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Marine Pollution Bulletin 50 (2005) 486–488

Correspondence

Implementing the European Water Framework

Directive: The debate continues . . .

The implementation of the European Water Frame-

work Directive (WFD) includes development of a series

of concepts, terminologies and tools which create somecontroversy within the scientific community (see Borja

et al., 2004a,b; Simboura, 2004). One of the potential

controversial issues relates to the matrices and elements

which should be addressed, in determining the physico-

chemical status within European transitional (estua-

rine) and coastal waters. Hence, some authors (see

Crane, 2003) claim that not only waters, but sediments

should be incorporated in the assessment of such astatus.

Recently, Borja et al. (2004c) highlighted the

problems which arise when a methodology for the inte-

gration of water, sediment and biomonitors was pro-

posed. This contribution has produced a series of

scientific discussions, via e-mail with the first author

(AB); the most relevant is that from the second (HH),

summarised here.

1. The problem in combining elements

Both the Working Groups for the Implementation of

the WFD and scientists in the Member States are dis-

cussing the integration or combination of biological

parameters (metrics, based upon phytoplankton, macro-algae, benthos and fishes), which are more useful in

assessments than any specific biological parameter of

scientific relevance. However, taking into account the

‘‘one out—all out’’ principle of the WFD, this shows

the danger of ending up with average environmental sit-

uations, where ecological problems may be levelled out.

It is important that the scientific basis which governs the

integration of parameters is sound and accepted. HHhas argued that, when integrating or combining para-

meters or metrics, the poorest argument for such a lev-

elling-out process could be that we cannot end up in a

worse ecological state where taxpayers could ask: �didwe waste the money we spent on environmental improve-

ments in the past?� such that the outcome of the assess-

ments could easily be biased by non-scientific reasons.

0025-326X/$ - see front matter � 2005 Elsevier Ltd. All rights reserved.

doi:10.1016/j.marpolbul.2005.01.002

This argument is reasonable and extends throughout

Europe. The problem in monitoring different water

bodies is to establish an �objective� method to assessthe quality of a water body. AB argues that the WFD

describes different approaches in determining quality

but, in some cases, a single variable on its own could

classify a water body as �bad� (for example). Thus it

may be practically impossible to achieve a �good� statusin many water bodies.

2. Simple and pragmatic?

One concern, commented by HH, is that the kind of

output now produced in the implementation process is

not one that the WFD requires. The goal is that we

should try to make monitoring, evaluation and method-

ologies in determining status as simple as possible. In the

chemical monitoring and assessment process of the

WFD, is it necessary to record the reaction of the whole

suite of inter-linked compartments, or is it sufficient todeal only with the one which is closest to a pressure? Thus,

do we need to monitor e.g. cadmium in all compart-

ments (water, suspended solids, sediments, biota), when

we want to record the success of a reduction measure?

Would it not be sufficient to measure only in that com-

partment, which: (a) is best suitable; (b) reacts initially;

and (c) is sufficiently available? This corresponds, in a

way, to the procedure adopted in operational biologicalmonitoring, which investigates the element of quality

which is most susceptible to a certain pressure.

Possibly a pragmatic approach is the most suitable.

One of the problems, when implementation of the

WFD has to be undertaken in a country with scarce re-

sources (e.g. some of those recently incorporated to the

EU), is to use only the available resources and no more.

In complicating the monitoring and implementation ofthe WFD, the cost of the status assessment could be-

come prohibitive.

3. What comes first, biological or physico-chemicalelements?

We agree that the WFD is a powerful analytical and

managerial tool, for combating distinct environmental

Correspondence / Marine Pollution Bulletin 50 (2005) 486–488 487

problems in the aquatic world. HH has commented:

‘‘Identify the problem (as in Annex II of the WFD),

classify it (as in Annex V) and, combat it (Article 11)

when it increases or surmounts the established thresh-

olds (Article 5)’’. The function of the biological investi-

gation is to demonstrate whether a contamination orphysical activity affects the biological elements to an

unacceptable degree. AB prefers the approach: ‘‘Study

the biological elements in order to detect any dysfunc-

tion in the ecosystem; if there are changes, then study

the remainder of the compartments of the system. Then

combat the problem’’.

What would be the sequence of chemical work for

WFD purposes? When a potential problem (e.g. a chem-ical) enters a water body, these usually disappear into a

�black box�of bio-geo-hydro-chemical processes which fi-nally may affect the biota. Is it necessary to observe what

happens in this �black box�, or is it sufficient to note thatit has reached a certain concentration which leads to an

observable but (un)acceptable threat to water life? Is it

necessary to observe the whole chain of evidence (which

normally acts in qualitatively and quantitatively com-plex processes), when our primary interest is simply to

identify an INPUT problem?

If you have a clear input of pollutants, this approach

could be correct. However, if this pollutant does not pro-

duce clear evidence of alteration could we assume that

there is no effect, or that it might have been transported

out of the system? What happens if there are no inputs,

but there is a polluted sediment (deposited, for example,some 60 years ago) affecting the benthic communities?

This example is relevant in the Annex II process, and

should be clarified under the investigative monitoring

(see Annex V). On the other hand, the Annex V explains

the monitoring plans for water should be undertaken

‘‘. . . to provide sufficient data for a reliable assess-

ment . . .’’, meaning the minimummonitoring frequencies

given in the WFD, could lead to a lack of adequate data,due to the variability of this particular compartment. In

this case, possibly other compartments (sediment, bio-

monitors) can act as a �snapshot� of an integrated period,estimating the need for information from these compart-

ments in order to avoid the problem of the variability.

In the event that the biology does not react as ex-

pected, chemical classification based upon ecotoxicology

can be undertaken, but this approach may be insufficientwhere it ignores the combined effects of chemicals on

organisms. Nonetheless, it is better than nothing at all.

Ecotoxicology is the response of a single species to pol-

lution, but the WFD addresses the whole ecosystem.

4. Sediment

An integrated bio-geo-hydro-chemical approach in

monitoring and assessment may work best only in very

clear situations, where there is a strong pollution signal.

As an example, OSPAR tries in every assessment to com-

bine the results of the different sources (water, sediment,

biota) but it always fails in the contaminated �average sit-uation� which is, on large spatial scales, the normal case

by far. For any particular site, trends may be identified inwater but not in sediments; or in another case a signal

may be obtained for the biota but not for the surround-

ing sediment, and so on. There is a permanent search for

a measure which might represent the truth. Where there

are difficulties in determining the trends, this may be be-

cause of such high variability. It is easier to identify clear

trends in sediment and biomonitors, following a pollu-

tion episode or a period of water treatment.There may be concern with introducing, on a routine

basis, sediment and biota measurements into WFD

monitoring, instead of water or suspended solids. Sedi-

ment and biota could be important when there is low

turbidity in the water, but this may not be enough. It

would be a pity to end up in a situation with nothing

really fits together, as in many traditional chemical mar-

ine monitoring.A non-sedimentologists view of sediments as being �a

calm depository� may also be misleading. While seasonal

signals in contaminant concentrations can be observed,

after substances have entered the sea bed a large variety

of physical and chemical processes take place, depend-

ing upon the availability of reactive material (e.g. clays,

organic matter), the degree of reactivity (e.g. Redox po-

tential), physical properties (e.g. porosity, temperature,deposition rate or even erosion), and biological activity

(e.g. degradation, bioturbation), etc. Thus, within sedi-

ments, the same degree of spatio-temporal variability

can be observed as in water and organisms. Such vari-

ability can be monitored; however, it is normally ig-

nored, because of simplistic concept on sediment

behaviour. Borja et al. (2004c) consider that the use of

water and sediment is complementary.

5. Encouraging the debate

The objective in publishing the comments and pro-

posals in Borja et al. (2004c) was to produce a discus-

sion, and to encourage the scientific community to

explore improved solutions in the implementation ofthe WFD. This scientific debate should remain open,

and we must continue to assess the ecological status of

European waters in a pragmatic, rational and scien-

tific-based approach, achieving a broad consensus be-

tween scientists, policy-makers and stake-holders.

References

Borja, A., Franco, J., Valencia, V., Bald, J., Muxika, I., Belzunce,

M.J., Solaun, O., 2004a. Implementation of the European Water

488 Correspondence / Marine Pollution Bulletin 50 (2005) 486–488

Framework Directive from the Basque Country (northern Spain):

a methodological approach. Marine Pollution Bulletin 48 (3–4),

209–218.

Borja, A., Franco, J., Muxika, I., 2004b. The Biotic Indices and the

Water Framework Directive: the required consensus in the new

benthic monitoring tools. Marine Pollution Bulletin 48 (3–4),

405–408.

Borja, A., Valencia, V., Franco, J., Muxika, I., Bald, J.,

Belzunce, M.J., Solaun, O., 2004c. The Water Framework

Directive: water alone, or in association with sediment and

biota, in determining quality standards? Marine Pollution

Bulletin 49 (1–2), 8–11.

Crane, M., 2003. Proposed development of sediment quality guidelines

under the European Water Framework Directive: a critique.

Toxicology Letters 142, 195–206.

Simboura, N., 2004. Bentix index vs. Biotic Index in monitoring: an

answer to Borja et al., 2003. Marine Pollution Bulletin 48 (3–4),

404–405.

A. Borja

AZTI Foundation

Marine Research Unit

Herrera Kaia, Portualdea s/n, 20110 Pasaia, Spain

Fax: +34 943 004801/004800

E-mail address: aborja@pas.azti.es

H. Heinrich

Federal Maritim and Hydrographic Agency (BSH)

Planning and Co-ordination of Environmental Monitoring

Head of Section (M51)

Bernhard-Nocht-Str. 78

20359 Hamburg

Germany

Fax: +49 40 3190 5000

E-mail address: hartmut.heinrich@bshde