National Id
Belgium_02
Site name
Gravenvoeren
Summary
This measure is located near the village of Gravenvoeren in eastern Belgium. It was a low-cost project to retain mudstreams/erosion consequences by the building of a horizontal dyke/dams at the bottom in the valley, which will retain the water longer in the valley, so reducing runoff and sediment transport to the villages downstream. Additionally they changed crop growing from corn to grasslands to help reduce erosion.
Light or indepth?
Light
Location description
The site is located in a rural location on the Horstregrub stream, upstream of the village of Gravenvoeren. It is located in the catchment of the River Voer, which is itself a tributary of the Meuse.
NUTS Code
Prov. Limburg (BE)
RBD code
BEMaas_VL
Transboundary
1
Data provider
Heather Williams and Chris Binje, AMEC
Source(s)
Pilootprojecten Stroomgebied Voer
NWRM(s) implemented in the case study
Meadows and pastures
Basins and ponds
Longitude
5.7720445
Latitude
50.7585409
Climate zone
cool temperate moist
Mean rainfall
800
Mean rainfall unit
mm/year
Average temperature
10
Type
Case Study Info
Average slope range
5-10%
Vegetation class
Hilly grasslands
Monitoring impacts effects
0
Performance impact estimation method
Unknown
Performance impact estimation information
n/a
Application scale
Field Scale
Age
1
Performance timescale
Immediate
Design capacity description
Design capacity of the retention pond is 6.000 m3.
Constraints
There are no specific constraints to the application of this measure type, which is a simple method of runoff capture
Crop rotation
The land cover was changed from seasonal crop rotation to grasslands under an agreement between the farmer and the local community.
Design contractual arrangement
Arrangement type Responsibility Role Comments Name
Design consultation activity
Activity stage Key issues Name Comments
Design land use change
Land use change type
Design authority
Authority type Role Responsibility Name Comments
Other
Other
Province of Limburg
The Belgian province of Limburg
Other
Other
WRO
The WRO (Waterschap Roer en Overmaas) is the local water authority on the Dutch side of the border. Although not directly involved, RWO Was responsible for a different pilot project upstream on the Horstergrub, also contributing to decreasing the flood risk.
Other
Initiation of the measure
Commune of Voeren
The local community of Voeren was involved as a full partner, initiating and financing the NWRM and appointing the VMM as executional officer of the program. The community of Voeren was furthermore involved in the entering into compensation agreements with local farmers.
Regional / sub-national water authority
Implementation
VMM
VMM was appointed as the executing agent of the project, including the detailed design.
Key lessons
Low-cost measures can make a significant local improvement to runoff and sediment load problems.
Success factor(s)
Success factor type Success factor role Comments
Financing
Financing type Comments
Barrier
Barrier type Barrier role Comments
Driver
Driver type Driver role Comments
Past flooding events
main driver
Past flooding events have occurred in the village of Gravenvoeren
Financing share
Financing share type Share Comments
Policy description
In the area of the project a lot of erosion happens during heavy rainfall events. As there is no natural stream or other way of transporting rainwater away, surface runoff occurs over the area, causing mudstreams or floodings in the village downstream. Measures to prevent this from occurring were therefore needed.
Part of wider plan
1
Policy target
Target purpose
Erosion Control
Runoff control
Policy pressure
Pressure directive Relevant pressure
Policy area
Policy area type Policy area focus Name Comments
Policy impact
Impact directive Relevant impact
Policy wider plan
Wider plan type Wider plan focus Name Comments
Regional
Water
Aquadra
Aquadra had as a purpose to strive for clean water conditions across regional and national borders. Partners in the project included the Dutch and Belgians provinces of Limburg, province of Liege, regional water authorities from these 3 provinces and the German city of Aachen.
Policy requirement directive
Requirement directive Specification
Costs investment
55000
Compensations scheme information
Some compensation was agreed with the landowner to change the landuse to pasture
Information on Ecosystem improved biodiversity
The landuse upstream has been changed from crops to grassland, which allows an increase in diversity compared to the previous land use
Information on Ecosystem provisioning services
n/a
Ecosystem impact climate regulation
Not relevant for the specific application
Information on Ecosystem impact climate regulation
n/a
Information on retained water
6000 m3 total storage volume
Information on increased water storage
6000 m3 total storage volume, compared to zero previously
Ecosystem erosion control
1
Information on Ecosystem erosion control
Slows runoff, allowing sediment deposition and reducing the risk of further erosion downstream
Water quality overall improvements
Positive impact-WQ improvement
Information on Water quality overall improvements
Reduction in transfer of sediment and associated nutrients or other pollutants downstream, by allowing sediment deposition in the storage area
Information on Ecosystem erosion control impact
Not quantified
Soil quality overall soil improvements
Positive impact-SQ improvement
Information on Soil quality overall soil improvements
The Voeren area is an area with significant erosion problems, causing mudstreams in the center of the village of Gravenvoeren. As a result of this NWRM, less good quality soil will be eroded and transported downstream.