Working with Nature Project database

General information

Name of navigation or waterborne transport infrastructure project Test stretch with technical-biological bank protection along the River Rhine, km 440.6 to km 441.6, right bank
Project location (nearest town or city)The city of Worms is located opposite of the test stretch.
Key project objectivesThe banks of the River Rhine near Worms are usually protected by rip-rap revetments because of heavy hydraulic impacts from navigation and wide fluctuations in water levels. The testing of technical-biological bank protection using plants or combinations of plant materials and technical structures intends to find new types of river-bank maintenance structures that consider the ecological requirements of the German Water Act (WHG) and of the European Water Framework Directive (WFD).
Contact PersonMarc Hannig
Contact Phone+49 621 1505330
PositionProject Manager
OrganisationWaterways and Shipping Office Mannheim

Project data

Characteristics of environment
Inland waterway
No protected areas
Key project dates
Project is not in the planning phase. Date project planning started2009
Project has consents/approvals. Date approval was obtained
Project construction not yet started. Construction start date2011
Date project will be completed2016
Type of project
New construction or development
Maintenance program or initiative
OtherUse of vegetation to replace rip-rap bank protection or of combinations of vegetation and technical devices to ensure riverbank stability.
Brief description
The banks of the upper River Rhine are mostly secured by technical re-vetments that are often poor in their physical diversity and therefore lack natural riparian habitats for plants and animals in the transition zone between land and water. Since riverbank maintenance has to guarantee bank stability that ensures the safety of navigation and prevents damage to the riparian hinterland, new concepts are required which combine such safety and navigation issues with improvements of habitat and species diversity. This test stretch comprising a range of alternative technical-biological bank protection measures was established to gain practical experience with such constructions under technical as well as ecological aspects. The test stretch is divided into nine test fields. In four test fields, the rip-rap was removed above the AZW water level (~ 20 cm below the mean water level) and was replaced by new technical-biological protection e.g. willow brush mattresses, reed gabions, pre-cultivated vegetation mats on different filter mats. Along another four test fields, the rip-rap was left in place to protect the bank, but was ecologically improved with plants or other structural elements e.g. willow branch cuttings, living fascines, (dead) wood fas-cines, a shallow-water zone behind a stone wall. In one test field, the bank was left nearly without any protective struc-tures to be exposed to erosion. The results of the test that will be recorded during a 5-year technical and biological monitoring scheme can help to improve the physical-structural diversity of the river banks and are expected to improve the acceptance of waterway-maintenance works among the local residents (better recreation facilities, nature conservation…). So the results found at this test stretch will also be important for the future management practices on other German waterways, considering the ecological demands of WHG and European WFD.
Indicative size
0.5 to 10 million US$

Working with Nature philosophy

Were steps taken to understand the environment before any work was started on the development of the design of the project?
Before the planning began, the best location of this test stretch had to be selected under consideration of the following aspects: outside of nature conservation areas, the rip-rap should be covered only by few plants of low ecological significance. Then the vegetation was surveyed and mapped exactly as basis for the planning and as reference for the future monitoring. The faunistic monitoring covered aquatic (fish, macrozoobenthos) as well as terrestrial animals (e. g. reptiles, birds).
Were stakeholders or potential partners involved from the very beginning in the initial process of identifying potential options or solutions and agreeing on a preferred option (i.e. instead of being consulted on already defined options)?
Stakeholders in nature conservation and water-policy authorities, mu-nicipalities and local residents were informed at the beginning of the project and during the planning. Proposals made by them have been considered along with those of two consulting engineers that made the further detailed planning. For technical and ecological consulting the German Federal Waterways Engineering and Research Institute and the German Federal Institute of Hydrology have been involved too.
Was a solution identified which provided a clear ‘win-win’?
A win-win situation is expected both for the local Waterways and Shipping Office (e.g. better public acceptance of future maintenance works), for nature conservation and maintenance of waters by providing new habitats (European WFD), more attractive recreation sites (for the local residents), preservation of the characteristic river-landscape.
Was the project designed to work with and make use of natural processes (e.g. ‘letting nature do the work’)?
Did the project include benefits for nature or other environmental enhancements beyond what was legally required?
WHG demands the preservation of ecological functions of waters and - also on the Federal waterways - the improvement of the riparian structural diversity. The project provides the basis for types of bank pro-tection that have a more ecological orientation. Thus, a range of different applications for future waterway maintenance projects become available that are adapted to the local conditions. This will lead to more ecological diversity of river banks beyond the degree that is legally demanded.
Did the project follow, in order, the steps described in the Working with Nature Position Paper?
1. Project objectives had been set: Replace rip-rap revetment above AZW (see before) by different types of technical-biological bank protection measures. 2. Understand environment: regard the local ecological vegetation of low value, no nature protected area); the situation for ecological im-provement is given. 3. Stakeholders had been involved / adviced in a first planning concept. 4. After that two consulting engineers made a detailed construction planning.
Reasons/motivation for taking this approach
The banks of the River Rhine near Worms are usually protected by rip-rap revetments because of heavy hydraulic loads from navigation and wide fluctuations in water levels. The German Water Act and the European WFD demand more consideration of ecological aspects in the management of waters. The location of the test stretch was chosen because of the low ecological value of the original banks and the heavy hydraulic impacts there. Technical-biological measures that can guarantee the bank stability under these extreme conditions will also be able to protect the banks on other sections of the River Rhine or other waterways under similar or less ex-treme conditions and can be most helpful in considering bank stability, ecological effectiveness, and future maintenance requirements. This also will lead to better acceptance of waterway maintenance works by the different stakeholders, and the approval of measures will be achieved faster and in a more effective way in the future.
Cost implications
Costs were lower than the conventional approach to this type of project (i.e. cost savings were made)The costs of biological-technical measures cannot be simply compared with those of the construction of rip-rap revetments. At the moment, no information is available about the costs of creating new rip-rap on this part of the Upper Rhine. Costs for the maintenance of the technical-biological measures are not yet known, they will be calculated in the next coming years.
No additional funds were provided from third parties
No extra costs compared to conventional approachExtra costs were incurred by the higher percentage of planning costs for the new technical-biological measures. Moreover, the intensive long-term monitoring of this new bank-protection measures will generate additional costs in comparison with rip-rap revetments.
Costs were marginally or significantly higher than a conventional approach to this type of projectThe costs for bank protection in the test stretch will be higher, because this project is the first testing of several new measures along river banks exposed to intensive ship traffic and therefore hydraulic loads as well as wide fluctuations in water levels. Moreover, all the benefits have to be taken into account that will be gained elsewhere in the future in similar projects besides the improved habitat and species diversity and additional recreation options.
Percentage of the total cost that was an additional cost associated with adopting these elements of Working with NatureAdditional costs are incurred especially for the first planning of these new measures (costs for planning are about 10 % of the implementation costs), the very intensive surveys before and during project implem
Did existing legislation help or hinder your application of the Working with Nature philosophy?
The approach adopted did not help to meet legal obligations
What was done did not exceed legal requirements
No problems were experienced with existing legislation
The approach was not taken despite legal requirements
Legal requirements did not prevent the Working with Nature philosophy being applied
Other implicationsManagement plans (WFD) for this part of the River Rhine comprise only general proposals for improving the riparian structural diversity. Within the test stretch this demand is met not only by one option (e.g. planting willow-branch cuttings in the rip-rap revetment) but by different types that may become routine practice in the future maintenance of riverbanks. Moreover, these practical experiences may be beneficial elsewhere and will support the implementation of the WFD.
Further information
See common Internet-portal of BAW and BfG 2 reports of 05/2010 and 01/2012 (in German)