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- Note From Sologic:

The investigations into the Flint Water Crisis are ongoing. Our root cause analysis discovered many areas that simply dead-end without answers. Those answers may come in time.  However, there is enough information available from a variety of credible sources for us to understand at a fairly detailed level what happened in Flint.

It should also be noted that this problem is highly politicized. The politicization of any problem adds to its complexity due to the systemic introduction of bias. The purpose of a root cause analysis is to find evidence-based facts, show how they interact with one another to result in the adverse event, and then to use that understanding to identify effective solutions.  Bias from investigators and reporters makes finding evidence-based facts difficult, but not impossible.

Finally, we need to disclose that this root cause analysis is based on publically available information from a variety of sources – not independent investigation conducted by Sologic.  Sologic has no official capacity to investigate what happened in Flint, and we do not want to imply that this is the case. The primary purpose of this root cause analysis is for it to be used as an example for our students and others.

This RCA breaks the crisis in Flint down into two main branches: The public health hazard, as represented by the contaminated water, AND the response by all levels of government – from local to state to federal. This is a strategy we often employ to examine both the “error path” (in this case, the contaminated water) and the “response path” which can mitigate or exacerbate the overall impact of the problem.

A large problem like this requires proper set-up in order for the cause and effect analysis to unfold in an orderly fashion. The Focal Point (problem being analyzed) of “Negative Public Impact – Flint Water Crisis” is purposefully broad, yet limited to the the water contamination issue. The causes of the impact of the crisis are two-fold: 1) The water was contaminated; and 2) The response by all levels of government to the crisis was delayed and ineffective. The combination of these two main causal themes explain at a high level the degree of severity of the problem. The next level of causes is also important. We start broadly with “water contaminated” but then need to break it down into the three individual contaminants: Lead, legionella bacteria, and trihalomethane. Each of these has separate causes, and therefore require divergent analysis. Likewise, the government response gaps need to be examined at each level of government. Therefore, we break this section down by the government taxonomy of local, state, and federal levels, and then break each of those down where appropriate to examine the specific causes at each level. 

Analyzing a big problem like this requires a bit of restraint along with substantial organization and focus as the details can become quickly overwhelming. But once the setup is complete, the rest of the cause and effect analysis is relatively easy to build – as long as the information is available. However, as mentioned above, information about this problem is still being discovered so this report should certainly be considered as interim. Still, it provides a timely example of a root cause analysis on a major event.

Cause and Effect Summary
On April 25, 2014, the City of Flint discontinued using water supplied by the Detroit Water and Sewerage Department and began sourcing the city’s water from the Flint River. Within a few months, residents began reporting that their tap water was murky, discolored, and foul-tasting.  Residents also began reporting health issues, such as loss of hair and eyelashes, stomach issues, and rashes, among other ailments. These ailments coincided with the switch in water supply.  Yet, response by Government at all levels was delayed. Residents were assured that the water was fine and that they had nothing to worry about. But this was incorrect. The tap water in many places contained dangerously high levels of lead – in some cases high enough that the tap water met the Federal standard for toxic waste. The tap water also contained elevated levels of e-coli bacteria, Legionella bacteria, and trihalomethane (a byproduct of chlorine interacting with organics). It is important to note that there is a natural variance in contamination from home to home – Flint has a large number of homes, each of which may have a different level of risk for lead contamination. However, testing methodologies should illuminate the areas at greatest risk, allowing authorities to respond appropriately.

Causes of Water Contamination:
Flint’s drinking water contained unacceptably high levels of lead, Legionella bacteria, and trihalomethane (THM). It is unclear where the legionella bacteria originated or whether it was causally related to this overall event at this point. They detected high levels, but they do not yet (and may never) know the source. However, it is relevant to discuss in the context of the broader water quality issue because, regardless of source, the presence of legionella bacteria at levels detected should have triggered a government response, and it did not.

The causes of the THM levels are known, however. THM levels are regulated by the EPA as it is a suspected health hazard. High levels of e-coli bacteria were discovered in the Flint water supply, prompting the decision to treat it with chlorine. Chlorine kills e-coli, but at high levels it interacts with other organics in the water, one result of which is THM. As with the legionella bacteria, this is relevant because it coincided with the switch in water source and it did not trigger the appropriate government response in a timely manner.

The lead, however, has been the primary focus of attention. Lead, at any level, is dangerous to humans – particularly children. The overall standard for lead levels in water is the EPAs Lead and Copper Rule (LCR). It sets the maximum acceptable lead level at 15 parts per billion. The lead concentration in Flint’s water varied from tap to tap, but was dramatically higher (in one case as high as 13,200 ppb) in broad sections of the city. These elevated levels coincided with the switch in water supply to the Flint River and was caused by the process of corrosion.

