Have app 20 ft of custom Corian countertop,  two sections of base cabinets are water damaged from a leak, contractor wants to replace the countertop as he says that it cannot be removed, I have a hard time with that, has anyone encountered this and is it possible to support and remove the base units, without a new 10K countertop?

John, Linda is correct. I too have had them removed and reset by a certified Corian installer. It can be done, so don't allow that contractor to walk out with the cabinets, charge you with a new top, then resell the old top. As you well know, Corian material is very durable and has a lifetime warranty. Someone had to install it, so as Linda suggests, try to find the original installer.

If a man put it on a man can repair it. No exceptions- sometime cost considerations over rule.

Water damage to Corian? That's a laugh.

Almost all Corian counter top I've seen, the sink basins are also formed out of the Corian.  Tends to get pretty wet in there.