Restoration planning
Constraints in identifying river rehabilitation project success
Little is known about the effectiveness of river restoration efforts despite the rapid increase in river restoration projects. Restoration outcomes are often not fully evaluated in terms of success or reasons for success or failure and this is, in part, due to weaknesses in the design and implementation stages of project planning for rehabilitation schemes. The review of concepts to measure the success of river restoration found that despite large economic investments in what has been called the “restoration economy”, many practitioners do not follow a systematic approach for planning restoration projects. As a result, many restoration efforts fail or fall short of their objectives, if objectives have been explicitly formulated. Some of the most common problems or reasons for failure include:
- Not addressing the root cause of habitat degradation
- Poor or improper project design, skipping key design steps
- Expectations not clearly defined with measurable objectives, therefore project success is difficult to evaluate through monitoring (Bernhardt et al. 2007)
- Not establishing reference condition benchmarks and success evaluation endpoints against which to measure success
- Failure to get adequate support from public and private organizations
- No or an inconsistent approach for sequencing or prioritizing projects (Roni et al. 2013)
- Inappropriate use of common restoration techniques because of lack of pre-planning (one size fits all) (Montgomery & Buffingtion 1997)
- Inadequate monitoring or appraisal of restoration projects to determine project effectiveness (Roni & Beechie 2013)
- Improper evaluation of project outcomes (real cost benefit analysis)
Figure 1. Success rate of 671 European case studies recorded from the REFORM WP1 database.
Benchmarking, Endpoints and project success
Overall, evaluating how successful restoration measures have been, as well as determining reasons for success or failure are essential if restoration measures are to meet obligations under the WFD. Setting benchmarks and end points that are linked to clearly defined project goals is considered the most appropriate approach to help measure of success (Buijse et al. 2005).
Benchmarking
Benchmarking as a tool should be feasible, practical and measureable to help guide future decision support tools. One of the first steps is to establish benchmark conditions against which to target restoration measures. Benchmarking uses representative sites otherwise known as ‘reference sites’ on a river that have the required ecological status and are relatively undisturbed; this is then used as a target for restoring other degraded sections of river within the same river or catchment. This requires:
- Assessment of catchment status and identifying restoration needs before selecting appropriate restoration actions to address those needs
- Identifying a prioritization strategy and prioritizing actions
- Developing a monitoring and evaluation programme
- Participation and fully consultation of stakeholders
