Kentucky and Virginia hit by severe flooding: July to August 2022
The deaths of four young children from the same family have focused world attention on the devastating floods that hit eastern Kentucky and south-west Virginia in the final days of July 2022. At least 33 people are known to have died during the flash flooding (Lexington Herald Leader, 2022), although it is hard to give a definitive figure as the area’s infrastructure has been greatly affected by floodwaters and mudslides, meaning the death toll may rise as more reports reach the authorities (CNN, 2022a).
Event Overview
The Kentucky floods are the latest in a series of severe weather events that have affected the US in recent weeks, following floods caused by sudden heavy downpours in Las Vegas and a flash flooding emergency in St Louis which left one man dead after he became trapped in his car by rapidly rising waters (ABC News, 2022a). Similar floods were also experienced in Arizona and, at the time of writing, further flooding is forecast in Missouri (Forbes, 2022). The rain followed drought conditions in many areas, where dry ground was unable to absorb heavy rain, exacerbating the situation (ABC News, 2022a).
Rain began falling on Kentucky from the morning of 26 July 2022, continuing to 28 July. Over 250mm was reported in some areas, with the Kentucky and North Fork Kentucky rivers overflowing into 29 July: the North Fork Kentucky River was reported as being above Major Flood Stage at Whitesburg, while the Kentucky River was above Moderate Flood Stage at Heidelberg and near Ravenna (Floodlist, 2022).
The gauge located at Jackson on the North Fork Kentucky River recorded a record crest of 43.47 feet (13.25m), at 2.30am on 29 July, while another gauge at Whitesburg recorded a 20.9 ft (6.4m) crest (CNN, 2022a; CNBC, 2022). The heavy flooding that resulted from this left over 24,000 people without power at the storm’s height, with mudslides damaging bridges, homes and vehicles (Forbes, 2022).
By 31 July, 28 people were known to have died as a result of the flooding, with over 300 people having to be rescued from surging waters by the emergency services and many survivors being given temporary shelter at state parks and campgrounds (Washington Post, 2022). The death toll had risen to 33 by 1 August, with 16 of the victims from Knott County, six from Breathitt County, seven from Perry County, two from Letcher County and two from Clay County. Four of the victims were children from one family, who were killed when their home was inundated by rapidly flowing waters (Lexington Herald Leader, 2022).
Flooding in central Appalachia can be terrifyingly sudden, with water rushing down barren, mine-stripped hillsides. Residents often have little warning and few escape routes, which is why floods in the region can be so deadly (New York Times, 2022). The widespread poverty which affects many of the worst-hit areas will only add to the challenges faced by communities (BBC, 2022). Added to this, there is often a low take-up of flood insurance, especially as some of the affected areas have never flooded before (CNN, 2022b).
As waters began to recede on 2 August, residents and rescuers faced soaring temperatures, as well as the prospect of more rain in the forecast (CNN, 2022b).
The rain also affected south-western Virginia, where the federal government declared a state of emergency on 28 July 2022 (ABC News, 2022b). Torrential rain affected at least six Virginian counties, causing power outages, mudslides and travel disruption in these regions (CNBC, 2022). This event follows close on the heels of a previous flooding in Virginia only weeks ago, which damaged more than 100 properties in Buchanan Country (USA Today, 2022).
Flood Analysis
Figure 1: (Left) Map of eastern Kentucky showing two river gauges along the North Fork Kentucky River (ESRI Data and Maps, 2020; graphic © JBA RML, 2022). (Right) Extreme value analysis (EVT) conducted by JBA Risk Management for Jackson and Whitesburg, Kentucky USA, showing the estimated return period (in years) associated with the daily highest recorded level (in feet). The blue line represents the observed peak data at these sites on 29 July 2022. Historical gauge height data was fitted with a Generalised Pareto Distribution curve. Data was extracted from the United States Geological Survey for both locations (USGS, 2022a; USGS, 2022b).
River peak return period analysis was conducted based on river gauge height data for two locations along the North Fork Kentucky River in Kentucky. On 29 July 2022, the river gauges along the North Fork Kentucky River at Jackson recorded a crest of 43.47 ft (13.25m) and 20.9 ft (6.37m) at Whitesburg. Based on these measurements, JBA’s EVT analysis suggests return periods of approximately 30 and 75 years at Jackson and Whitesburg respectively.
According to USGS, the peaks recorded at Jackson and Whitesburg were the highest observed in 95 and 47 years respectively. Marshall Shepherd, Director of the Atmospheric Sciences Program at the University of Georgia, has suggested that flooding events with a return period of 100 years could soon become a 1-in-30-year event (ABC News, 2022c), meaning that the likelihood of such an event occurring in any given year would more than triple.
