2 Monitoring and maintaining the standard
of existing flood defence systems
17. The Agency's National Flood and Coastal Defence
Database indicates that there are 24,000 miles of flood defences
and 46,000 flood defence structures protecting properties in England.
The substantial increase compared to 2001 (when there were 11,000
miles of defences and 23,000 structures), was due to the inclusion
of coastal defences, better record keeping, and the transfer of
critical ordinary watercourses from local authority and internal
drainage board control. The Agency regularly assessed the condition
of flood defences by visual inspection and classified each defence
as:
- Very good:
Cosmetic defects which will have no effect on performance.
- Good: Minor defects
which will not reduce the performance of the asset.
- Fair: Defects that
could reduce the performance of the asset.
- Poor: Defects that
would significantly reduce the performance of the asset; further
investigation required.
- Very poor: Severe
defects resulting in complete performance failure.[20]
18. 5% of linear defences and 8% of structures remained
in very poor condition in April 2007, a proportion similar to
when this Committee last reported on this issue in 2002, although
the total number of defences and structures has increased considerably
over this time. The Agency's records indicated that assets on
critical ordinary watercourses acquired from local authorities
and internal drainage boards had been generally in a poorer condition
than other flood defences. There is, however, an absence of reliable
inspection data from the time when responsibility for their maintenance
was transferred to the Agency, which means that it is not clear
to what extent the transfer is the reason for the largely unchanged
proportion of defences in a very poor condition.[21]
19. Since the Committee's report in 2002, the Agency
had moved towards a risk-based approach to setting target conditions
for its flood defence assets and aimed to set target conditions
for each asset so as to achieve a balance between the costs of
maintaining the condition of an asset and the risk of its failure.
The target condition for individual assets varies depending on
the consequences of failure. Where the consequence of failure
is low, such as a defence protecting poor quality agricultural
land, the target condition could be as low as fair or even poor.
The Agency had also assigned assets to flood risk management systems,
which are groups of assets protecting a particular area from flooding.[22]
20. The Agency aimed to maintain 63% of flood defence
systems in a target condition in 2006-07 but failed to meet this
target.[23] On the basis
of the estimates from the Agency's area managers, only 46% of
high risk defence systems, which protect major risk areas such
as towns and cities, were in their target condition (see Figure
3). According to the Agency's review of the autumn 2000 floods,
less than 1% of flooding during that event was due to failure
of defences. The Agency suggested that the target condition of
some defences might therefore be over-specified.[24]
21. Nevertheless, the Agency's reports from its area
managers indicate that it had maintained a much higher proportion
of low risk systems (71%) and medium risk systems (62%) at their
target condition. It is questionable therefore whether the Agency
prioritises its maintenance work effectively. Two of the Agency's
seven regions in England (North East and Southern Regions) spent
less than 50% of maintenance expenditure on high risk flood defence
systems and the average spending on high risk systems by regions
across the country was only 55% (see Figure 4). A further
27% of maintenance expenditure had been on non-system specific
work, but in the absence of any reliable evidence, the Agency
could not show that the additional resources were devoted solely
to high risk systems.[25]
Figure 3: Percentage of high risk systems
at target condition in 2007
Source : National Audit Office analysis of Environment
Agency data
Figure 4: Proportion of maintenance expenditure
on high risk flood defence systems in Environment Agency regions
in England in 2005-06 and 2006-07
Source : National Audit Office analysis of Environment
Agency data
22. The Agency considered that the large proportion
of resources devoted to lower risk flood defence systems was partly
due to historical funding arrangements. In 2004-05, the previous
funding mechanism of capital grants on a scheme by scheme basis
combined with levies on local authorities raised by the Regional
Flood Defence Committees had been replaced by a single grant in
aid from the Department for Environment, Food and Rural Affairs.
Since then, the Agency had started to move towards prioritising
maintenance nationally based on risk and had sought to divert
a greater proportion of maintenance work towards high risk systems.
The proportion of planned expenditure on low risk systems in 2007-08
had reduced to 8% of the maintenance budget, with 18% on medium
risk and 74% on high risk.[26]
23. The Agency estimated that an additional £150
million a year is needed to bring flood defence systems up to
their target condition. On 2 July 2007, the Secretary of State
for Environment, Food and Rural Affairs announced that by 2010-11,
total expenditure on flood risk management would rise to £800
million. There is still scope to improve the cost effectiveness
of the Agency's maintenance work. The Agency was not able to show
that its maintenance teams were deployed efficiently or that they
focused their resources on high risk flood defence systems.[27]
24. The Agency's asset database should provide a
national picture of the state of flood defences, but it is cumbersome
to use and can be difficult to extract management data from easily.
The database could not handle reports of more than 300 defences
at a time. Only 80 local authorities use the database to monitor
the state of their non-main river assets. The Agency's inspectors
use the database to record inspection results, but local managers
have to rely on paper based records of maintenance work which
would need to be reconciled to data on the computer system in
order to check whether problems identified during an inspection
had been remedied.[28]
25. Some 9,000 miles (38%) of linear defences and
29,000 flood defence structures (63%) are owned and maintained
by third parties. Many such parties are private land-owners, who
have properties on the edge of rivers which form part of the flood
defence for an area. The Agency inspected all such assets, but
did not necessarily inform the owner of any defects which its
visits identified. The Thames River (Prevention of Floods) Act
1879 to 1962 enabled the Agency to compel owners on the River
Thames to remedy faults identified. The Agency had not, however,
determined whether similar statutory powers would be effective
elsewhere in the country. The Agency was nevertheless implementing
new procedures to notify third party owners, where they could
be identified. The Agency planned to put pressure on third parties
to comply.[29]
20 C&AG's Report, paras 2.1-2.2 Back
21
Qq 14-19; C&AG's Report, paras 2.4-2.5 Back
22
Qq 19-20, 93-96, 107; C&AG's Report, para 2.3 Back
23
The assets in a system are inter-dependent and a system meets
its target condition only if at least 95% of all assets in the
system meet their own target standard and no asset is more than
one grade away from its target standard. Back
24
C&AG's Report, paras 2.3, 2.7, 3.20; Qq. 22, Back
25
C&AG's Report, paras 2.9-2.10 ; Figure 11; Qq 71-74 Back
26
Qq 21, 68, 111, 117; C&AG's Report, para 2.11; Ev 17 Back
27
C&AG's Report, para 42.17; Oral Statement to the House by
the Secretary of State, updated statement on flooding in England,
2 July 2007; Qq 71-74, 97-98 Back
28
Qq 9, 75, 105-106, 138; C&AG's Report, paras 2.13-2.15 Back
29
Qq 69-70, 130-133; C&AG's Report, paras 2.6-2.8 Back
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