Protect the Marshes: Line them with clay & coat them in wax!

At a recent ministry meeting a representative of a Baghdad ministry (who shall remain nameless to protect their honor) came up with a novel approach on how to protect the marshes from drying out. In all seriousness he proposed to coat the bottom of the marshes with clay and cover the surface of the marshes with a thin layer of wax to stop their evaporation.

This individual is proported to have said, "If you like the idea, I can do some research and draw up a fuller proposal."

Forgetting the fact that such a proposal would kill all the biota of the marshes (something this individual, a chemical engineer, apparently had failed to consider) one wonders who would consider such an action as being even remotely feasible?