RIVPACS
Database & WFD Screening
WFD46
February 2007
EXECUTIVE SUMMARY
Background to research
RIVPACS is a model that predicts the freshwater macroinvertebrate fauna
expected to occur at a site in the absence of pollution. The four
current RIVPACS models are based on 835 reference sites from streams
and rivers through the United Kingdom. With the advent of the Water
Framework Directive (WFD) the concept of the ‘reference
condition’ has become explicit within the legislative
framework of the European Union. Reference condition has been
established as a quality standard against which assessments of
biological degradation must be compared. It is therefore essential that
Member States can demonstrate that the biological datasets used to
define reference conditions meet the criteria of the WFD. The RIVPACS
reference site dataset is therefore central to the definition of
reference conditions for macroinvertebrates in streams and rivers in
the United Kingdom.
The UK RIVPACS models were originally based on minimally impacted
sites. These sites were sampled over various phases of RIVPACS
development over some 20 years. There is therefore a requirement to
reappraise the levels of anthropogenic pressure acting at the RIVPACS
reference sites at the time of sampling and where necessary to identify
particular sites that fail to meet these new standards.
The Environment Agency, the Scottish Environment Protection Agency and
the Environment and Heritage Service are engaged in a European WFD
intercalibration process that is currently underway within several
Geographical Intercalibration Groups (GIGs). These Agencies therefore
need to gain full access to the RIVPACS dataset and its associated
pressure data to contribute to the process of setting common standards
for reference sites at a European level. As the data underpinning the
RIVPACS system is central to the setting of reference conditions for UK
streams and rivers, the UK agencies also require the RIVPACS dataset to
be available to the public so that their site assessments for WFD
monitoring are open and transparent.
Objectives of research
- To establish the ownership of the RIVPACS reference site
dataset
- To liaise with all stakeholders of the dataset to establish
unhindered access to the RIVPACS reference site dataset for the UK
agencies (in perpetuity)
- To deliver the RIVPACS reference site dataset to the UK
agencies and to the public domain in a readily accessible database
together will its accompanying physicochemical variables (both existing
and newly collated as part of this project), historical and current
anthropogenic stress data, and a range of calculated biotic indices
- To conduct an analysis of pressure data for the RIVPACS
reference sites and to identify any sites that fail to satisfy the new
WFD definition of reference condition.
- To summarise anthropogenic pressures acting at RIVPACS
classification groups and WFD System-A stream types.
Key findings and
recommendations
Ownership of the RIVPACS dataset resides with no single organization
and several different organizations consider that they own different
portions of the dataset. Formal permissions to release the dataset into
the public domain have been obtained from all twelve extant
organizations that have been identified as having funded various phases
of RIVPACS research. In addition, CEH/NERC has also agreed to release
the RIVPACS dataset to the public domain. Terms and conditions relating
to the end use of the RIVPACS dataset have now been established. The
RIVPACS database has been assembled in Microsoft® Access and
can now be downloaded from the CEH web site.
Anthropogenic pressure levels at all 835 RIVPACS reference sites have
been summarised by WFD system-A stream types, separately for WFD
Ecoregion 17 (Northern Ireland) and Ecoregion 18 (Great Britain).
Pressure levels have also been summarised by RIVPACS classification
groups and compared to appropriate biotic index values. Forty sites
(4.8%) out of the current 835 UK RIVPACS reference sites were
identified as potentially unsuitable across the four RIVPACS models
(Great Britain 33 (5.4%), Northern Ireland 4 (3.6%), Scottish Highlands
3 (2.7%) and Scottish Islands 1 (1.8%) – one site being in
both the Great Britain and Scottish Highlands models). Of these, 29
sites were identified as having either excessive organic or nutrient
pollution (or both) relative to other sites in their group, 8 had
excessive metals concentrations and 3 had unacceptably low flows. No
sites were judged to have unacceptably low pH. Steps should be taken to
either remove these sites from future models or to statistically
correct for their influence. No sites were judged to have unacceptable
levels of morphological degradation, thermal pollution, sedimentation
or communities adversely affected by non-native species.
The selection of potential new RIVPACS reference sites must now take
account of the WFD definition of reference condition. Any potential new
RIVPACS reference sites must be selected in consultation with the UK
agencies and be based on a thorough appraisal of environmental stresses
to ensure that none of these lie outside the appropriate range for that
stream type.
Keywords:
RIVPACS database, database documentation, Water Framework Directive
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£40.00, less 20% to FWR members.
N.B.
The report is available for download from the SNIFFER Website