A pragmatic approach to define the ecological potential of water bodies heavily modified by the presence of ports

• A methodology to classify the ecological potential of port water bodies is proposed.
• We develop procedures for the selection of indicators and the maximum ecological potential, MEP.
• The selection of indicators is based on their sensitivity to detect port hazards.
• The MEP depends on the hydromorphological conditions at each water body.

Due to the great number of ports along the European coast, defining the ecological potential of heavily modified water bodies (HMWBs) by the presence of ports is crucial in the development of river management plans. Numerous approaches have dealt with the assessment of the ecological status of natural water bodies, but there are few which specifically cover HMWBs. This contribution proposes pragmatic approaches to define the ecological potential of port areas. Besides being coherent with the hydromorphological alterations, the methodologies developed ensure the functioning of the ecosystem while recognizing that the communities and conditions found in HMWBs are highly determined by the major hazards associated to port activities. The main output is a versatile site-specific approach able to identify the best possible indicators and reference conditions (maximum ecological potential; MEP) to evaluate the ecological potential in port areas. The implementation at the port of Santander stressed the importance of considering water, sediments and biological indicators to evaluate the ecological potential, confirming sediments as the main testimony of the contaminant episodes.