SEPTEMBER 2008 Online 579 Geofile Mike Wynn PLUVIAL FLOODING IN KINGSTON UPON HULL AND THE EAST RIDING OF YORKSHIRE: A NEW BRITISH PHENOMENON Introduction Physical geography of the City drainage Kingston upon Hull (usually city Post war, Hull had many open referred to as Hull) is located on The area is no stranger to flooding. drains that were gravity-driven the north bank of the Humber The 1953 storm surge affected the and fed into the Humber at low estuary and surrounded by the East Yorkshire coast, and the old tide. From 1949 to 1975 this East Riding of Yorkshire. It is a town of Hull has always been system was replaced with small city of 243,589 people (2001), subject to flooding during combined effluent and storm water with major port facilities, exceptional spring tides. sewers that were emptied by two industries (including BP, Smith Consequently in 1980 a tidal large pumping stations at West and Nephew, Reckitts), presently barrier was built across the mouth Hull (32 cumecs) and East Hull undergoing regeneration, and acts of the River Hull to stop high tides (26 cumecs). The Bransholme area as a small regional service centre. entering the mouth of the river of the city has had a separate storm and flooding low-lying parts of the water drainage system since the The East Riding (Figure 1) is city. 1950s that pumps water into the made up of the chalk Yorkshire River Hull (Figure 3). Wolds and Holderness. The latter Over 90% of the city lies below is a large, low, undulating wet area high-tide level: some areas are Hull was considered to have a of boulder clay topography. built on reclaimed marshland, modern drainage system that could Piecemeal reclamation since the other areas (East Carr and Orchard operate at full potential until 2000, medieval period involved land Park) are below sea level; these low when Humbercare was drainage, and the drying out of the elevations mean Hull’s drainage constructed. This system was area has reduced the level of the system has to be pumped. To the completed in 2005, and consisted land. Springs in the Driffield area west of the city on higher ground of a tunnel connecting west Hull give rise to the River Hull, which are the settlements of Cottingham, and east Hull sewers to a new drains south through Holderness Anlaby and Hessle. To the north is sewage works at Saltend. However to the Humber in a broad flat Beverley. All these settlements the additional pumping capacity at alluvial valley. In its final few drain water into the catchment of Saltend (22 cumecs) led to a miles it passes directly through the the River Hull. reduction in the pumping capacity city of Hull. of both the other stations, and after further consideration the west Hull station was deemed Figure 1: Kingston upon Hull and the East Riding of Figure 2: Main areas of flooded roads and properties, Yorkshire Kingston upon Hull, 25 June 2007 Kingswood Bransholme R. Derwent Flamborough Orchard Park E. Carr Head Yorkshire Priory Road Wolds Bridlington Newland Driffield The Avenues River York Hull R. Hull Derringham Hornsea Holderness Market Beverley Weighton East City Docks Do Kingston upon Hull Ella centre ck Goole s Anlaby Park r Saltend be um H R he . H Spurn T um 0 4km 0 20km be Head Grimsby r Key Source: adapted from Coulthard et al. (2007) Boundary of the East Riding of Yorkshire GeoFile Series 27 Issue 1 Fig 580_03 Mac/eps/illustrator 11 s/s NELSON THORNES PUBLISHING GeoFile Series 27 Issue 1 Artist: David Russell Illustration Fig 580_01 Mac/eps/illustrator 11 s/s Geofile Online ©NELSON Nelson Thornes THOR 2008NES PUBLISHING Artist: David Russell Illustration September 2008 no.579 Pluvial flooding in Kingston upon hull... Figure 3: Simplified drainage network in Kingston upon Hull large areas of Orchard Park, Newland Avenue, the Avenues, Key Priory Road, East Ella, Anlaby Generalised direction of R. Hull movement in sewer network Park and Anlaby flooded. 250 streets were submerged (Figure 2). T Bransholme Transfer tunnel 90 of the city’s 105 schools were Cottingham WHPS West Hull pumping station damaged. EHPS East Hull pumping station WWTW Waste water treatment works In spite of the magnitude of the Willerby storm, key pieces of crucial Hull Drainage area for Bransholme WWTW sewage treatment and pumping infrastructure did not fail. station T Saltend Hospitals stayed open, the city Anlaby centre remained free from EHPS T T 0 4km flooding, most electricity did not WHPS fail, drinking water supplies River Humber continued to function and the Hessle telephone system operated. unnecessary, but retained for Hull’s drainage system could not The consequences emergency purposes, givingGeoFile a Seriesaccommodate 27 Issue 1 the amount of capacity of 62.4 cumecs.Fig Even 580_02 so, Mac/eps/irainwater:llustrator 