Although historically the primary objective was to optimise dredging operations and economic benefits with little regard to the environment, today in most cases dredging projects are evaluated and managed to minimise adverse environmental effects, whilst still maximising economic and environmental benefits. There are existing procedures and regulations in place which are generally considered to effectively avoid and minimise the potential for maintenance dredging and disposal operations to cause environmental harm, particularly the requirements of the FEPA licensing process. In addition, in recent years dredging has become a more scientific process with greater emphasis being placed on continuous survey of the channels to minimise dredged volumes. Changes in dredging practice and port operations have greatly reduced the amounts of material dredged over the past decade. Improved dredging technology and position fixing equipment allows more precision which has resulted in real reductions in the amounts of materials dredged and deposited (Murray 1994a).

In most cases, existing regulations and careful dredging practice are sufficient to avoid the potential effects discussed above and there is no need for further steps to be taken. Where adverse effects are identified or a precautionary approach is considered necessary the following actions may be taken to avoid or minimise impacts, many of which are already in operation as part of careful dredging practice:

• managing and informing contractors,
• timing of dredging and disposal operations,
• selection of BATNEEC dredging methods,
• reducing amounts of maintenance dredging,
• promotion of beneficial use,
• selection of BPEO disposal sites, and
• monitoring and record keeping.

Managing and informing contractors

Timing

Selection of dredging methods

Reducing the amount of dredged material

Beneficial use

Selection of disposal options

Monitoring and record keeping

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