Natural
events that will come to mind for most readers, and that many may have been
affected by, are floods – whether of the rapid overnight or slow-developing
over weeks type. Floods are normal things; they happen every year and in almost
every river valley. Sometimes they are minor events; other times they are
devastating – to people and communities. But they have been part of natural
phenomena forever.
Historically
most farming communities have benefited by river flooding that brought moisture
and deposited rich new sediment across fields.
Seared
into human memory, though, are the major, disastrous varieties, when
infrastructure and human lives were lost on a grand scale. For family
historians, again, such events may have ended up forcing people to migrate or
left chaos among the lives of survivors.
In
any year, as far back as records exist, one may find descriptions of floods
that disrupted communities and took lives.
Naturally
occurring floods are almost always a result of major storms. Exceptions are
those that arrive as tsunamis (see blog post of 20 June 2017). Along
shorelines floods may arise from sea surges, those also produced by storms in
the open ocean. Every continent has had its share of large-scale flooding.
Those with very extensive river systems or large collection areas may suffer
through floods extending over vast areas.
In
Europe the greatest disasters from flooding resulting from storm surges, coming
ashore mostly from the North Sea. The 1287 St. Lucia flood is reported to have
killed 50,000 to 80,000 people in the Netherlands and northern Germany. What
had been a large fresh water lake surrounded by farming communities and fronted
by barrier islands and peat swamps was turned into an extension of the North
Sea – the Zuiderzee. There were undoubtedly many similar floods in the region
as sea level rose following the last major ice age. There would be many more
such storms in succeeding centuries, particularly during the Little Ice Age (AD
1315-1850), until residents learned to mostly control them with dams, dykes and
surge barriers.
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A
major flood hit north-central England in November 1771. A storm broke over the
highlands of the Pennines with heavy rain for several days combined with
melting of snow in the highest reaches. All rivers flowing out of the region,
to the north, south, east and west overflowed their banks, from the source
areas to the tidal inlets, over 60 miles in the cases of the Tyne, Tees and
Wear Rivers.
In
many areas the water arrived in flash-floods with water levels rising over the
eaves of houses within minutes. Buildings of all types, ships tied up along the
wharves, goods left lying on quays, farm animals and implements and, of course,
people were swept away in the raging currents. Bridges, including the 500-year
old Tyne Bridge at Newcastle, were unable to withstand the onslaught of water
and were destroyed. In some areas, water levels in the lower reaches were over
12 feet above normal, high spring tides.
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Gaps through Pennine Mountains; Topographic Map
of the UK;
Mercator projection
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| Etching of Tyne Bridge at Newcastle after the 1771 flood; source – Newcastle Libraries |
In
North America, the Mississippi River and all of its major tributaries have
consistently inundated lands adjacent to their water courses. They are not called
floodplains for no reason!
The
drainage area for the Mississippi encompasses 1,245,000 square miles.
From its source in Minnesota, it takes on the flow from 10 major tributaries,
eventually dumping millions of tons of sediment into its delta area in the Gulf
of Mexico. During frequent floods it also delivers substantial volumes of new
soil to surrounding farmland in all the river valleys.
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Mississippi River tributaries, from USGS data
There
have been dozens of major flood episodes in the Mississippi basin, from upriver
storms, hurricanes arriving from the Gulf of Mexico or exceptional snow melt
from the Rocky Mountains and runoff in the tributaries coming from there. The
lower Mississippi always seemed to get the brunt of the excess water. The
earliest report of a flood is from 1543 when Spanish explorer Hernando DeSoto
arrived at the confluence of the Mississippi and Arkansas Rivers.
The
most disastrous
flood
in recorded history in the United States happened in 1927 as exceptional
amounts of rain fell along many of the major tributaries of the central part of
the basin. Over 27,000 acres were covered with water, with depths up to 30
feet, primarily in the states of Arkansas, Mississippi and Louisiana. More than
700,000 people were left homeless; 500 people died. Many of the displaced,
particularly those in the labouring class, gave up on the region and migrated to
northern and Midwestern cities. Following this event, the US Congress passed
the Flood Control Act of 1928, charging the US Army Corps of Engineers with the
task of establishing controls on the flow and flooding of the river system.
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1927 Mississippi River flooded areas - Records of the
Coast and Geodetic Survey, RG; source – Public Domain
In
China, major rivers have also experienced widespread flooding over the
centuries. The best documented are, of course, the most recent. In 1931, a
combination of melting of large snow accumulations in the western mountain
ranges, exceptional and heavy rain in the central regions and cyclone activity
from the eastern ocean saw substantial more volumes of water in the system than
normal. In addition, “[e]xcessive
deforestation, wetland reclamation, and the over-extension of river dyke
networks transformed regular flood pulses, which were an integral feature of
the fluvial ecosystem, into destructive inundations, which wrought chaos upon
human communities.” (DisasterHistory.org)
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Great flood at Gaoyou, Jingsu province; source - The Great Floods of 1931 at Gaoyou website
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Rebuilding of dykes following the disastrous
flooding in 1931; Sampans transport the soil to Gaoyou Dikes on the Grand Canal,
Jiangsu Province. Source - The Great Floods
of 1931 at Gaoyou
website
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The
cumulative causes, both natural and manmade, resulted in a devastating event
that affected 52 million people with two million deaths. Following the event
many programs were initiated to build new and better dyke systems and institute
flood control measures. These were built largely from manual labour of
thousands of workers.
Such
large-scale floods are not unique to modern times. No doubt all river systems
have seen excessive precipitation that resulted in widespread inundation. Where
no people were around
to
witness the events, they would not be considered as disasters. Today most
regions are highly populated meaning that even minor flooding can do
significant damage and affect many communities.
Family
historians may well find some of their ancestors were affected by floods. Such
evidence can be found in newspapers of the day, written up in parish or estate
accounts or detailed in many books and other publications.
