewater during feasibility work.
NDMA is discussed, then removed from monitoring
Records document discussion of NDMA before DPR and the subsequent request and regulatory approval to remove unregulated contaminants, including NDMA, from the monitoring protocol.
Emergency DPR begins
Treated wastewater becomes part of the Wichita Falls drinking-water supply during the drought.
UV is added and DPR later ends
UV treatment begins after DPR has already been operating for several months. The emergency DPR system shuts down in July 2015.
Permanent IPR begins
Treated wastewater is discharged into Lake Arrowhead before later withdrawal and drinking-water treatment.
The historical record is assembled
Laboratory results, engineering records, regulatory correspondence, public records and scientific literature are collected and compared.
What is documented and what was not measured
The historical record contains substantial information about NDMA, the treatment system and regulatory decisions. It also has a major limitation: routine NDMA measurements from live DPR operation are not part of that record.
Documented in the Record
- NDMA was detected in Wichita Falls finished drinking water before DPR.
- NDMA was detected in treated wastewater during potable reuse feasibility testing.
- NDMA was discussed before the DPR system began operating.
- Records document a request to remove unregulated contaminants, including NDMA, from the DPR monitoring protocol.
- TCEQ approved the requested monitoring exception.
- Wichita Falls operated DPR from July 2014 through July 2015.
- UV treatment was added after DPR had already been operating for several months.
- Later testing of water from the DPR treatment process identified NDMA as a treatment concern.
- Wichita Falls later began permanent indirect potable reuse.
What the Historical Record Cannot Tell Us
- Routine NDMA concentrations in Wichita Falls drinking water throughout the 2014–2015 live DPR operation.
- How NDMA concentrations may have varied across the distribution system during DPR.
- How concentrations may have changed over the course of the year-long DPR operation.
- Individual historical NDMA exposure for any particular Wichita Falls resident.
- Whether any individual illness was caused by exposure to Wichita Falls drinking water.
I began as Dominic's mom.
I did not begin this as a researcher, engineer or environmental scientist. I began as Dominic's mom, trying to understand what happened in the years before my son's brain cancer diagnosis.
Dominic was diagnosed with glioblastoma multiforme in January 2018, at age 11. Five months earlier, in August 2017, another Wichita Falls boy named Gunner was diagnosed with glioblastoma multiforme at age 10. As I began looking more closely at our histories, I discovered that our families had lived approximately 400 feet apart during part of the years before their diagnoses.
I wanted to know what the boys might have had in common during that time. I began looking at the neighborhood, the surrounding area and eventually the water.
That search took me back to the severe Wichita Falls drought and the emergency direct potable reuse system the City operated from July 2014 through July 2015.
So I started looking for the records.
One document led to another. Water-quality reports led to federal monitoring data. Engineering documents led to correspondence. References to NDMA led to scientific literature, treatment research and additional public-record requests.
The search eventually grew beyond Dominic and Gunner as I learned about other childhood cancer diagnoses in Wichita Falls and began talking with other parents.
The records do not establish that Wichita Falls water caused Dominic's cancer, Gunner's cancer or any other illness. The health information and the water records are presented separately so each can be examined on its own evidence.
What began as a mother's search became an effort to reconstruct the history accurately enough that scientists, engineers, toxicologists, public-health professionals, regulators and the community can examine the same record for themselves.
Read the full story behind this project →What research tells us about NDMA and potable reuse
Peer-reviewed research and technical guidance provide context for understanding how NDMA forms, how it behaves during treatment and how treatment and monitoring approaches address it.
NDMA and Reverse Osmosis
Research on potable reuse systems documents the behavior of NDMA during reverse osmosis and why removal can vary.
Review the research →NDMA and UV
Ultraviolet light can photolyze NDMA. UV dose and treatment configuration are central to evaluating how effectively that process addresses NDMA.
Review the research →NDMA and Potable Reuse
Research from potable reuse systems provides information about NDMA precursors, chloramination, advanced treatment and post-treatment formation.
Review the research →Test Wichita Falls water for NDMA now.
The historical NDMA measurements that were not collected during DPR cannot be recreated. Current water quality can be measured.
I am requesting current NDMA testing of the Wichita Falls public water system using EPA Method 521, including finished drinking water and representative distribution-system locations, with sampling that includes operation of the City's indirect potable reuse system.
I am also asking the City of Wichita Falls and TCEQ to publicly address the historical records, including what was known about NDMA before DPR, the monitoring decisions that were made and the information that was available during and after the project.