Putting a value to saltmarsh • Economic decision making

All options for saltmarsh management will have financial implications and these will be different depending on the technique adopted. Remedial techniques (i.e. silt recharge), for example, may be cheaper than hard engineering schemes, but are likely to require regular maintenance in order to be effective. All proposals must be economically sound when the total scheme life is considered and this should include the long term financial investment required to establish the saltmarsh to the point where it is self-sustaining (if this is achievable).

As stated above, the applicability of the technique to each situation must always be considered. In particular, the prevailing physical processes, as well as the key characteristics of the ecosystem, should be understood before a scheme is selected. It is possible that the cheapest scheme, implemented in inappropriate circumstances, could eventually prove to be more costly, either through the requirement for long term maintenance or as a result of impacts experienced elsewhere.

In many cases a remedial scheme may need to be combined with some form of hard engineering, with increasing costs, particularly if the erosive processes are far advanced and an existing defence has become unstable. However, conversely, if a scheme includes hard engineering (in the case of managed realignment for example) it may be possible to reduce the capital and maintenance costs of the engineered defence. It is also important to consider the ecological benefits (as far as is possible, in financial terms) that may arise when selecting the most suitable management option.

In all cases, there will be minimum baseline data collection and monitoring requirements. Monitoring is essential to ensure the success of each scheme and provide supplementary information for future schemes. Long term data collection and monitoring, therefore, should be costed for as part of every saltmarsh management scheme. It should also be recognised that this latter aspect of the work has the potential to contribute major financial savings in the long term.