Friday, 17 July 2015 09:58

Four Examples of Designs that Reduce the Site-Specific Health Risks of Climate Change. Example 3: Drought/Flood Cycle.

Flood vulnerability map of Austin, TX


Drought/Flood Cycle

Health Impact

The drought/flood cycle has already shifted in many parts of the U.S. due to climate change. Heavy precipitation events are becoming more common each year, concentrating annual rainfall into a smaller period of time each spring, and washing water downstream that historically would have replenished lakes, rivers, and aquifers. Less precipitation falls throughout the remainder of the year, leading to drought conditions. Drowning is the most direct health effect of flooding, resulting in 98 deaths per year in the U.S. It is of particular concern in areas prone to flash flooding and/or tropical storms. Other health impacts associated with drought and flooding include waterborne illness caused by compromised water quality and respiratory illness due to damp indoor environments (flooding) or exposure to wildfires or dust storms (drought). (Source: 3rd National Climate Assessment.)


Central Texas is known as “Flash Flood Alley,” due to the rapidity and severity of flooding that occurs there, particularly following major droughts. In 2008, I co-authored a vulnerability map of Austin, TX, that identifies the neighborhoods with them most acute combination of social vulnerability (e.g., population density, elderly, socially isolated, and minority populations) and environmental vulnerability (e.g., flood plains and low water crossings).

Design Strategy

In subsequent research, I found that evidence in the public health literature supported applying a number of credits in the U.S. Green Building Council’s Leadership in Energy and Environmental Design (LEED) rating system as protective measures in vulnerable neighborhoods. These green building strategies include:

    • promoting the use of alternative forms of transportation to provide multiple evacuation options during flooding events;

    • increasing native vegetation on-site to maximize stormwater retention and filtration; and,

    • making use of rainwater to irrigate, flush toilets, and even provide potable water during and immediately following flooding events.

Relevant LEED v4 Credit(s)

Site assessment
Sensitive land protection
Access to quality transit
Reduced parking footprint
Site development – protect or restore habitat
Open space
Rainwater management
Heat island reduction
Outdoor water use reduction
Indoor water use reduction

Benefits to Climate Change Mitigation

Site shading can reduce a building’s electricity use, one of the major causes of anthropogenic (i.e., human caused) greenhouse gas (GHG) emissions. Alternative forms of transportation reduce the other major source of GHG emissions associated with the built environment – single occupancy car travel.

Benefits to Climate Change Adaptation

Reduce exposure of vulnerable populations to flash flooding. Mitigate exposure through multiple evacuation routes and access to potable water if occupants choose to shelter in place during a flood.

Go Back to Extreme Heat Example.  Continue to Disease-Carrying Insects Example.
Go Back to Main Post


Copyright: © Biositu, LLC, and Building Public Health, 2015.

Leave a comment

Make sure you enter the (*) required information where indicated. HTML code is not allowed.

Signup For Our Newsletter!