Flooding from Hurricane Harvey causes a host of public health concerns
Yet despite the threats from polluted floodwaters, most diarrhea is caused by failed drinking water systems. The massive supplies of bottled water distributed after the flood can help, but getting drinking water systems up and running again is essential, albeit a formidable challenge. These systems are designed to provide multiple barriers to protect the water sources, treatment plants and distribution pipes from contamination.
Mold and mildew, meanwhile, can harbor disease agents that affect respiratory systems long after floodwaters have dried. Mosquito-borne illnesses such as malaria and dengue are endemic in flooded areas. Then, chemical and explosive hazards can affect people in ways ranging from cancer to exposure to fire and detonations.
Beyond infections
There is also trauma from flooding which can can take many forms, such as blunt force injuries due to flash floods or explosions. Objects such as propane bottles and fuel tanks should be anchored to prevent them from being released.
Traffic disruption and failure of structures, such as bridges and culverts, can cause injuries as well. Thirty years ago, a New York State Thruway bridge collapsed from flood damage, killing 10 people. The cause was damage from erosion to supporting bridge piers, which travelers could not detect or see.
If we are to learn more about flood-induced injuries and diseases, better data are needed. Epidemiological studies of flood impacts are limited, particularly in study of long-term mental health, mortality risks after flooding, risks of infectious and vector-borne diseases following floods, and the effectiveness of public health measures in reducing flood-related health burdens.
Moreover, the health-related costs of flooding are not considered adequately in decisions about remedies, and little is known about the effects of climate and land-use change on flood risk and health burdens in different settings.
The Houston disaster was caused by an unprecedented flood, but other rare and extreme ones occur. They are in the U.S. headlines for a few days, and then they disappear, especially when they happen in faraway places. The 2010 Pakistan flood affected 20 million people, but it disappeared from the news within days. In worst-case scenarios, floods can kill hundreds of thousands and maybe millions, as one did in China in 1931. In countries with limited resources, people are mostly left to fend for themselves.
What can be done to alleviate future suffering from such massive events? Flood science has some of the answers, but not a complete solution. The good news is that most flood threats occur from frequent events, which can be mitigated by a combination of steps that include adequate infrastructure and so-called nonstructural tools, which means they involve measures such as zoning, flood warning and insurance.
These, along with pollution control programs, can go a long way toward alleviating the worst impacts of flooding. The catch is they must work, and this requires the rule of law and good governance, which are unfortunately lacking in many parts of the world.
Neil S. Grigg is Professor of Civil and Environmental Engineering, Colorado State University. This article is published courtesy of The Conversation (under Creative Commons-Attribution / No derivative).
