Google Maps API - overlay a polygon at a certain height with opacity (to display flooded areas)

Using the Google Maps API, I’m trying to understand how to draw a polygon above a Google map with a certain height, using opacity so that any ground mass that is below the height of the polygon is displayed as highlighted, and that is, the ground above it will not appear as selected (I I hope I can use a polygon with an opacity of 40% to do this.)

So, for example, if I draw a polygon at a height of 100 m above the ground, which ranges from, say, from 95 to 105 m, all the earth in the polygon, which is less than 100 m, should be highlighted, and everything above should not be .

This will allow our underwriters to see at different flood levels above the water source whether one or more objects covered by insurance will be flooded.

This can be done very easily in Google Earth and in the GE API, but unfortunately, we are deploying this application for thin clients through the Citrix client, which does not allow us to install or use the Google Earth plugin ... talking about creating life is hard !! : - (

I searched this many times many times and many times and did not find anything - to a large extent I start to think that this is impossible to do - I really hope that someone can help me and prove that I am wrong!