Feniton and Devon-Wide Floods 13-15th August 2020

Contents

1. Introduction

The Flood Risk Regulations 2009 and the Flood and Water Management Act 2010 (the Act) have established unitary and upper tier local authorities as the Lead Local Flood Authority (LLFA) for their area. This has placed a number of responsibilities on the LLFA in relation to flood risk management and in particular Section 19 of the Act which states:

Flood and Water Management Act 2010: Section 19 – Local Authorities: investigations

On becoming aware of a flood in its area, a lead local flood authority must, to the extent that it considers it necessary or appropriate, investigate –
1. which risk management authorities have relevant flood risk management functions, and
2. whether each of those risk management authorities has exercised, or is proposing to exercise, those functions in response to the flood.
Where an authority carries out an investigation under subsection (1) it must –

publish the results of its investigation, and
notify any relevant risk management authorities.

Flood and Water Management Act (2010), S.19, c.29, London: HMSO

A ‘Risk Management Authority’ (RMA) means:

(a) the Environment Agency (EA),

(b) a lead local flood authority,

(d) an internal drainage board,

(e) a water company, and

(f) a highway authority.

When considering if it is necessary or appropriate to investigate a flood event Devon County Council (DCC) will review the severity of the incident, the number of properties affected and the frequency of such an occurrence. Devon’s Local Flood Risk Management Strategy clearly sets out the criteria to be used when considering a Flood Investigation Report.

Although not all of the locations in this report meet the significance threshold of 5 or more properties flooded, to ensure that the full extent of the flooding is appreciated and recorded it has been decided to include all locations brought to our attention which experienced any internal property flooding, and also other areas of particular concern.

In partnership with the other RMAs in Devon this report has been produced to comply with legislation and to determine the main causes of the flooding. It should be noted that in order to progress with their flood risk management function DCC has opted to develop this report further by considering the various actions that should be considered by the relevant RMA. DCC as the LLFA will continue to monitor the list of actions with all of the RMAs and will assist in the delivery where practical to do so.

Each affected area or group of smaller areas investigated within this report will have a number of recommended actions to be taken forward by the relevant RMAs or in some cases, by the landowner or local community action group. There are various levels of action that can be taken depending on the severity of the situation and the practical solutions available to reduce the risk of further flooding. The recommended actions will generally fall into one of the following categories:

Delivery of Quick win schemes: a solution that can be implemented quickly by the Risk Management Authorities or Local Authority at relatively low cost; some of these have already been completed as this report has been progressed.

Further investigation/research: Further investigations such as catchment studies and hydrological/hydraulic assessments to understand the flow rates and directional paths and evaluate the extent of flooding. These would provide evidence for future capital investment.

Development of Future schemes: Where immediate action is not financially viable or a solution not readily available then a larger scale flood alleviation scheme may be required. In such cases national funding would need to be secured together with additional contributions from others, such as local levy, local authorities and other third parties.

Landowner action: Members of the public who own land adjacent to watercourses have riparian responsibilities and therefore have a duty to maintain their section of watercourse to ensure there is no impediment of flow. Other works to protect their property may also need to be funded by themselves to ensure delivery within their timescales.

Community action: In some cases, it may be prudent for community groups to join forces and deliver and maintain their own local schemes. In some cases, this may generate further contributions from local levy or the LLFA.

This investigation report will provide a starting point, with suggested actions being further refined in the light of further studies and where possible, through further dialog with the affected communities.

Recommended Actions:

The purpose of this report is to act as a tool for all of the relevant RMAs to understand and appreciate the extent of flooding in their area and to consider and prioritise those actions relevant to their authority. Due to the extent of flooding, not only from the events covered in this report, the level of recommended actions far exceeds the budgets and resources available to enable them to be delivered immediately. Although we take all flooding issues seriously it should therefore be appreciated that some actions may not be progressed within the timescales expected by some residents or communities. Every effort will be made to progress the actions if and when suitable funding is obtained.

