Daily graph and 24 hour forcast by the landowner Flood warning by Peter Colebrook of Marnhull (18 hours upstream of Bear Mead)

River height 197 at 1300, 14 Jul 2008

River state: Falling Medium.

Floodplain state 0% Flooded

River temp: 18°C River pH:    8.59 Last Flood: 17 Mar 2008

About the Dorset Stour Length: 100km, Catchment area: 1,300km2, Population: 400,000, Rainfall: 697-1131 mms/year, Flood season: Nov-Mar, Land use: 8% urban, 52% arable, 34% grassland, 6% other. Because much of the river's course is across clay soil, the river's waterlevel varies greatly. In summer, low water level makes the river a diverse and important habitat, supporting many rare plants. In winter, the river often floods, and is therefore bordered by wide and fertile flood plains. Eye Mead floodplain is pasture 1,000 metres wide, and 19 metres above sea level.

When the River floods Pictures of degrees of flooding at Eye Mead. 0% | 2% | 5% | 10% | 20% | 30% 40% | 50% | 60% | 70% | 80% | 95% Bear Mead, 1km upstream (right), not visible to photograph. Floodplain stretches 1km beyond (South) of River

The Dorset Stour floodplain, pictures centred on Eye Mead, SY 995-995, Eye Bridge left foreground, (see flooding progress). FL956. 9 Jun 2008. 1130 hrs. River height=182. Fields 0% flooded.

Past Records: Graphs (56 months) Numbers (56 months) Location Display by year Averages

Floods since July 03: Analysis of Floods 2003 none 2004 none 2005 Dec 3 2006 Nov 26, Dec 31 2007 Mar 6 2008 Jan 16, Mar 17 2009 2010 2011 2012 2013 2014

Report for 14 Jul: Rain: 0 mms River:197 Watertable:156

Forcast for 15 Jul: Rain: 24 hours River: 190 Watertable: 147

13 May - 10 Jun 2008                                                     No flood          No flood 11 Jun - 9 Jul 2008 10 Jul - 7 Aug 2008 No flood

Future rain: Rainfall predicted over the next 24 hours by the BBC Weather Centre. The river responds in 24 hours to heavy rain. The river falls equally quickly. Also see: 5-day forcast Location of Bear Mead: Bear Mead is about 5 miles North West of Poole Harbour, Dorset, England

BBC Weather Forcast for this area Work out the probable amount of rain that will fall, and how it will affect the height of the river. 5 Day-FORCAST Hourly-RAIN Hourly-CLOUD Hourly-TEMPERATURE Hourly-WIND Jetstream

Rule of Thumb: The difference between height of the Watertable (W) and River (R) decides the response of the River to Rainfall. If (W+60-R) is negative (dry ground), the River will hardly rise even after 30 mms of widespread Rain. If well positive (wet ground), the River may rise 250 cms in 24 hours for 30 mms of Rain. (W+60-R) usually becomes negative about early June and positive again about mid October, conveniently defining the dry season (summer) and wet season (winter). (W+60-R) has been observed with steady values in the range of +100 to -13. Present value of: (W+60-R)= +18 (dry)

A record of the Rainfall, Watertable and River Level of the River Stour at Bear Mead, about 2 miles West of Wimborne Minster, Dorset. Contact the author at for more information. see also: TIDAL TRENCH to control flooding. Unblocking, Tidying, Theory & early results and Results during flooding

This website tries to give simple answers to questions about flooding on the Dorset Stour at Bear Mead. Where is Bear Mead? See Location What do the fields look like when flooded? See the pictures below How high does the watertable have to be before the fields flood? 220 cms How much rainfall is needed to make the river flood? About 10 mms rain for every 10 cms below watertable of 220 When is it likely to flood? When the watertable is about 200 cms (but depends how much rain arrives in next 36 hours)

How quickly will it flood? About 24 hours after heavy rain starts. How quickly will the flood disappear? About 36 hours after heavy rain stops. How deep underground is the watertable? (220-L) cms where L is the watertable level given above Are there past records for water levels? Yes, see Numbers. Are there graphs of how past levels have changed? Yes, see graphs. How has the river flow varied since 1968? See Flow

State of Flooding on the River Stour

Bear Mead sometimes floods after prolongued rain in the winter. The flood plain is 1200 yards wide at this point. There are spot OS heights of 19 meters, in Field 3 and on the access bridleway "D". The nearest official calibrated river height scale is at Corfe Mullen Mill, 1.5 miles up stream, easily read from the A31. There is a well in Field 5, enabling the water table to be monitored. An unofficial scale has been placed in the river at Field 1. Rainfall is monitored daily at the Author's home, 2 miles away. The official calibrated river height scale at Julian's Bridge, Wimborne showed 16.9 metres when the river at Bear Mead indicated 150 cms, so Bear mead should flood when the official scale reads 18.6 metres (assuming the weir near Eye Bridge has no effect). Similarly, the scale at White Mill showed 21.4 metres, and should read 23.10 when Bear Mead floods. These pictures, taken in 2000, show what happens when the floodplain floods. They were taken from Eye Bridge, because it is not possible to get onto Bear Mead itself without a landing craft! The floods usually arrive quickly but also depart quickly, leaving the ground very soggy indeed. The depth of the water-table is a good measure of the "sogginess".

6. The Stour and floodplain.

8. Approach bridleway to Bear Mead, 15 Nov 2002.

7. Car park at Eye Bridge

Bear Mead 14 Apr 2004

River Stour at normal height in Spring (145 cms)

Compiled, formatted, hyperlinked, encoded, and copyright © 2004, John Palmer, All Rights Reserved.