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Flood and Water Management Act, 2010
This document aims to
give an overview of the Flood and Water Management Act, 2010
from the point of view of the drainage engineer involved in the
process. The Department of the Environment, Food and Rural
Affairs (DEFRA) web site has several fact-sheets looking at different
aspects of the Act including
from the point of view of the
local authority and also gives details of the funding for local authorities.
Following the extensive
flooding during the summer of 2007, the government commissioned Sir
Michael Pitt to investigate the
causes of the flooding, the lessons to be learnt and to propose a way
The Pitt Report was completed in
June 2008 and the Flood and Water Management Act
was the government's response although the Act is largely only
and Wales. The Act covers a number of areas in addition
to those directly
involving drainage matters, including
administrative matters regarding water resources, water company
billing matters and special administration for failing
companies. The measures directly involving drainage include matters
regarding reservoir safety, giving the Environment Agency (EA) an
flood and coastal erosion matters, unitary and county councils
managing local flood risk and encourage the use of sustainable
drainage systems (SUDS)
for new developments. These measures with the
exception of those involving reservoirs will be examined in more
The Flood Risk
were made to address the requirements of an EU
directive and set in train many of the requirements of the Flood
Management Act with respect to flood risk management.
History of SUDS
The run-off from a
natural catchment depends on a number of factors such as topography,
type, the existing moisture content of the soil and so on. A
natural catchment, however, tends to act like a sponge, rainfall
falls on the ground and vegetation
and the majority is soaked up,
some to be gradually released over a period of time. In contrast an
urban area with a 'traditional' drainage system significantly
the water entering the ground and greatly increases the peak flow
entering the local watercourse. To counter this, for many years
have frequently been incorporated into new
development to reduce the peak flow so as not to cause overloading
to, and flooding from, the local watercourse.
design of a typical 'balancing pond' means that relatively low
intensity rainfall passes through the pond with little attenuation
and of course
the problem of a reduced amount of water entering the
ground remains. This means that for a large catchment, the river
still suffers from increased peak flows
during long, relatively low
intensity storms which are the types of rainfall likely to result in
flooding in this type of catchment. There is also likely to
reduced flows during dry weather. It is to try to combat these
problems that the overall SUDS concept has been introduced. SUDS aims
to mimic the natural
drainage of a catchment by reducing and slowing
down the run-off from a site. The SUDS techniques available include
green roofs, soakaways, rainwater harvesting,
infiltration trenches, filter strips, rain gardens, filter drains,
swales, detention basins, wetlands and retention ponds.
The SUDS approach was
originally developed during the 1990's, drawing on many
emanating from the United States and Sweden, although many of the
individual techniques had been in use for some time before that. From
the engineers point
of view, guidance was made available by the CIRIA
publications covering design, in 2000 and best practice in 2001.
These were consolidated and updated with the
publication by CIRIA of
the 'SUDS Manual' in 2007. Although at the time that the Flood and
Water Management Act reached the statute book some progress towards
the wider use of SUDS had been made, progress was slow. It was
generally believed that the concept was held back by the absence of a
suitable body to adopt and
maintain the SUDS infrastructure.
Provisions of the Act
As mentioned above, the
EA is to have an overview of all coastal and flood risk management
develop, maintain, apply and monitor” a strategy for
flood and coastal erosion risk management in England. In Wales, Welsh
Ministers will carry out this function.
The EA must also establish
Regional Flood and Coastal Committees (RFCCs) who will take over the
role of the existing Regional Flood Defence Committees but with
additional remit of coastal erosion. A lead local flood authority
(the unitary or county council for an area) must develop, maintain,
apply and monitor a
strategy for local flood risk management in its
area which will cover surface runoff, groundwater and ordinary
watercourses. The RFCCs will guide the EA flood
and coastal risk
management activities and will also assist in scrutinising local
authority's risk assessments, maps and plans. The lead local flood
will investigate incidents in its area to identify the
relevant flood risk management body. They will then inform the
responsible body of the results of their
deliberations. They will
also maintain a register of structures or features which are
important regarding flood risk. The Act also gives the EA power to
levy for a lead local flood authority regarding flood and
coastal erosion management.
Drainage approving bodies
will also be established and these are to be the unitary or
county council for the area. The minister,
however, has the power to
appoint a body to all areas or one area in preference to the unitary
or county councils. The drainage arrangements for projects of
national importance will be approved by the Infrastructure Planning
Commission. It should be noted that county councils in particular do
not have a great depth
of knowledge of drainage matters and this lack
of experience will be difficult to address in the short term.
National Standards for
SUDS, covering design, construction and maintenance is to be
introduced and this is
currently in preparation and will be published
by the minister for consultation in due course. The National
Standards are said by DEFRA to “allow for local
conditions to be
taken into account” which presumably includes such things as ground
conditions. In could be imagined that the National Standards will
heavily on existing guidance such as the 'SUDS Manual'.