The recommended actions highlighted in this report will be used by the LLFA to monitor progress achieved by the RMAs.

2. Risk Management Authority Responsibilities

2.1 Recording Flood Incidents

LLFAs must now record flood incidents as part of their new duties. The information below shows the national guidance given as part of the Preliminary Flood Risk Assessment Spreadsheet submission to the EA, which outlines information to be collected by LLFAs.

Information the LLFA must now record:

LLFAs should record the following information from December 2011 Devon County Council (DCC) will record this on the DCC flood incident database:

Start Date
Days duration
Probability

Main source: Surface water runoff; Groundwater; Ordinary watercourses; Artificial infrastructure; Main rivers; The sea; No data
Main mechanism: Natural exceedance; Defence exceedance; Failure; Blockage or restriction; or No data
Main characteristics: Natural flood; Flash flood; Deep flood; Snow melt flood; No data
Significant consequences:
To human health (residential properties)

To economy (non residential properties)
To the environment (designated sites flooded)

2.2 Key Responsibilities

RMAs in Devon all have their own roles and responsibilities. The general RMA responsibilities in relation to flood risk and surface water management are outlined below:

The Environment Agency

The Environment Agency is responsible for managing the risk from the sea, Main Rivers and reservoirs and has a strategic overview role for all flood risk management, making it a key local partner for DCC, especially when managing the risk from combined sources and in the event of a large flood incident. The EA also provides a flood warning service throughout England and Wales in areas at risk of flooding from rivers or the sea.

Devon County Council as the Lead Local Flood Authority

Devon County Council as the Lead Local Flood Authority is responsible for overseeing the flood risk from Ordinary Watercourses, groundwater and surface water runoff. They are also responsible for consenting to works on Ordinary Watercourses and enforcing the removal of any unlawful structure or obstruction within the watercourse. And, as previously stated they must ensure that a flooding investigation is carried out by the relevant authority and publish a report. DCC must also prepare a Local Flood Risk Management Strategy and maintain a register of flood risk assets.

Local District Councils

Local District Councils are classified as land drainage authorities with discretionary powers under the Land Drainage Act, such as the implementation and maintenance of flood defences on ordinary watercourses. They also have powers under the Public Health Act to ensure the removal of any blockage within an Ordinary watercourse that is considered a nuisance. As a planning authority they are responsible for the preparation of development plans and making decisions based on planning policy.

Devon County Council as the Highway Authority

Devon County Council as the Highway Authority maintains the highway drainage system to reduce the amount of standing water on the highway. This is achieved by limiting the water on the roads and ensuring that they are kept clear of rainwater; including the maintenance of highway gullies and culverts.

The Highways Agency

The Highways Agency is responsible for managing, maintaining and improving the Motorway and trunk roads across England and any associated drainage and flood risk.

Land/Property Owners

Land/Property Owners that have a watercourse in or adjacent to their land have riparian responsibilities on that watercourse. This means the landowner must:

Let water flow through their land without any obstruction, pollution or diversion which affects the rights of others.

Accept flood flows through their land, even if these are caused by inadequate capacity downstream.
Keep the banks clear of anything that could cause an obstruction and increase flood risk, either on their land or downstream if it is washed away.
Maintain the bed and banks of the watercourse and the trees and shrubs growing on the banks and should also clear any litter or debris from the channel and banks, even if it did not come from their land.
Keep any structures, such as culverts, trash screens and debris grills, weirs and mill gates, clear of debris.

The LLFA must also take an overseeing role to ensure that all flood risk is being managed appropriately.

In small localised groundwater and surface water flooding incidents which do not reach the threshold level to trigger a flood investigation by the LLFA under Section 19, the Local Authorities will work in partnership to consider the appropriate action.

All RMAs have a duty to co-operate and to share information in relation to their flood risk management functions.

