Case study:Restoration of the Erft-river in Weilerswist

This case study is pending approval by a RiverWiki administrator.

Approve case study

 

4.00

(one vote)

To discuss or comment on this case study, please use the discussion page.

Location: none specified

Edit location

Project overview

Edit project overview

Status	Complete
Project web site
Themes	Economic aspects, Fisheries, Flood risk management, Habitat and biodiversity, Hydromorphology, Monitoring, Spatial planning, Water quality
Country	Germany
Main contact forename	Volker
Main contact surname	Gimmler
Main contact user ID
Contact organisation	Erftverband
Contact organisation web site	http://www.erftverband.de/
Partner organisations
Parent multi-site project
This is a parent project encompassing the following projects	No

Before (left) and after (right) restoration

Project summary

Edit project overview to modify the project summary.

The Erft River was heavily trained in the 1960s to provide a higher discharge capacity for flood prevention and to make it easier to mechanically maintain the river. High dams were built along the river banks and the river bed was secured with large rocks. This river training resulted in a river with few structures ans a low morphological diversity. The restoration project has been implemented in Cooperation of the Landesbetrieb Straßen NRW (the state road authority) and the Erftverband (water board in the Erft watershed) to compensate the impact on nature and environment caused by the construction of a new road. The measure has been necessary to reach the Good Ecological State of the Erft required by the WFD. By adressing the need for compensation with a river improvement measure, inefficiencies in public spending has been avoided. The project started in April 1995 and aimed at developing a structure-rich, ecologically permeable stretch of the river with regularly flooded meadows and a high potential for self-development. About 10 hectares of cropland were bought and turned into a meadow on the left hand side of the river, towards the lowest part of the valley. The dam along the Erft separating this meadow from the river has been removed. The rocks securing the river bed on that side have been removed and groynes have been built in the river bed to add morphological diversity and initiate lateral erosion. The groynes have been designed in cooperation with the local fishery association, and according to their observation, young fish which have been drifted away by floods in the past are now able to stay in the area.

Monitoring surveys and results

This case study hasn’t got any Monitoring survey and results, you can add some by editing the project overview.

Lessons learnt

This case study hasn’t got any lessons learnt, you can add some by editing the project overview.

Catchment and subcatchment

Select a catchment/subcatchment

Site

Edit site

Name
WFD water body codes
WFD (national) typology
WFD water body name
Pre-project morphology
Reference morphology
Desired post project morphology
Heavily modified water body
National/international site designation
Local/regional site designations
Protected species present
Invasive species present
Species of interest
Dominant hydrology
Dominant substrate
River corridor land use
Average bankfull channel width category
Average bankfull channel width (m)
Average bankfull channel depth category
Average bankfull channel depth (m)
Mean discharge category
Mean annual discharge (m3/s)
Average channel gradient category
Average channel gradient
Average unit stream power (W/m2)

Project background

Edit project background

Reach length directly affected (m)	100100 m <br />0.1 km <br />10,000 cm <br />
Project started	2002/04/01
Works started
Works completed
Project completed	2009/12/31
Total cost category	500 - 1000 k€
Total cost (k€)	717000717,000 k€ <br />717,000,000 € <br />
Benefit to cost ratio
Funding sources	Landesbetrieb Straßen NRW (the state road authority) and the Erftverband (water board in the Erft watershed)

Cost for project phases

Phase	cost category	cost exact (k€)	Lead organisation	Contact forename	Contact surname
Investigation and design
Stakeholder engagement and communication
Works and works supervision
Post-project management and maintenance
Monitoring

Reasons for river restoration

Edit reasons for restoration

Mitigation of a pressure	Flood risk management
Hydromorphology	Quantity & dynamics of flow, Continuity for organisms, Continuity of sediment transport
Biology	Macrophytes, Macrozoobenthos
Physico-chemical
Other reasons for the project

Measures

Edit Measures

Structural measures
Bank/bed modifications
Floodplain / River corridor
Planform / Channel pattern
Other
Non-structural measures
Management interventions
Social measures (incl. engagement)
Other

Monitoring

Hydromorphological quality elements

Edit Hydromorphological
quality elements

Element	When monitored		Type of monitoring		Control site used	Result
	Before measures	After measures	Qualitative	Quantitative

Biological quality elements

Edit biological
quality elements

Element	When monitored		Type of monitoring		Control site used	Result
	Before measures	After measures	Qualitative	Quantitative
Macrophytes	No	Yes	No	Yes	No
Invertebrates	No	Yes	No	Yes	No
Angiosperms	No	Yes	No	Yes	No

Physico-chemical quality elements

Edit Physico-chemical
quality elements

Element	When monitored		Type of monitoring		Control site used	Result
	Before measures	After measures	Qualitative	Quantitative

Any other monitoring, e.g. social, economic

Edit Other responses

Element	When monitored		Type of monitoring		Control site used	Result
	Before measures	After measures	Qualitative	Quantitative

Monitoring documents

Upload monitoring documents

Image gallery

Edit Image gallery

Additional documents and videos

Upload additional documents

Additional links and references

Edit links and references

Link	Description

Supplementary Information

Edit Supplementary Information