Climate change
Kentucky Governor Andy Beshear, noting that emergency responders who had worked in the area for 20 years had never seen water levels this high (BBC, 2022), was not the only one to highlight the unusual ferocity of the July 2022 event. Based on findings from the US Geological Survey – such as 8-10 inches (203-254mm) of rainfall in a 24-hour period – Kentucky State geologist Bill Haneberg labelled the floods “extraordinary” (Guardian, 2022a). Other environmental scientists have pointed to the increasing moisture capacity of the atmosphere due to global warming as a reason why rainfall events are beginning to result in more drastic consequences (Guardian, 2022b).
It’s vital that organisations act now in response to flood risk. JBA offers flood mapping and probabilistic flood modelling worldwide, including for the US. Our data provides flood risk insights at any location globally. This can help re/insurers, financial organisations, and the International Development sector to better understand and manage flood risk.
To find out more about our flood data and how it can help you, get in touch with the team.
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REFERENCES
ABC News, 2022a. At least 37 dead in devastating Kentucky flooding. [online] Available at: https://abcnews.go.com/US/26-dead-devastating-kentucky-flooding-expected-governor/story?id=87705278 [Accessed 2 August 2022]
ABC News, 2022b. Governor declares state of emergency amid Virginia flooding. [online] Available at: https://abcnews.go.com/US/virginia-governor-declares-state-emergency-flooding-devastates-commonwealth/story?id=87597942 [Accessed 2 August 2022]
ABC News, 2022c. Scientists explain how the deadly flooding in Kentucky got so bad: ‘It was bound to be catastrophic.’ [online] Available at: https://abcnews.go.com/US/scientists-explain-deadly-flooding-kentucky-bad-bound-catastrophic/story?id=87832020 [Accessed 2 August 2022]
BBC, 2022. Kentucky: At least 25 dead in worst Appalachia floods for years. [online] Available at: https://www.bbc.co.uk/news/world-us-canada-62351166 [Accessed 2 August 2022]
CNBC, 2022. Appalachian floods kill at least 16 as rescue teams deploy. [online] Available at: https://www.cnbc.com/2022/07/29/appalachian-floods-kill-at-least-16-as-rescue-teams-deploy.html [Accessed 2 August 2022]
CNN, 2022a. Deadly flooding in eastern Kentucky. [online] Available at: https://edition.cnn.com/us/live-news/eastern-kentucky-flooding-07-29-22/index.html [Accessed 2 August 2022]
CNN, 2022b. Kentucky flooding death toll rises to 37 as governor says hundreds remain unaccounted for. [online] Available at: https://edition.cnn.com/2022/08/01/weather/kentucky-appalachia-flooding-monday/index.html [Accessed 2 August 2022]
ESRI Data and Maps, 2020. USA Rivers and Streams. [online] Available at: https://hub.arcgis.com/datasets/esri::usa-rivers-and-streams/about [Accessed 2 August 2022]
Forbes, 2022. At Least 16 Killed By Kentucky Flooding – Toll Expected To Rise. [online] Available at: https://www.forbes.com/sites/siladityaray/2022/07/29/at-least-15-killed-by-kentucky-flooding-toll-expected-to-rise/?sh=35f447ae6981 [Accessed 2 August 2022]
Guardian, 2022a. Catastrophic flash flooding kills 25 in Kentucky and at least a dozen missing. [online] Available at: https://www.theguardian.com/us-news/2022/jul/30/kentucky-flash-flooding-death-toll-missing [Accessed 2 August 2022]
Guardian, 2022b. Kentucky grapples with effect of climate crisis as floods leave trail of devastation. [online] Available at: https://www.theguardian.com/us-news/2022/jul/31/kentucky-flash-floods-climate-crisis [Accessed 2 August 2022]
Lexington Herald Leader, 2022. ‘Still finding bodies.’ Death toll climbs above 30. About 50 bridges damaged, official says. [online] Available at: https://www.kentucky.com/news/state/kentucky/article264019321.html [Accessed 2 August 2022]
New York Times, 2022. Death Toll Rises in Devastating Kentucky Flooding. [online] Available at: https://www.nytimes.com/2022/07/29/us/kentucky-flooding.html [Accessed 2 August 2022]
USA Today, 2022. Dozens of people unaccounted for, over 100 homes damaged after flooding in southwest Virginia, officials say. [online] Available at: https://www.usatoday.com/story/news/nation/2022/07/13/buchanan-county-flooding-virginia-storm-damage/10050754002/ [Accessed 2 August 2022]
USGS, 2022a. NORTH FORK KENTUCKY RIVER AT JACKSON, KY. [online] Available at: https://waterdata.usgs.gov/monitoring-location/03280000/#parameterCode=00065&period=P7D [Accessed 2 August 2022]
USGS, 2022b. NORTH FORK KENTUCKY RIVER AT WHITESBURG, KY. [online] Available at: https://waterdata.usgs.gov/monitoring-location/03277300/#parameterCode=00065&startDT=2007-10-01&endDT=2022-08-03 [Accessed 2 August 2022]
Washington Post, 2022. Death toll for Kentucky floods climbs to 28, with more storms coming. [online] Available at: https://www.washingtonpost.com/nation/2022/07/31/kentucky-flood-climate/ [Accessed 2 August 2022]