3. Flood Incident Summary Impact

3.1 Incident Summary

Between the 13th and 15th August there was Devon-wide flash flooding. A range of communities were impacted, most notably Feniton which had 10 properties experience internal flooding. Other areas affected include Crediton, Black Torrington, Ilfracombe, Okehampton, North Tawton and Whimple. In total, 22 properties (19 residential and 3 commercial) were reported to have internally flooded.

Table 3.1 (below) lists the towns and villages affected, together with the reported number of properties flooded. Each of the reported flooded locations has been identified on Figure 3.1, showing the geographical extent of flooding across Devon. It should be noted that the flooded locations have been reported in alphabetical order and not in any order of priority. Table 3.2 and 3.3 lists the depth of rainfall recorded from the Environment Agency’s rainfall gauge located at Ottery St Mary and Brookfield on 13th August 2020. These are the closest automatic rainfall gauges to the worst affected area at Feniton.

Table 3.1 List of towns and villages affected

Location	Number of properties flooded	Source of flooding
Black Torrington	1	Surface Water
Crediton	2	Surface Water
Feniton	10	Surface Water
Great Torrington	1	Surface Water
Halberton	1	Surface Water
Ilfracombe	1	Surface Water
North Tawton	3	Surface Water
Okehampton	4	Surface Water
Teignmouth	1	Surface Water
Whimple	1	Surface Water
Total properties flooded: 25

Figure 3.1 Map showing areas affected in flooding event 13th-15th August 2020

Table 3.2 Rainfall data recorded at Ottery St. Mary on 13th August 2020

Time	Rainfall (mm)
13:30	0.6
13:45	1.0
14:00	1.4
14:15	0.2
14:30	10.8
14:45	2.2

Table 3.3 Rainfall data recorded at Brookfield Farm on 13th August 2020

Time	Rainfall (mm)
13:30	2.8
13:45	1.2
14:00	1.4
14:15	13.3
14:30	1.5

3.2 Data and Information Collation

It should be noted that this report is only based on the information brought to the attention of DCC through its professional partners, the media and the public and where further investigation by the authorities have identified additional flooded properties. Therefore, it cannot be guaranteed to contain an exact or exhaustive list of individual properties or affected communities in the event between 13-15th August 2020.

3.3 Highway Infrastructure

During this event, significant surface water flooding affected the Highway network across Devon. Notable areas affected are detailed in the following list:

Princetown Road had approximately 600mm depth of surface water flooding
The A30 was blocked between Feniton and Fenny Bridges
South Western Railway had a replacement bus service between Exeter St David’s and Yeovil Junction due to flooding at Feniton
Fore Street in Okehampton suffered from flooding

The flooding event on 13th August was believed to be caused by extremely intense and localised rainfall that fell over a considerably short period. In many places, the drainage systems were overwhelmed by the large volumes of surface water runoff, causing them to function ineffectively and in some cases, surcharge. Typically, these highway drainage and sewer systems are not designed to cope with such high intensity short duration rainfall events.

4. Extent and Impact of Flooding

4.1 Feniton

Feniton was the area most adversely affected during this flooding event. In total, 10 properties (9 residential and 1 commercial) flooded internally in Feniton on 13th August 2020. Residents reported approximately 450mm (18 inches) of water coming into their homes, roads were blocked, and railway lines were under water. Station Road, Wells Avenue, Salisbury Close, Salisbury Avenue and York Crescent were some of the most affected areas in the village. The footpath in Salisbury Close acted as a flow route, filling gardens as the water made its way down to Salisbury Avenue. Some rear gardens, including garden offices and garages, were also flooded. One resident recorded 62.6mm of rain and a further 2.4mm overnight, making a total of 65 mm for the flooding event. This was as a result of the heavy rainfall landing on hard, dry surfaces and the drainage systems not being able to drain the water away quick enough.

