Office of Emergency Coordination (OEC)

OEC Update: April 2019 Floods – Part 1; Springtime Weather; OEC Personnel Changes

Past issues of the OEC Update are archived on the O drive at: O:\CERT\OEC Publications\OEC Update.

Floods – Part 1

Floods are the most common and wide-spread of all weather-related natural disasters and, in general, they kill more people each year than tornadoes, hurricanes, or lightning.

– Flooding caused by the gradual rise in water levels associated with constant rains over time (riverine flooding) is generally predictable and warning times are sufficient to allow safe evacuation of affected communities. Few fatalities are expected with these events, although some increases in injuries and illnesses may be expected.

– Flash flooding, by contrast, can be highly dangerous because it combines the destructive power of a flood with rapidly flowing water, and it can happen with little or no warning. The leading cause of death is drowning, and the majority of all drownings in flash floods are related to motor vehicles (this is illustrated in the table below, which describes the circum-stances of flood-related deaths during a period of flooding in Georgia).

– Flash flooding and riverine flooding can at times occur almost simultaneously.

In Missouri, flooding occurs frequently, and is the deadliest severe weather hazard in the state. As is the case elsewhere, the vast majority of fatalities occur during flash flooding, and people in vehicles are at particular risk in this type of incident. According to the State Emergency Management Agency (SEMA), from 2015 through 2018, 34 of Missouri’s 39 flooding deaths – 87 percent – were people who had been in vehicles.

One way to better understand a flooding incident is by examining its individual phases:

– Quiescent phase

For a variety of reasons, people choose to live in areas prone to flooding. Many years or decades may pass before a significant flood occurs, and those living in these areas become complacent and tend to minimize the risk. Consequently, they are unprepared should a significant flood occur. In addition, many people do not give sufficient consideration to the dangers of flood waters, particularly the very real risk associated with trying to drive through a flooded area of roadway.

– Prodrome phase

May consist of a gradual rise of rivers overflowing their banks over the course of hours to days, or it may be rapid in the event of a flash flood. During this time, warnings will be issued by the National Weather Service and local emergency officials, but many people may not receive these warnings, especially with flash floods.

– Event phase

While flooding is taking place, those affected can be exposed to a variety of hazards, and as a result be at risk for injuries and illnesses.

Flood-Related Deaths by Circumstance of Death – Georgia, July 4–14, 1994 (MMWR 1994; 43:528.)

NSSL/NOAA

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In some instances, especially with a flash flood, traffic jams or obstructed roads may make it difficult or impossible for people to get out of flooded areas. Also, despite warnings, some people may choose to not leave until the last possible moment, and then feel they have no choice except to drive through roads covered with water.

In major flooding incidents, large numbers of residents may flee their homes. For example, the 1993 flooding of the Mississippi and Missouri Rivers displaced hundreds of thousands of persons over a multi-state region. In Missouri alone, approximately 60,000 individuals were reportedly displaced.

In situations where significant numbers of persons are displaced from their homes, the use of community shelters will be required. Some displaced persons, as well as some persons who cannot leave their homes, will have medical needs, including access to medications or to services such as dialysis. Populations that could be especially impacted by significant flooding include patients in long-term care facilities and individuals requiring home health services.

– Recovery phase

This phase is heralded by the onset of the floodwaters receding. Recovery from a significant flood will take weeks to years, and after major flooding, the costs may be in the millions of dollars. Persons involved in clean-up/recovery efforts can continue to be exposed to a variety of hazards, and thus be at risk for injuries and illnesses.

The next issue of the OEC Update will discuss specific flood-related hazards, the potential impact of floods on healthcare and public health, and the response of public health agencies to this type of incident.

Information and guidance on floods is available on DHSS’ Natural Disasters and Weather Emergencies webpage at https://health.mo.gov/emergencies/ert/naturaldisasters.php#floods. Information on current and projected future river levels is available at https://water.weather.gov/ahps/region_forecast.php?state=mo.

References:

1. SEMA. Flooding. https://sema.dps.mo.gov/plan_and_prepare/flooding.php

2. CDC. Flood-Related Mortality – Georgia, July 4–14, 1994. MMWR 1994; 43(29):526-30. https://www.cdc.gov/mmwr/preview/mmwrhtml/00032058.htm

3. CDC. Morbidity Surveillance Following the Midwest Flood — Missouri, 1993. MMWR 1993; 42(41):797-8. https://www.cdc.gov/mmwr/preview/mmwrhtml/00022056.htm

4. Floyd, KD. Floods, in Hogan DE, Burstein JL (Eds.). Disaster Medicine (Lippincott Williams & Wilkins, 2002): 187-93.

5. NOAA/NSSL. Severe Weather 101 – Floods. https://www.nssl.noaa.gov/education/svrwx101/floods/

Springtime Weather

In addition to flooding, springtime brings to Missouri increased chances for severe thunderstorms and tornadoes. Information and guidance on these storms is available on the Natural Disasters and Weather Emergencies webpage at https://health.mo.gov/emergencies/ert/naturaldisasters.php. In particular, see the sections entitled: 1) Weather Warnings, Forecasts, and Related Information, 2) Thunderstorms, and 3) Tornadoes. The internal links at the top of the page can be used to go directly to these sections.

Appendix A provides more information on preparing for, and protecting yourself and your family from, severe weather. Of particular importance is having a severe weather plan for your family, and having multiple ways to receive severe weather warnings (e.g., mobile warning apps, TV/radio, and NOAA Weather Radio).

Office of Emergency Coordination (OEC) Personnel Changes

On May 1, Melissa Friel became the new Chief of OEC, a role which includes management of the department’s Emergency Response Center (ERC).

Jody Starr has a new role within DHSS as the Public Health Emergency Preparedness (PHEP) Program Coordinator.

Appendix B contains public health-related information and guidance from the Division of Community and Public Health that has appeared recently in SEMA’s Daily Briefs.

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Appendix A Severe Weather Safety information

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Appendix B Recent Slides Developed by DHSS’ Division of Community and

Public Health Staff for SEMA’s Situation Reports (SITREPs)

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