Catalyzing Solutions: So what exactly happened in Flint?

Many phenomena that we observe in our everyday lives can be explained with scientific concepts. Similarly, many challenges that we observe in areas such as the environment or medicine are addressed using these ideas. The goal of this weekly column is to inform readers on some of these scientific concepts and illustrate the research that is currently being done at Colorado College to address these problems.

By JOSE MONGE CASTRO

Flint’s water crisis is a harsh reminder of the vulnerabilities within the current structures on which modern life relies, aside from the problematic power structures that lead to them. The crisis also highlights the complexity around providing communities with essential services and how highly specialized knowledge is necessary to ensure appropriate delivery.

The money-saving switch from Detroit’s water supply to locally treated river water toppled the dominoes. In general, water supply systems go through rigorous and years-long evaluations before determining ideal protocols of treatment. In Flint, the switch took mere months.

Additionally, rivers are among the most complicated aquatic chemical systems; mobile compounds, micro-organisms, and pollutants are usually present at high concentrations. For example, the high concentration of corrosive chlorine, largely from road salt, is a complication of North American bodies of water.  This element, along with oxidants such as dissolved oxygen, reacts with metals such as iron and lead in the pipes, yielding the toxic soluble compounds, which are also responsible for color and odor.

To combat this, water engineers add coagulants: compounds containing orthophosphate that form solid insoluble complexes to capture and deposit the otherwise mobile metal ions on the walls of the pipes. This common-sense measurement was neglected during Flint’s switch, saving the city about $140 per day.

Without these compounds, iron and lead immediately started leaching into the water supply.  To further complicate the issue, leached iron from some of the pipes reacted with the chlorine ions, impeding chlorine from acting as a disinfectant. With the consequential spike in bacteria, the city was forced to increase chlorine concentration, which led to even more corrosive water. Furthermore, though it controlled bacteria, the addition of more chlorine led to higher concentrations of trihalomethanes, known carcinogens.

In short, stopping the addition of orthophosphate led to the corrosion of pipes, which, given the complex nature of the system, led to a series of other problems. Permanent solutions are costly and not in sight. It is also worth noting that although Flint made the headlines, similar problems are present and unnoticed in many places around the U.S. and the world. Home kits to detect common water pollutants are not too expensive but are limited, and it is ultimately the cities who receive taxes and public trust who should ensure that water, a universal right, is safe to use.

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