4.2 Devon-wide

In addition to Feniton, a range of other communities across Devon were affected to a lesser extent, below the threshold for a formal Section 19 report. Many of these locations had isolated cases of flooding to single properties. These included Great Torrington, Halberton, Ilfracombe, North Tawton, Okehampton, Teignmouth, Whimple, Black Torrington and Crediton. Between these areas, 15 properties flooded in total, of which 12 were residential and 3 were commercial. The intense rainfall and short duration of the localised storm led to a large volume of surface water overwhelming the drainage systems.

5. Recommended Actions

The following actions in Table 5.1 are recommended for the areas affected in this chapter.

Table 5.1. Recommended actions for the Feniton area.

Action By	Recommended Action	How
General actions recommended for the areas featured in this chapter:
LLFA/ Property Owners	Increase community resilience.	To install Property Level Flood Resilience (PFR) measures where necessary in liaison with appropriate Risk Management Authorities. Devon County Council Flood Risk Management (LLFA) currently has a PFR Funding Scheme.
DCC Highways	To ensure efficient operation of highway drains and culverts.	Review and carry out maintenance in problem areas and consider providing additional gullies.
Parish/Town Council	Increase community resilience to affected community.	Ensure Community Emergency Plan is up to date. Support available from DCC and Environment Agency.
SWW	Ensure efficient operation of public combined and surface water sewers.	Continue maintenance regime and consider storm separation where appropriate.
Feniton
East Devon District Council	To ensure the delivery of the proposed flood scheme.	Continue to work towards implementing the proposed flood scheme.
Black Torrington
DCC Highways	To consider possible minor highway improvements identified that may aid in mitigating flood risk to properties.	To progress with works in line with available budgets, workloads and priorities.
Crediton
DCC LLFA	Identified in the local strategy as a high priority community.	Investigate possible flood alleviation works for the area in line with other priorities.
Great Torrington
DCC Highways	To consider possible minor highway improvements identified that may aid in mitigating flood risk to properties.	To progress with works in line with available budgets, workloads and priorities.
Halberton
DCC Highways	To consider possible minor highway improvements identified that may aid in mitigating flood risk to properties.	To progress with works in line with available budgets, workloads and priorities.
Ilfracombe
DCC LLFA	Consider options for mitigating surface water flood risk to areas identified in the Ilfracombe SWMP.	Progress with the Ilfracombe SWMP to finalise engineering options and prioritise/allocate funding and resources for flood alleviations works.
North Tawton
DCC Highways	To consider possible minor highway improvements identified that may aid in mitigating flood risk to properties.	To progress with works in line with available budgets, workloads and priorities.
Okehampton
DCC LLFA	Identified in the local strategy as a high priority community.	Investigate possible flood alleviation works for the area, in line with other priorities.
Teignmouth
DCC LLFA	Consider options for improving surface water flood risk to areas identified in the Teignmouth Drainage Study.	Progress with the Teignmouth Drainage Study to finalise engineering options and prioritise/allocate funding and resources for flood alleviations works.
Whimple
Environment Agency	Ensure delivery of proposed flood scheme.	Continue to work towards implementing the proposed flood scheme.

6. Next Steps

The next steps following this report will be for DCC as the LLFA to ensure that the recommended action tables in each chapter are taken forward by the identified responsible Risk Management Authority. DCC will prioritise the actions and monitor delivery through regular reviews, whilst working in partnership with the EA, District Councils, South West Water and the local communities affected.

There is an expectation from DCC of itself and its partners that all authorities involved will cooperate and work together to improve the flood risk in the vulnerable areas identified in this report by completing the recommended actions. As the LLFA, DCC has a responsibility to oversee the delivery of these actions.

Where minor works and quick win schemes have been identified, these will be prioritised and subject to available funding and resources will be carried out as soon as possible by the relevant authority or landowner. Any major works requiring capital investment will be considered through the Defra 6 year programme and other local funding opportunities

A review of the actions will be carried out by DCC as the LLFA in order to monitor progress and encourage delivery of recommended actions.