Oxygen depletion occurs in a large part of the lagoon, but has been reduced since 2002 by creating larger openings around Aitoliko island and dredging channels in Messolongi Lagoon.
Oxygen deficiency prevails in a substantial area of the lagoon, but has been mitigated to some extent since 2002 by enlarging openings around Aitoliko island and excavating channels in Messolongi Lagoon.