The Turkish bridge over the old outlet
The coastal plain of Paleros
The coastal plain of Paleros
"In the fifth millennium B.C., the Palairos lagoon turned into a freshwater lake. When ancient Palairos was founded in the 6th century B.C., shallow lakes and swamps dominated the southern and central parts of the plain. At that time, a narrow canal-like connection between the Bay of Palairos-Pogonia and the Lake Voulkaria existed and was possibly used as a slipway for ships.
Lake Voulkaria was connected with the Ionean sea in the south during Odysseus' days. This led to the following conclusion in the paper:
So, Plagia was practicly an island. We just found an island east of Ithaca (Lefkas). Question is, which island could Plagia have been? It could not have been Doulichion, it is even smaller than any of Odysseus islands Kefalonia (Samos), Zakynthos (Zacynthos), Lefkada (Ithaca). Nevertheless, it could have been one of Odysseus islands itself, Aigilips and Crocyleia have yet to be identified.
The paleogeographical situation for the time slice 500 cal B.C. implies that the Palairos plain served as a barricade and was important in terms of its strategic location and infrastructure. The only way to cross the lowlands was via the beach ridge between (modern) Palairos and Pogonia. The wetlands were a natural border between two landscapes: the Plaghia peninsula in the west and the foothills of the Akarnanian Mountains in the east.
This slipway can not be used by Cleopatra to escape defeat, it must have been somewhere else.
"During the following centuries, the shallow coastal lake between Palairos and Pogonia became concentrated in a smaller area. However, it existed at least until Turkish times. This is indicated by a Turkish bridge from the 17th century, which spans the outlet of the coastal lake toward the sea."
Fortunately there is more to discover about the coastal plain south at the isthmus in the paper:
Holocene Paleogeographies of the Palairos Coastal Plain and Their Geoarchaeological Implications. Vött et al