At a high level, the chemistry of corrosion is pretty simple: Atoms from one material transfer to another. In this case, the lead (from existing pipes, fittings, and solder) was subjected to water that was acidic. The acidic water, over time, dissolves some of the lead.

Lead pipes have been used for a very long time. Lead was abundant, cheap, and easy to work with. Also, the dangers were not clearly understood until more modern times. However, through the process of chemical corrosion control, lead pipes can be rendered safe. Water treatment plants inject phosphate corrosion inhibitor into the water which, over time, deposits a protective layer over the inside of pipes. This encapsulates the lead, preventing it from dissolving. The ph level of the water is also treated to keep it within a neutral range. So the process of chemical corrosion inhibition effectively manages the risks of legacy lead piping.

The water from the Flint River has a relatively low ph – it is acidic. The causes of this are unclear at this point, but the low ph indicates the corrosive level of the water from the Flint River. Over a few months, the acidic water ate away the protective layer inside the pipes, exposing the lead. It then was able to react with the lead, thereby increasing lead levels in the water supply.

Corrosion Control:
After making the switch to the Flint River, the Flint Department of Water Quality decided to not actively control corrosion. Before, when the water came from Detroit, it was already treated.  However, once the switch was made, a “wait and see” attitude was adopted. The burden of proof shifted from “prove it’s safe” to “prove it isn’t safe.”

To sum it up, acidic water plus time plus lead minus corrosion control equals lead-poisoned water.

Switch in Water Supply:
The City of Flint is in serious financial distress, and has been for some time. The State of Michigan has appointed “Emergency Managers” who supersede the authority of the local elected government. It is their job to get things back on track financially for the city, and they have broad powers to do so. A new water supply is in the process of being established (the Karegnondi Water Authority). Switching to this source was estimated to save the city $200 million dollars over a 25-year period. However, this system has not yet been completed. In the interim, the decision was made to temporarily switch to the Flint River. The Flint River had been the designated backup water supply, and was therefore considered an acceptable interim solution. 

It is safe to say that no one involved predicted the magnitude of the crisis this decision was putting into motion. However, this is part of the problem. The City of Flint had no experience with a major switch in water supply. They were, in the capacity that existed at the time of the switch, incapable of anticipating and mitigating risks. Their experience level, along with the desire for a quick financial turnaround, provided a fertile environment for an event of this magnitude to take place.

The City of Flint was unprepared at virtually every level for a project like this. The experience level of the managers involved was limited. The water quality sampling methodologies were inadequate in that they did not identify the correct households to test, and they did not follow prescribed sampling methods. The Flint Water Treatment Plant was out of date due to lack of investment. And there were gaps in the process of checks and balances due to the power held by the emergency managers.

The Genessee County Health Department could have raised awareness of high concentrations of lead in blood samples from children, as well as the presence of legionella bacteria. But they did not, primarily due to the fact that they did not allocate sufficient resources to the task.

The federal EPA delayed exercising its authority because it relies primarily on state-level environmental agencies to enforce the LCR. And it allows differing compliance strategies regarding the LCR – there is no consistent enforcement approach.

Michigan State Government – Breakdowns at Multiple Levels:
The Michigan Department of Environmental Quality (MDEQ) is responsible for enforcing the LCR. However, the MDEQ misapplied the rule, its staff was dismissive and unresponsive to complaints and reports, and they delayed accepting assistance from EPA lead experts. This resulted in under-reporting lead levels over a period of months which delayed response, thereby prolonging and exacerbating the impact of the contaminated water.

The Michigan Department of Health and Human Services (MDHHS) did not collect enough data on childhood blood lead levels as required by Medicaid. The data they did collect was not analyzed in a timely fashion. And once analysis was complete, they did not correctly interpret the blood lead level data. The default assumption was that the high lead levels were due to some other reason than the switch in water supply.

The Governor’s office relied on inaccurate information from MDEQ and MDHHS, and discounted other sources of accurate information.

Finally, the response to complaints from residents at all levels of government was delayed.  Customers made numerous complaints that were ignored. And samples of brown, murky, discolored tap water were dismissed as “within acceptable limits.”

More information will undoubtedly come out in the months and years to come. For now, we hope this is helpful as a guide to the use of Sologic root cause analysis as applied to a large problem.

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Root Cause Analysis training by Sologic provides the tools, skills, and knowledge necessary to solve complex problems in any sector, within any discipline, and of any scale.  Learn More


Sologic’s Causelink has the right root cause analysis software product for you and your organization. Single users may choose to install the software locally or utilize the cloud.  Our flagship Enterprise-scale software is delivered On Premise or as SaaS in the cloud.  Learn More