The River Regge (the Netherlands): from meandering river to canal and back

The rivers Regge, Dinkel and Dommel are the case study sites for REFORM in the Netherlands. The Regge has been heavily regulated during the 19th and 20th century. Since 2000 a river restoration plan is being implemented step by step.

The Channelised River Regge. Photo: Piet Verdonschot

The river Regge basin is part of the much larger transboundary River Vecht basin situated in Germany and the Netherlands. Until 1848 the river Regge (The Netherlands) was a free and widely meandering lowland river. From 1848-1879 the first meanders were cut off to facilitate shipping, and in the periods 1894-1914 and 1929-1935 the main course of the Regge itself was channelized. Following that, until the 1950s further straightening took place on the main river, and between 1960 and 1980 most side streams were channelized for agricultural development and flood control. The previously meandering river changed and became a canal embedded in narrow shores, the riparian zone cleared and was subsequently surrounded by maintenance paths. In the terms of the Water Framework Directive the Regge is a “Heavily Modified Water Body.”

The river Regge basin encompasses about 841 km2 and is situated in between an eastern and a western glacial hill ridge. The eastern hill ridge feeds a number of small upper courses. The Regge descends from about 50 m to only a few meters above sea level. The basin can be divided in two areas: the upstream fringe and the remainder of the catchment.

The Regge basin has between 700,000 and 800,000 inhabitants, most of which live in the upstream fringe of the basin where there is a ‘line’ of cities (15% of the basin is urban).

 

 

Hill ridges east and west of the river Regge valley. Photo: Piet Verdonschot

The remainder of the basin has an increasingly interwoven combination of agriculture (61%), recreation and tourism, villages, and both wet and dry near-natural undeveloped areas (24%). There are about 3,500 farms (mainly cattle ranching on grassland, but also pig and arable farming). To sustain agricultural activities, the groundwater is maintained at least minus 80 cm below the surface level and in urban areas at least 150 cm below. Agriculture extracts more than 20-25 million cubic meters of groundwater while industry uses about 1 million and drinking water companies about 50 million cubic meters per year. In very dry periods the greater part of the discharge (up to 60%) in certain streams is in fact sewage plant effluent produced by the large urban areas. The original hard wood forests were felled in the 19th century, and the extensive peat reserves were exploited to supply households and industries with fuel. Only small parts of peat land still remain, and much of the present forest in the Regge basin was planted in the early 20th century. More than 95% of all streams are channelised.

River Regge basin. Left: year 1660; Middle 2000; Right 2025. Photo: Piet Verdonschot

Restoring the Regge

In 1998 the Waterboard of Regge and Dinkel, the Government Service for Land and Water Management (Dienst Landelijk Gebied) and the Province of Overijssel together presented the Regge Vision. Ideas for flood prevention and improving the ecological status of the river Regge were outlined thereby starting the so-called Regge Restoration project. The main aim is to create a dynamic and resilient river system to improve water quality and encourage natural flood protection. The use of parts of the river valley for water retention (new inundation zones) allows for the development of ‘new’ natural river floodplain areas, which also serve to connect different isolated nature reserves. Better opportunities for farming, recreation and urban development can also be secured as a result. The first restoration projects began in 2000.

River Regge restoration. Left: connected meander; Right: aerial view. Photo: Piet Verdonschot

Regge as research area for FP7 projects REFRESH and REFORM

As part of the FP7 project REFRESH, some shaded and unshaded streams within the catchment were surveyed for more than one year to establish temperature-shading relations along the European Atlantic coast. Within REFORM the river Regge itself is part of the WP4 paired catchments study. The case Regge targets a river restoration measure, connecting former meanders and giving space for flooding, and will be compared to two other comparable catchments with different restoration measures: the river Dinkel, another tributary of the River Vecht, which is near-natural and the restoration only consisted of bank improvement and the river Dommel in the south of the Netherlands where restoration focused on remeandering.

For further information: 

Piet Verdonschot