The Act introduces a
requirement for the approval of the surface water drainage systems
for most types of construction work including patios. Approval is
before commencement of construction work. Obviously the act
will need some interpretation, particularly regarding patios and the
minister has power to vary the
definition. The Town and Country
Planning (General Permitted Development) (Amendment) (No 2) England
Order 2008 has already placed restrictions on the paving
gardens which can in some circumstances significantly increase the
paved area connected to the drainage system built to serve the road.
Growth in this
paved area would increase the flows in the highway
drain or public sewer so contributing to local flooding and probably
ultimately to the flooding of watercourses.
It is interesting to note
that section 163 of the Highways Act, 1980 also contains powers for
the highway authority to stop water being discharged onto the footway
of the highway. Applications for drainage approval under the Flood
and Water Management Act, will if appropriate, be combined with the
application for planning
permission or if planning permission is not
required can be applied for independently.
Paragraph 16 of schedule
3 of the Act amends the Water Industry Act 1991 by adding section
106A which changes the right to discharge
surface water to sewers.
Section 106 of the 1991 Act originally gave adjacent property owners
the right to drain foul and surface water to a sewer. This was
subsequently amended by the Water Act, 2003 to allow the water
company to refuse this if it was felt to be “prejudicial” to the
sewerage system. This power has
been applied with varying degrees of
enthusiasm, in some cases to the extent that it was blamed by
developers for stopping all development (including redevelopment)
over wide areas. The new section 106A says that new developments may
now only discharge surface water to the sewer if the site's drainage
system has been approved
under the Flood and Water Management Act.
The power to refuse connection if the surface water flows were deemed
to be prejudicial to the sewerage system is now
also removed. This
represents a slight improvement, as far as developers are concerned,
over the previous situation.
The approving body may
approve or reject an application or approve with conditions. The
will have a duty to adopt any new drainage system
which meets certain criteria including, that it was constructed in
accordance with national standards, that it
has been constructed in
accordance with the approved plans and that it is a sustainable
drainage system as defined by the minister. A non-performance bond
a requirement for an agreement to adopt to ensure that local
residents or the adopting authority are not left with an
unsatisfactory system. Sustainable drainage
systems can include
permeable roads although if these are to be adopted by the highway
authority, that part would not be adopted by the Approving Body. The
Approving Body is not under an obligation to adopt a drainage system
which serves only a single property but may adopt a SUDS system that
it does not have a
duty to. Presumably, in this case, an appropriate
commuted sum to cover future maintenance costs would be appropriate.
Once adopted, the approving authority
is under a duty to maintain the
drainage system in accordance with the national guidelines.
Part of the Act relating
to the EA and the local flood authorities developing strategies for
risk management was implemented from 1
October 2010. It is expected that the remainder of the Act will be implemented in April 2011 but that the SUDS provisions will be delayed until late 2011
or in 2012.
A large part of the
country is covered with impermeable soils meaning that some SUDS
techniques involving infiltrating the rainfall into the ground are
practicable and this significantly reduces the options available.
It should also be borne in mind that inappropriate SUDS techniques
used with impermeable soils
in the wetter parts of the county such as
Wales are only creating the flooding problems of the future.
The provisions of the Act
are being introduced as the
government announces that local
government and DEFRA are facing cuts of 28% and 29% respectively over
four years so it seems very likely that the measures will
funded. These cuts mean a reduction of £110m in planned capital
expenditure on new flood defence over the four years. DEFRA say, however, that
the Act will
be funded and that they will raise the local levy
to bridge the funding gap. In addition the government feels that
there will be savings from the
transfer of private sewers
the water companies since local authorities will no longer be
involved in resolving problems in that area.
envisages that the approval and supervision of the
on site will be self financing, being paid for by the fees paid by
developers. The minister is to make regulations on the level of fees
In the first few years
the adopted infrastructure
will be new and should be in good
condition and so will not require large amounts of capital spending.
There will however be a requirement for ongoing maintenance.
presumed that a maintenance period will be a condition of the
adoption agreements although we will have to wait until the national
standard for SUDS is
published to confirm this. Maintenance periods
are usual for the adoptions of sewers under section 104 agreements
and for new highway under section 38 agreements.
A maintenance period
will, again, further delay the need for spending on maintenance by the local flood authority.
Many people feel that the
unitary and county councils lack experience
in SUDS and drainage
matters in general and although training can be given, it will be
difficult to make up the deficit in experience.
The mandatory use of SUDS
techniques in the surface water management of new
sites together with
the adoption and maintenance of these features is a very worthwhile
exercise in terms of the reduction of flooding. It will however take
years to have an appreciable effect on flood risk.
As outlined above, the
Act gives the EA and the lead local authorities the duty to make and
apply flood risk strategies but without proper funding to investigate
flooding and carry out works, this is largely meaningless.
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Last Modified 17 January 2011.