Read the whole thread for the answer and description of several candidates for such projects. Why should we assume the present configuration of land and sea, which has been ever-changing for billions of years, is optimal? Here is a more detailed exposition, “Seaflooding”, on the author’s Uncharted Territories Substack site.
And that takes out the Dead Sea as a candidate. The fresh water Sea of Galilee and the Jordan River are below sea level. They and the surrounding towns would be destroyed by any out of control release of sea water into the Dead Sea.
One macroengineering plan that would do far more than inland flooding to mitigate atmospheric CO2 and enhance biodiversity, is merely deploying Algasol photobioreactors on brackish ponds in the US desert SW to produce chlorella. I’ll resurrect the Mediawiki-style model if anyone is interested in taking a look at it, but thus far, I’ve not been very motivated. I have just too much evidence that no one in power and/or influence really cares a rats ass about the fact that this would feed the world a US level protein diet of high value acquaculture, rewild the rain forests and pay for reengineering all US coal fired power plants to be practically zero emission.
It is all virtue signalling while seeking more centralized power from the Sierra Club to the WEF.