11 drains s/s backed up and Personal the new treatment worksNELSON would THORNESoverflowed. PUBLISHING The City Council Water rising out of rivers and provide protection from aA 1-in-30-rtist: David Russedeclaredll Illustra tiona major incident at 09.30. sewers creates dangerous health year rainfall event. However the A month’s rain fell in 24 hours on conditions. Sewage and chemicals floods experienced in 2007 in Hull 25 June, swamping and may dilute in floodwater, but still and the East Riding were to be overwhelming the sewage pose significant health risks. One something different and unique in infrastructure, so water had man died, trapped in a drain he the UK. nowhere to escape to and flooded was trying to clear. low-lying districts of the city. June 2007 First, the water was in just a few Once the clean-up operation got streets and was only a minor under way, people’s lives were laid June 2007 was the wettest month inconvenience. It had entered out in their front gardens. House recorded in Yorkshire since 1882 some garages by 08.30 and floors had to be taken up, skirting (over 250mm) and May, June and children could not get to school, boards removed and plaster taken July were the wettest since records but then it rose into the air bricks off wherever it was wet or damp, began in 1760. On 25 June a around the bases of houses and and electrical wiring renewed. deepening depression (997mb) entered the properties. By 10.30, Dehumidifiers can take months to became slow-moving over the UK, water was 45cm deep in houses, at dry properties out, giving ample giving sustained heavy rain across which point it was reported people time for fungal spores to develop Lincolnshire, Yorkshire and the were told to buy their own which can affect old people and Midlands which led to widespread sandbags. When the water got to a those with allergies and asthma. flooding. Previous heavy rain (over metre deep, toilets overflowed into 80mm) had occurred on 14/15 the houses. People in bungalows Losses of personal and sentimental June, leaving soils saturated and had no higher floor to escape to or property can be very stressful for water courses inundated and move possessions into; they lost some people, and such flood events causing some localised flooding. everything. can even cause psychological Further rain occurred on 20/23/24 problems. Many people had to June. The rain on 25 June Saltend continued to operate spend months living in caravans commenced at 02.00 hours, lasting throughout, but both its electricity without proper sewerage or water until 23.30 hours, and totalled supplies feed into one substation, supplies. Lots of people had no 110mm. This was heavy and and temporary flood barriers had insurance to cover their losses; those sustained with an intensity of to be erected to protect the that did may well see their 6mm per hour from 08.00 to 17.00. substation. Bransholme station premiums rise or have problems The return period for such a storm operated at capacity but flooded on renewing policies. Not only did is 1 in 150 to 200 years. Local 26 June and the pumps seized, as house prices in the affected areas rivers rose, but the River Hull did the bearings were under 6m of fall, but once people move back into not overtop its banks. water. There was a great deal of renovated houses, they tend to stay Groundwater levels on the flooding across the city, and initial for at least five years, which slows Yorkshire Wolds rose by an estimates suggested there were down the local housing market. enormous 10 metres in 24 hours. 14,000 to 16,000 flooded properties (homes, gardens and garages) (15% The media focused on floods in On Sunday 24 June the of all households), with 6,500 South Yorkshire where there was Meteorological Office had issued a homes flooded. Large areas of possibly more drama, and fourth wet weather warning that standing water occurred elsewhere overlooked Hull. The council instigated the opening of a 24-hour in the city. In east Hull, leader referred to Hull as ‘the flood incident room that day. It Bransholme, Kingswood and East forgotten city’. was soon obvious on 25 June that Carr were flooded. In west Hull Geofile Online © Nelson Thornes 2008 September 2008 no.579 Pluvial flooding in Kingston upon hull... Agencies Figure 4: Flooding in the East Riding of Yorkshire, June 2007 The main cause of the flooding Key was initially put down to blocked Flooded East Riding gullies (which channel surface towns and villages Flamborough Head water into sewers). It was alleged Flooded East Riding Bridlington that there had been cutbacks in the farmland gulley-cleaning regime in previous years, but neighbouring authorities which had been more Driffield active in cleaning gullies still had floods.