Traditional monitoring uses methods that need a long period of observation before the contractor and owner can judge with statistical certainty whether an impact will result in a lasting change or whether it is an occasionally occurring natural variation that disappears after a while.
With the development of real-time monitoring techniques and fast data processing systems, this has changed radically. Modern techniques allow a much quicker evaluation of impacts. This rapid evaluation allows the contractor to adjust the dredging operations directly when observed effects vary from predictions.
This is called “feedback or adaptive monitoring”. It evaluates selected variables that show quantifiable changes as a result of impacts from the construction work over short periods of time.
Computer models make it possible to assess early on whether intervention is necessary. Because possible exceedance of environmental criteria can be forecast so quickly, dredging plans can be altered immediately and environmental damage can more easily be avoided and/or limited, which also helps avoid costly downtime.
When to use feedback monitoring
This is the most comprehensive type of surveillance monitoring, but it can be costly. Consequently feedback monitoring is primarily used at projects with very strict environmental criteria, in highly sensitive environments where an extra level of caution and care is required or where legally binding limits for impacts must be observed.