From the University of Southampton , word that mostly increased flooding is a reporting bias due to proximity, much like we have a reporting bias in tornado counts because there are more people to witness them than 50-100 years ago and greater urbanization.
Increase in reported flooding a result of higher exposure
A rise in the number of reported floods in the UK over the past 129 years can mainly be explained by increased exposure, resulting from urban expansion and population growth, according to new research by the University of Southampton.
In one of the most comprehensive studies of its kind, scientists have discovered that although the number of reported floods has gone up during the 20th and 21st Century, this trend disappears when the figures are adjusted to reflect population growth and increased building numbers over the same period.
Published in the journal Hydrological Sciences, the study looks at data sets from 1884 to 2013 and found an upward trend in reported flooding, with flood events appearing more frequently towards the end of the 20th century, peaking in 2012 when annual rainfall was the second highest in over 100 years.
The rise in UK flood reports over the 20th Century coincides with population growth from 38.2 million to 59.1 million and a tripling in the number of houses, from 7.7 million to 24.8 million.
“As a result there were more properties exposed to flooding and more people to report flooding,” says lead author Andrew Stevens. “A higher exposure to flooding will result in more reported flood events and larger potential damages.”
The study found significant variation between decades in both the raw and adjusted data, with the years between 1908 -1934, 1977 – 1988 and 1998 – 2013 featuring a relatively high numbers of reported floods.
The effect of increasing and improving flood defences is unclear. While upgrades to artificial defences, like the Thames Barrier, have reduced the effect of extreme sea level events, natural flood defences may have declined over the study period.
“Attributing periods of reduced flood damage simply to the effects of improved management is difficult and must be done with care,” says co-author Derek Clarke.
Professor Robert Nicholls adds “These observations should not stop concern about future flood impacts, especially in coastal areas where faster sea-level rises are expected and areas potentially exposed to higher rainfall intensities. Future flood risk may be very sensitive to changes in funding or management approaches and this has important implications for decision makers.”
The paper:
http://dx.doi.org/10.1080/02626667.2014.950581
Trends in reported flooding in the UK: 1884–2013
Andrew J. Stevens, Derek Clarke & Robert J. Nicholls
Abstract
A long term dataset of reported flooding based on reports from the UK Meteorological Office and the UK Centre for Ecology and Hydrology is described. This is possibly a unique dataset as the authors are unaware of any other 100+ year records of flood events and their consequences on a national scale. Flood events are classified by severity based upon qualitative descriptions. There is an increase in the number of reported flood events over time associated with an increased exposure to flooding as floodplain areas were developed. The data was de-trended for exposure, using population and dwelling house data. The adjusted record shows no trend in reported flooding over time, but there is significant decade to decade variability.
This study opens a new approach considering flood occurrence over a long timescale using reported information (and thus likely effects on society) rather than just considering trends in extreme hydrological conditions.
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This might also have something to do with it :
http://ampp3d.mirror.co.uk/2014/02/12/the-scandal-of-200000-homes-built-on-flood-plains/
Surely it does not require an academic to tell us that the denser the population the greater the risk of people being affected by a flood.
Might I also add that more urbanisation means more areas occupied by buildings, ashpalt and concrete, all of which are impervious to water penetration so maximize water shedding and increase flooding. Not too hard to understand.
Maybe, though, according to the Western Morning News, Ian Liddell-Grainger, Conservative MP for Bridgwater and West Somerset, ‘Environment Agency data showed dredging would have “considerably alleviated” the impact of flooding on the Somerset Levels.’
‘The MP said farmland had been submerged, homes flooded, businesses forced to close, families evacuated and wildlife wiped out in an area which used to be “one of the finest wildlife habitats in the country”’.
Read more: http://www.westernmorningnews.co.uk/Somerset-MP-continues-attack-smug-arrogant-self/story-20603848-detail/story.html
but… CO2
There is another interesting angle, which they don’t know about because they didn’t speak to their lawyers 😉
If you go to law school in ‘England + Wales’, you will learn how to do a few things re. sale of real estate – including obtaining the risk-rating of flooding in any given area. It turns out that no new land designated for [building] in England today is considered safe from flooding, because all the safe parts have long been build on. So yeah, I can see how that is tied to population growth.
There are other examples where weather / climate have nothing to do with it:
Floods are also ‘popular’ in Germany, so here is a little [factoid] I learned in the late 80s or early 90s: In Bavaria, they had reduced the areas where rain water could naturally drain by 90%, i.e. straightening of rivers, creeks, designating new land for building, land use change…
Probably most of those changes [occurred] after WW2, therefore climate change 😉
@jonesingforozone
Sure dredging may well have alleviated to problem but what everyone forgets is that the Somerset Levels (and the clue is in the name) are basically low-lying wetlands that have been reclaimed and still need to be pumped dry – much like the Fens of East Anglia and Lincolnshire.
Even so, the inattention to the UK lowlands is described as a “fiasco” by former members of the Environmental Agency. See Reliving the Environment Agency Flood Fiascos 1998-2013.
The amazing thing is that people are dumb enough to buy houses built on flood plains. I guess it’s the outcome to be expected from a dumbed-down education system.
Buying/building a house on a flood plain is just plain daft.
