Water pollution comes from ballast water, fuel oil residue and waste disposal from ship operations as well as cargo residue.
The need for upgrading and maintenance of navigation channels at port waters would lead to contaminated sludge from dredging.
There may also be a need to alter the sea floor and natural geographical feature causing disruptive impact on marine ecosystems due to dredging and civil works (Peris-Mora et al., 2005).
A case study on the port
of Valencia in Spain was conducted.