Geoscience Reference
In-Depth Information
example, Sustainable Urban Drainage Systems
(SUDS: CIRIA, 2001; Charlesworth
et al
., 2003)
now represent an alternative outlet for engineering
skills dealing with the source of flood runoff, rather
than at the scene of the resulting economic losses
or erosion damage downstream.
The rise in catchment consciousness varies
not just between the disciplines within
river management administration but also
geographically between different traditions and
jurisdictions, particularly in the interpretation
of environmental objectives and standards. For
example, a legislative opportunity was taken
to address historical regulatory loopholes when
transposing the WFD into Scottish law. The result
is that engineering works affecting Scottish rivers
now face more stringent evaluation and approval
procedures than those in England and Wales
(SEPA, 2010). Institutional arrangements for
fisheries management are also entirely different
in Scotland, with the result that more effective
physical habitat improvements have generally
been achieved by the Rivers and Fisheries Trusts
in that country. Further afield, the growth of
catchment consciousness has followed the cultures
and traditions of different countries (Newson,
2009); inevitably its uptake is influenced by the
scale and urgency of dominant water management
issues, such as improving irrigation for food
supplies or defending lives and livelihoods against
devastating floods (Newson 2009; Khan, this
volume). Nevertheless, IWRM has become the
generally accepted protocol for water development
funding.
suggests that various subtle long-term factors are
involved in triggering what might otherwise appear
as sudden changes, such as adoption of the WFD.
A steady change in political messages achieved
by public debate and influential news stories can
elicit a policy response; climate change is a good
example. Policy also determines the allocation of
resources to priority causes. River management
in England and Wales over the last 20 years has
sought a balance between humans and nature.
The inference is that, if the balance is not set
and adjusted in the light of compelling evidence
of the benefits gained versus the costs entailed,
the natural processes creating resilience essential to
human survival and development will be lost. For
freshwater ecosystems this allocation problem is
exemplified by disagreements over 'environmental
flows' in rivers and the needs of water resource
development or hydropower generation (Acreman
and Dunbar, 2004). Decisions about land use
and land management are even more politically
sensitive because they affect several policy sectors,
financial incentives, individual freedom and rights
(e.g. Everard and Capper, 2004). In a similar
fashion to ecosystems under stress, policy often
exhibits long periods of little or no change, followed
by rapid change usually in response to a political
opportunity or a crisis. Thus, the major themes of
river science informing policy-making in the UK
over the last 20 years have been:
(i)
deriving a better understanding of natural
forms and processes in river channels (Newson and
Large, 2006);
(ii)
assessing the importance of those variables
beyond the channel margins that influence natural
river ecosystem health (Figure 2.1);
(iii)
identifying interactions between key
components of the 'natural' system (habitats,
communities, sediment fluxes, flow storages,
etc.) and their provision of ecosystem 'goods and
services' (Everard, this volume);
(iv)
establishing the balance between the
provision of ecosystem goods and services and
the exploitation of rivers and their catchments
(Everard, 2009); and
(v)
defining the metrics for the above, suitable
for
Twenty years of influencing
policy and practice: improving
the evidence base and
knowledge needed for
managing 'natural' rivers and
catchment processes
Policy development and supporting legislation is
influenced by evidence and in many cases popular
support by the wider public. Historical analysis
use
in
policy,
regulation,
monitoring
and
