Dwellings at risk in South East Canterbury District
In the Canterbury South East area there is a total of 658 properties at risk from rivers (taking the existing defences into account), 562 of which are at medium to high risk.
Table 8. Number of dwellings at risk from fluvial/tidal flooding in Canterbury South East
South East Canterbury is dominated by gently undulating farm-land situated on shallow, lime-rich soils. The underlying chalk is generally permeable to surface water, and its valleys are interspersed with springs and groundwater fed ephemeral watercourses.
The main ephemeral watercourse running through this ward is the Nailbourne, which flows into the upper reaches of the Little Stour; this watercourse anecdotally flows for around 6 months once every seven years. Recently they have been flowing more frequently than this, with groundwater emergence activating them in 2000/1, 2003, 2010, 2012, 2013/14, 2014/15 and 2015/16. Prior to 2000, the last significant flood event in the Nailbourne Valley was in 1960.
The villages along the course of the Nailbourne and Little Stour have historically been flooded from many sources. They have been directly affected by the watercourses, from rising groundwater and the associated emergence of springs, and from surface water runoff from the surrounding hills and valleys. In combination, these sources of flooding have led to further problems caused by the surcharging and backing up of the sewers.
Following the 2000/1 flooding, many improvements to increase the capacity of the channel and various culverts were made (including the construction of a diversion channel at Littlebourne). However, the need for ongoing maintenance of the watercourse and drainage infrastructure was highlighted during the winter of 2013/14, and further improvements to these watercourses will be necessary to reduce both the risk of flooding and its impact to the affected communities.
The NaFRA mapping for Canterbury South East (which shows the areas at risk from flooding with the defences in place) is shown in Appendix 10.
- Canterbury Surface Water Management Plan – Stage 1 (April 2012): Section 3.6
- Canterbury City Council’s Strategic Flood Risk Assessment (http://goo.gl/3OHSZn)
Planned flood defence works in the Canterbury South East area
The Environment Agency received additional funding from Central Government to assist with repairing the damage sustained to the catchment over the abnormally wet winter of 2013/14.
The various Risk Management Authorities also produced a plan to outline numerous short-term schemes than were delivered before the onset of winter 2014/15. Much of this short-term work was achieved with funding already available from central Government, along with additional contributions from Canterbury City Council, Kent County Council, riparian land-owners and the local Parish Councils.
A longer-term plan of schemes that will require additional computer modelling, planning and funding has also been produced; these schemes will be progressed over the coming years, with all of the Risk Management Authorities and affected communities contributing to the development of the plans.
A summary of the works undertaken by the various Risk Management Authorities is available at: