Faecal
pollution
ME-10
Marine
Environment & Coastal Zones
Pressure
1 Indicator
definition and unit of measurement
The
discharge and dumping of faecal material into coastal areas
in
tonnes equivalent per annum
(
or
per chosen critical time period when looking at the human health aspect
).
2 Placement
in the framework
5EAP:
Not
applicable.
Agenda
21:
Chapter
17
:
Protection
of the oceans, seas and coastal areas and the protection, rational use and
development of their living resources
.
International
conventions and agreements:
Reductions
of emissions of organic matter including sewage to waters are agreed in
OSPARCOM
(Oslo, 1972 and Paris, 1974)
,
HELCOM
(Helsinki, 1994)
,
the
London
protocol (1973) - to the Convention on the Intervention on the high seas in
cases of oil pollution casualties (Brussels, 1969) - on pollution by substances
other than oil
,
the North Sea
Declarations
(1984 onward)
,
the Rhine Action Plan
(1986)
,
Blue Plan
MAP
of the Barcelona convention (1975),
the Black Sea Action Plan
(1995).
EC
Urban Waste Water Directive
(91/271/EEC)
setting sewage treatment standards and time frames to achieve these for large
and medium sized population centres.
Ranking:
Core
ranking:
10
(29%)
Policy
Relevance:
10
(2.8)
Analytical
Soundness:
11
(2.7)
Responsiveness:
1
(2.9)
Most
appropriate related state indicator:
To
deal with the human health issue: Faecal material indicator (faecal
strep.
E coli etc.) concentrations in coastal waters, sediments and in
selected
bioindicator or food organisms
.
To
deal with the nutrient load:
Sediment
nutrient levels in urban areas.
3 Significance
Purpose:
•
Give politician
s/the
public
a picture of faecal contamination inputs to coastal waters and hence safety in
use for water sports, economic potential as tourist destination and by many
seen as sign of overall quality of their coast.
•
Give impression of faecal pollution as pressure on shellfish industry
.
•
Indicate nutrient and organic matter input from sewage as threat to marine
ecosystems, changing plankton biomass and species, with risk of bloom and toxic
species
.
•
If
coupled with state indicator, should show effectiveness of conventions,
legislation and investment in treatment
.
Relevance:
Faecal
pollution by man and beast can cause health problems from mild eye and ear
infection, to diarrhoea
and
serious infectious illness including typhoid. Despite of high awareness and a
considerable body of legislation, faecal pollution is still wide
-spread
in the coastal zone and of high public concern. It is estimated that bathing in
contaminated waters causes over 2 million cases of gastro
-intestinal
cases per annum
(Water
stress in Europe 1997, EEA and UNEP)
.
The
second main faecal pollution issue is that sewage is rich in nutrients and
organic matter which cause detrimental changes to bottom sediments near sewage
outfalls and contribute to eutrophication over much wider areas.
For
the past thirty years there has been a pronounced shift of populations into the
coastal zone with consequent increase
in
sites
where sewage enters the sea. On the other hand, large population centres have
begun to benefit from modern treatment plants, many with secondary, some with
tertiary treatment, bringing a marked improvement in urban water quality
standards which is set to continue to meet
urban
waste quality standards. Additionally the practise of dumping sewage sludge at
sea is being phased out and will be illegal after 1998. Overall one may talk of
a trend towards reasonable quality everywhere, with number of pristine areas as
well as number of very poor quality areas decreasing.
Regarding
nutrient load though, many scientists belie
ve
far
greater efforts are needed, with more nutrient removal from sewage to bring
overall European sea nutrient levels down to levels where foam blooms and red
tides are significantly reduced.
Linkages
to other pressure indicators:
Faecal
pollution is a cause of eutrophication. It is associated with development along
the shore, often with tourist intensity and tend
s
to be associated with other discharges such as heavy metals in urban areas.
Targets:
Most
targets known to the public are state indicator-related
(guideline
and imperative values of the bathing water Directive
-
76/160/EEC -
being
perhaps the best known and popularised through the Blue Flag award scheme
for beaches (1987 onward).
The urban waste water directive
-
91/27/EEC -
sets
targets of treatment and discharge quality depending on the receiving waters.
It is however up to national government to designate receiving waters as
“
sensitive”
(thus requiring tertiary treatment), not sensitive
(implies
primary treatment only) or not designating which generally implies secondary
treatment.
4 Methodological
description and underlying definitions
Underlying
definitions and concepts:
We
are trying to represent several aspects of faecal pollution pressures in one
indicator here. First it is the pressure of sewage pollution on human health.
Raw sewage entering the sea through an outfall is alive with bacteria and other
micro
-organisms.
While their immediate area or current path
“potency”
may be serious, soon they will die off and within days most will be ineffective
as disease causing agents. Thus a small polluted stream will only have a
localised effect relevant if the area is shellfish or bathing water, but
otherwise of little consequence from the health point of view. Also high season
pollution bursts caused
e.g.
by a caravan park with inadequate treatment facilities, may be followed by 10
months of excellent water quality. The second aspect of this indicator is the
longer term effects of organic matter and nutrients on the marine ecosystem.
Partially treated sewage may still be very high in nutrients, though from a
bathing water quality point of view it is acceptable. Thirdly faecal material
from both man and intensive agricultural operations like pig rearing are also
associated with antibiotics and heavy metals.
Faecal
pollution may originate from man or beast. There have been cases of high
salmonella levels due to near by sea bird colonies. Farm animals like sheep
s
or pigs carry the same sewage indicators as humans and will contaminate waters
in the same way. In rural areas animal faeces can be a significant localised
faecal pollution input.
Measurement
methods:
Health:
The composite load from 1
)
sewage discharge and treatment plants, 2
)
riverine input, 3
)
vessel inputs
(ships
own discharge and sewage sludge dumping) and 4
)
a factor for number of polluted small inflows in bathing or shellfish areas.
Faecal
pollution nutrient, organic input: composite load 1-3 above and a factor for
all small polluted inflows, irrespective if going into a bathing or shellfish
area.
Modern
coastal sewage treatment plants discharge monitoring data includes information
on organic content, and indicator bacteria counts/100ml. Main riverine
monitoring programmes are ongoing and vessel data is beginning to be gathered.
Small inflows are generally
not
tested.
Coastwatch Europe data suggests nearly two small inflows per kilometre shore as
European mean.
A
simple
monthly test in the bathing season of inflow quality in bathing and shellfish
areas would be cost effective, have direct public health benefits and serve the
pressure indicator needs.
Limitations
of the indicator:
Concerning
public health there is an ongoing argument on bacteria and viruses to measure
and monitoring methods. Unless one goes for very high monitoring expense there
could be a challenge about the accuracy of data used and its relevance to human
health risk.
Alternative
Definition:
One
will have to decide whether to invest in public awareness campaign to bring
home that a
reduction
of
faecal
pollution also brings benefits in nutrient suspended solid and heavy metal
reduction, or whether to treat this indicator as health issue only and separate
out nutrient etc. input as falling under another indicator. If the latter is
chosen, then the alternative definition may be: The health risk associated
faecal pollution input into the coastal and marine environment.