However, in the UK, this year’s winter floods were widely blamed on ‘climate change’ and not human stupidity. The greenies, goofies and general lefties are incapable of understanding the concept of occasional, severe weather events and that these occur with irregular monotony. In the case of last winter’s abnormal rainfall, probably once every century or two.
So, now there are at least two million houses in the UK which are unsaleable – almost at any price – because of the potential flood threat.
I suppose it is human nature for people to blame something like ‘climate change’ and not their own stupidity for the consequences of buying a house on a flood plain. To make matters worse, you have a government environmental agency stuffed full of green activists and/or career bureaucrats, where inertia, EU directives and Greenpeace dogma rule and provide an obvious cocktail for disaster.
Sigh………..
This new science amazes me.
Apparently building homes on an effing floodplain causes flooded homes.
Nobel prizes for everybody.
I think you can add in that people are wealthier and have more property today and are therefore more likely to report a flooding in order to make an insurance claim. Also that years ago people were more stoic and were unlikely to report flooding as they had fewer goods to lose and protected themselves by having tiled floors and fittings above flood heights.
Kitchens for example were much more basic than todays multi thousand pound constr8ctions which are very likely to get easily damaged and warrant an expensive claim.
Also, as has been noted, the less flood prone positions have long been occupied and what are left are likely to be vulnerable.
When you see developments in such places as ‘water street’ ‘floods end’ and ‘tides reach’ you should know that there has been a history of flooding. The authorities in Britain-including the Environment Agency-have no special powers to prevent building on a flood plain which are often attractive propositions for developers and potential residents as people like living near water.
tonyb
“In one of the most comprehensive studies of its kind, scientists have discovered that although the number of reported floods has gone up during the 20th and 21st Century, this trend disappears when the figures are adjusted to reflect population growth and increased building numbers over the same period.”
This report rather cuts the ground from beneath the feet of those who argue that more UK flooding is due to Global warming/Climate change/Weather wierding and is to be welcomed.
tonyb wrote
“When you see developments in such places as ‘water street’ ‘floods end’ and ‘tides reach’ you should know that there has been a history of flooding. The authorities in Britain-including the Environment Agency-have no special powers to prevent building on a flood plain which are often attractive propositions for developers and potential residents as people like living near water.”
This is quite true BUT local authorities DO have powers regarding zoning land for residential development. Cambridgeshire is flat and prone to flooding yet the local authorities not only allowed but actively encouraged development on disused industrial areas along the Cam ignoring local protests that the land was prone to seasonal flooding. More recently they approved further development at Trumpington meadows in the Cam valley. When (not if) these houses flood it will doubtless be blamed on global warming , climate change or weather wierding rather than greed and council ineptitude.
REALLY? Not what I read at the time, one of the main pumping stations was closed and not operating. I’d check the internet for more if you want?
Keith
My point was the EA do not have special powers to veto flood prone developments but perhaps ought to in order to compensate for land hungry councils and developers going for the easier, flatter, cheaper, more attractive but flood prone option.
tonyb
In the UK no home is further than two miles from a stream, river or the sea. We are a small island with a lot of running water.
I seem to remember the Aborigines once had a saying, “him white fella can’t manage the land”. Apply as required.
My house is 350ft above the nearest river yet the end of my lane is regularly flooded because they built 110 houses in the next field and put a five foot high concrete wall across my lane to fence in their back gardens. Then the Council come along and say they won’t adopt the lane as a road as it no longer goes anywhere and is prone to flooding.
Phew! That’s a relief. Since I live inland I can expect slower sea-level rises here.
My property has flooded twice in twenty years. The people who built the house must have been aware of this potential problem and built the house on short piles. The flood waters went under the property and did minimal damage.
If you build in an area prone to flooding, make sure the floor level is higher than the flood level otherwise you are asking for trouble.
Do I detect the merest faint beginnings of a sniff of a hint of a shuffle of a smidgin of movement away from catastrophism and towards more grown-up sensible logic and fact-based research? Just asking.
United states increase in flooding due urbanization.
http://pubs.usgs.gov/fs/fs07603/
eg,
“The effect of urban development in the last half of the 20th century on small floods is evident in Salt Creek, Illinois. With the exception of an unusually large flood in 1987, large floods have increased by about 100 percent (from about 1,000 cubic feet per second to about 2,000 ft3/s) while small floods have increased by about 200 percent (from about 400 ft3/s to 1,200 ft3/s). Nonetheless, even a small increase in the peak discharge of a large flood can increase flood damages”
just a quick google will flag up the increase of flooding due to urbanization around the world. Not surprising now that half the world lives in urbanized areas.
India
http://www.gifre.org/admin/papers/gjedt/URBAN-Vol%202(4)-gjedt.pdf
What is required is new housing on high ground.
Which therefore requires brownfield sites with electricity linkage and access roads.
Now, here’s the question: When a windfarm is decommissioned – is it a brownfield site?
(My guess is “Definitely,Yes” if you are the landowner).
This is a good piece of research repeating what many of us have been saying for years. Unfortunately it will be grabbed by the UK environment Agency as more excuses not to dredge rivers. It also does not apply to the dreadful flooding on the Somerset Levels where population levels have fallen over the past hundred years.and the flooding caused directly by not dredging the rivers for 20years or maintaining the sluice gates that remained closed thus keeping the flood waters in situ.