Several lessons were learned concerning physical parameters and the technical realisation:

  1. Determine physical parameters in close cooperation between physicists, morphologists and (marine) ecologists to determine effectiveness, and with contractors to determine workability (realistic / pragmatic approach).
  2. Use expert knowledge and numerical models to predict the behaviour of the bedforms in the sand extraction site to make sure that they are relatively stable and allow sufficient time for the ecosystems to develop.
  3. The size of the sand extraction site determines the type and number of ecosystem-based bedforms that can be situated in the site. Appropriate modelling techniques can identify any side effects of the landscaped bedforms (e.g. large flow contraction or sedimentation-erosion patterns).
  4. Make sure that there is enough space around the bedforms to manoeuvre the dredging equipment. Too little space directly influences the extra costs of creating bedforms.
  5. It is advisable to check whether the existing seabed composition (spatial distribution of grain sizes after dredging) already provides sufficient gradients. If so, bedform creation may not be necessary.
  6. Small bedforms are more difficult to create, as the dredging ships need to manoeuvre more. This will result in a loss of productivity and increase in costs.
  7. Bedforms that have an orientation more than 20-30 degrees off the main current direction are much more difficult to create, so these are also more expensive.