198
Normandy, the departments of Calvados, Eure
and Seine-Maritime, the ‘Conservatoire des
Espaces Littoraux et des Rivages Lacustres’,
‘Grand Port Maritime du Havre’ and ‘Grand Port
Maritime de Rouen’, municipalities and associations of local authorities or urban areas such as
Le Havre and Rouen (to develop their touristic
and urban capacity), as well as associations of
ecologists, farmers, manufacturers, hunters, fi shermen, etc. The various users are in a situation of
competition, each trying to promote/defend particular regulations and appropriate the estuarine
territory (Lozachmeur and Dauvin 2008 ). First of
all, the actors do not share a common perception
of the estuarine territory, and the accumulation of
regional, national and European laws, as well as
directives and territory management approaches,
does not favour the promotion of an overall vision
of the estuary. As a result, estuarine organisation
is currently understood in terms of sector-based
management. The present study aims to analyse
the contrast between this accumulation of sectoral
management approaches and a unique ecosystembased management process.
2
Main Characteristics
of the Seine Estuary
2.1
General Features
The Seine estuary was formed at the end of the
Tertiary, on a rocky substratum of Mesozoic age;
it extends from the Poses weir, 160 km upstream
of Le Havre, at the upstream limit of tidal penetration into the estuary, to the eastern part of the
Bay of Seine (Fig. 1 ). The estuary can be divided
into three main sections: the fl uvial (or upstream)
estuary, the middle estuary and the marine (or
downstream) estuary. The freshwater discharge
of the river is relatively small (400 m
3 .s
−1
), with
fl ood stage > 2,200 m
3 .s
−1 (autumn/winter) and
low fl ow stage < 100 m
3 .s
−1 (at the end of the
summer). The Seine estuary is situated on the
coast of the eastern basin of the English Channel,
and its hydrodynamics is strongly infl uenced by
the tide. The tidal range can reach 7 m during
spring tides in the downstream part of the estuary,
where a maximum turbidity zone acts as a
Fig. 1 Location of the Seine estuary and main sites mentioned in the text. TBS transverse border of the sea, LSI limit
of saltwater intrusion. T1 , T2 and T2 waterbodies defi ned for the implementation of the Water Framework Directive
J.-C. Dauvin
Normandy, the departments of Calvados, Eure
and Seine-Maritime, the ‘Conservatoire des
Espaces Littoraux et des Rivages Lacustres’,
‘Grand Port Maritime du Havre’ and ‘Grand Port
Maritime de Rouen’, municipalities and associations of local authorities or urban areas such as
Le Havre and Rouen (to develop their touristic
and urban capacity), as well as associations of
ecologists, farmers, manufacturers, hunters, fi shermen, etc. The various users are in a situation of
competition, each trying to promote/defend particular regulations and appropriate the estuarine
territory (Lozachmeur and Dauvin 2008 ). First of
all, the actors do not share a common perception
of the estuarine territory, and the accumulation of
regional, national and European laws, as well as
directives and territory management approaches,
does not favour the promotion of an overall vision
of the estuary. As a result, estuarine organisation
is currently understood in terms of sector-based
management. The present study aims to analyse
the contrast between this accumulation of sectoral
management approaches and a unique ecosystembased management process.
2
Main Characteristics
of the Seine Estuary
2.1
General Features
The Seine estuary was formed at the end of the
Tertiary, on a rocky substratum of Mesozoic age;
it extends from the Poses weir, 160 km upstream
of Le Havre, at the upstream limit of tidal penetration into the estuary, to the eastern part of the
Bay of Seine (Fig. 1 ). The estuary can be divided
into three main sections: the fl uvial (or upstream)
estuary, the middle estuary and the marine (or
downstream) estuary. The freshwater discharge
of the river is relatively small (400 m
3 .s
−1
), with
fl ood stage > 2,200 m
3 .s
−1 (autumn/winter) and
low fl ow stage < 100 m
3 .s
−1 (at the end of the
summer). The Seine estuary is situated on the
coast of the eastern basin of the English Channel,
and its hydrodynamics is strongly infl uenced by
the tide. The tidal range can reach 7 m during
spring tides in the downstream part of the estuary,
where a maximum turbidity zone acts as a
Fig. 1 Location of the Seine estuary and main sites mentioned in the text. TBS transverse border of the sea, LSI limit
of saltwater intrusion. T1 , T2 and T2 waterbodies defi ned for the implementation of the Water Framework Directive
J.-C. Dauvin