Eranti Engineering Oy
Harjuviita 6 A
02110 Espoo
Finland
Tel. +358 9 455 7500
esa.eranti (at) erantiengineering.inet.fi

Ecoimpact

Annual environmental impacts that result from activities of a company, a public organization or a household, for example, can be estimated in equivalent square kilometres. This is easy because the impacts are often almost linear. Cumulative effects can be simplified. For example, the impact of carbon dioxide emissions can be estimated as a portion of the basic emission scenario described in the ecoscale page.

Example: The environmental impacts of various activities in the harbour area of a South-Western Finnish port have been estimated as follows:

Port activities

Carbon dioxide emissions from energy usage -3,6 km² eq.
Harbor fields and channel areas, footprint effect -2,0 km² eq.
Dredging and dumping activities -0,1 km² eq.
   
Common effects of sea traffic and port activities  
   
Water service and management waste water from ships -0,2 km² eq.
Garbage service for ships -0,1 km² eq.
   
Environmental impacts of navigation in the harbour area  
   
Carbon dioxide emissions -18,0 km² eq.
Nitrogen oxide and sulphur dioxide emissions -1,0 km² eq.
Tributyltin emissions (from foreign ships, Finnish ships have epox paints) -0,1 km² eq.
Other effects (risk of accidents, erosion caused by sea traffic etc.) -1,0 km² eq.

Comparison of environmental impacts of port activities with other common activities

Port activities, environmental impacts (1500 employees) -0,004 km² eq. / employee
Finland's agriculture, footprint effects (50 000 employees) -0,1 km² eq. / employee
Finland's forest industry, footprint effect (50 000 employees -0,25 km² eq. / employee

The port concluded that its most efficient way to reduce environmental impacts is to improve the efficiency of service for scheduled line vessels as necessary. If these vessels can balance traffic delays by more efficient cargo handling and service in port, fuel consumption will reduce (a ship uses 50% more fuel per nautical mile if its speed rises from optimum to full speed). Carbon dioxide emissions and also nitrogen oxide and sulphur dioxide emissions are cut.

It is of interest to note dredging operations and especially harmful substances in dredged spoil have been the focus of environmental authorities. Permitting and restrictions have cost the port a lot of money and management time.

Eranti Engineering Oy pointed out that the port is not responsible for the harmful substances in the sediment. Furthermore, suspension streams connected to dredging are marginal in natures own suspension streams. The bottom is cleaned both at the dredging site and at the dumping site as shown in the illustration below.