Flooding of the southern part of the North Sea occurred between 9000 and 8000 BP, when the rate of relative sea-level rise was on the order of 0.7 cm per year for the Dover Strait Region and 1.6 cm per year for the area north of the Frisian Islands, forcing the shoreline to recede rapidly. When relative sea-level rise decelerated after 7000 BP for the Belgian coast and 6000 BP for the central Netherlands coast, sediment supply by the tidal currents balanced the creation of accommodation space in the estuaries and other back-barrier basins. Consequently, the barrier started to stabilize, and the tidal basins and their inlets silted up. Between 5500 and 4500 BP, the Belgian coastal plain changed into a freshwater marsh with peat accumulation, and the same happened 500–1000 years later in the western provinces of the Netherlands. The E-W running barrier/back-barrier system of the Frisian Islands in the northern Netherlands stayed open until today, however, because of lower sediment supply.

The period between 4000 and 2000 BP was relatively quiet due to the strong deceleration of the rate of sea-level rise; peat cushions developed behind the barriers, which were straightened by erosion of the headlands. Major and often catastrophic flooding occurred in the Middle Ages, when the estuaries in the southwestern part of the Netherlands formed.

About 226 (± 15%) × 109 m3 sediment, mostly sand, is stored in the barriers and back-barrier basins of the Netherlands, 70% of which was deposited prior to 5000 BP. About 10% of the stored sediment is estimated to be of alluvial origin. Most of the sediment is derived by the erosion of the Pleistocene basement during recession of the barriers, but tide-induced crossshore transport from the North Sea forms an additional source for the barriers and back-barriers of the west-facing coast of the Netherlands.

The fluvial history of the northern Lower Rhine Embayment shows interplay of three main river systems: Rhine, Meuse and smaller rivers draining the central and northern part of Belgium.

The Pliocene and Early Pleistocene (pre-)Rhine and Meuse river systems had their conjunction in the southern part of the Roer Valley Graben between Aachen and Jülich. Despite slight differences in the heavy-mineral assemblages the lithological composition of the Pliocene deposits of the three river systems shows close resemblance and therefore they cannot be mapped separately. However, due to a marked change of the petrographical composition the Upper Pliocene and Lower Pleistocene deposits of the Rhine are easily recognised and as a result Rhine and Meuse deposits can be mapped separately upstream of their confluence.

The Lower Pleistocene deposits of Rhine, Meuse and the Belgian rivers show a clear interrelationship. They are bounded by two regional well-mapable unconformities and are preserved in from west to east changing lithostratigraphical sequences. Revision of the lithostratigraphical schemes in Germany and the Netherlands and the better defined lithostratigraphical position of Meuse deposits in Germany now strongly constrain the correlation of the various fluvial deposits. As a result existing reconstructions of the fluvial deposition and tectonic history of the southern Roer Valley Graben can be evaluated and re-adjusted.

It is concluded that the main course of the Meuse was aligned through the so-called East Meuse valley during the larger part of the Early Pleistocene. Available pollen data do not conflict with this conclusion. At the same time the Rhine ceased to enter the southern part of the Roer Valley Graben. Instead, the Meuse accumulated here a series of deposits derived from the East-Meuse valley. Simultaneously, the Belgian rivers filled available accommodation space in the Roer Valley Graben of the southern Netherlands. The conclusions are based primarily on the revised lithostratigraphical framework. In general they simplify the picture of fluvial and tectonic behaviour of the area.

Uplift of the Rhenish Massif can be demonstrated by means of the stream-made river terrace system that accompanies the Rhine river and its tributaries along their way through or within this part of the Variscan fold and thrust belt. The height difference between a former valley floor, especially that of the Younger ‘Hauptterrasse’ (Main Terrace), and the recent one allows to quantify the uplift by the amount of downcutting erosion. The uplift velocity increased just after the BRUNHES / MATUYAMA boundary, i.e. about 0.8 Ma B.R Since that time, a domal uplift of more than 250 m is documented in the eastern Hunsriick and in the south-eastern Eifel. The area of this maximum height anomaly is situated just between the East-and West-Eifel Quaternary volcanic districts. Thus, causal connections are supposed. The domai uplift is affected by normal faulting partly inherited since Tertiary rifting.

The Gelderse IJssel is the third major distributary of the Rhine in the Netherlands and diverts on average ~15% of the Rhine discharge northward. Historic trading cities are located on the Gelderse IJssel and flourished in the late Middle Ages. Little is known about this river in the early Middle Ages and before, and there is considerable debate on the age and origin of the Gelderse IJssel as a Rhine distributary. A small river draining the surrounding Pleistocene uplands must have been present in the IJssel valley during most of the Holocene, but very diverse opinions exist as to when this local river became connected to the Rhine system (and thereby to a vast hinterland), and whether this was human induced or a natural process. We collected new AMS radiocarbon evidence on the timing of beginning overbank sedimentation along the lower reach of the Gelderse IJssel. Our data indicate onset of overbank sedimentation at about 950 AD in this reach. We attribute this environmental change to the establishment of a connection between the precursor of the IJssel and the Rhine system by avulsion. Analysis of previous conventional radiocarbon dates from the upper IJssel floodplain yields that this avulsion may have started ~600 AD. Our results contradict earlier suppositions, based on interpretation of archaeological data and historical accounts, that the Gelderse IJssel is much older and originated as a canal, dug under supervision of the Roman general Drusus.

Shells belonging to the bivalve genus Corbicula occur commonly in Pleistocene interglacial deposits in NW Europe. These have usually been identified as C. fluminalis, a modern species described from the Euphrates river, although the veracity of this specific attribution remains equivocal. Corbicula has nowadays a southern distribution, and laboratory studies indicate that it is thermophilous. It is also tolerant of brackish water, one of several attributes that make this an effective colonizer.

In NW Europe, Corbicula is known from the Lower Pleistocene but is absent from the Cromerian Complex, occuring again in the three interglacials following the Anglian/Elsterian. It appears to be unknown from the last interglacial, except as derived fossils.

Based on field observations performed in 1999 and 2000, the exotic amphipod Dikerogammarus villosus is now well established throughout the navigable sector of the River Moselle in France. D. villosus co-occurs with Gammarus pulex, G. tigrinus and D. haemobaphes, another recent exotic species found in this tributary of the River Rhine. The maximal size of individuals of D. villosus collected (15.7 mm) is lower in the River Moselle than in other basins, where this species could reach up to 30 mm (Neseman et al. 1995). Nevertheless it represents the largest gammarids found in the French sector of the River Moselle. Other particular traits are its wide phenotypic plasticity, varying from a melanic to a striped form, and its predatory behavior. These particular traits may favour the establishment of this species on a recipient ecosystem. The occurrence of D. villosus was noted in the Alsace Canal and in the River Rhône, showing that its immigration across French hydrosystems is still in progress.