I'm not sure what you're trying to accomplish with silica gel. If you're trying to absorb significant quantities of water while the car is in use, I would use (and have used) towels.

If you are trying to just dry things out in betweeen dousings, I would start with a wet-dry shop vac.

As I understand things, silica gel is "single use", once it integrates moisture into its chemical structure you chuck it.

Short of finding and fixing the leak, seems to me what you need, is to suck first then blow (sorry I just had to go for the bad joke). Seriously, when you have moisture absorbed in carpet, first you remove as much as you can with towels and vacuum, then you try to evaporate the remaining moisture. Creating airflow (preferable warm, dry airflow) is what's required for evaporation. Hair dryers and heat guns come to mind.

Also, many shop vacs both suck and blow, and might require less constant attention, and might not burn out quite as quickly as say some cheap ass hair dryer from China.

super unconventional... puppy pads ... or those "adult" depend-type pads... put the absorbent side down sit on the plastic... put a towel over that for comfort...i would go with the above shop vac advice first. is there any way of addressing the underlying leak first?k

How about using a shallow cooking pan. Empty it if it gets too full.
If it will line up with the leak without running over it when the car drives in, you're done.

Try lifting the carpet; check and see if the floorboards aren't rust-holed through - the leak could be from underneath.

Well there is good news here, of sorts. This is a common problem on those cars. And that problem is.........there is a drain tube running from the side outer cowl ( under the removable grid wher the wind shield wipers are attached ) that is supposed to let the water run down to the ground. Some times the tube got ran into the passenger compartment, or kinked, or latter just broke, allowing the water inside.
You can access the hole from the out side ( it's in the low spot of the cowl) and run a stiff wire or coat hanger into the hole , and see where it comes out. You can put a new peice of plastic tubeing on to repair.
Also look at the seams on the pieces that makeup the cowl, they are coated with cauking, so if it's bad put some Silacone calk on them.
But I would first check the top and side of the windshield for leaks, by pouring water over just that aeria.
I belive ther is also a large drain hole in the floor board. Look under ther car for a large flat rubber plug, that you can pull out to help in drying and drainage.
As to the Silica, you can reuse the stuff at lowes. put it in some socks, white so you can see the color change, because it turns pink when it becomes satureated. Warm air / sunshine will dry the Silicone and return it to white. Silica only soaks moisture, NOT water. Youv'e got to get the water out first, ( wet-vac)

Check the garden section for "soil moist" It's a gel thingee that you can bury in your garden to hold liquid. It can go through a lot of wet/dry cycles before it breaks down. Fix the leak first though, as it's only going to happen again if you don't.

Thanks for all the great feedback.

Richard...shop vac is a good idea...so obvious, I didn't think of it. ; )

Kimberley...another good idea...if I opened them up, they would be a lot less messy than the newspaper...which is now a grey crust on the drying carpet.

Edward...the cooking pan would be a good idea if it were an actual drip...unfortunately It seems to be more of a hidden oozing.

Briggi...there are no holes in the floorboards...yet. I don't use the car during the week, since I take the bus, so the water that accumulates isn't coming up through holes. After a few days of particularly heavy rains recently, there was almost an inch in the car.

Dan...I'll look tonight to see if I can find the drainage holes and check the caulking.

Cliff...I wish I knew where it was coming in...would make it a lot easier to fix. I've gone in the car when it's raining and checked around the windshield...dry and tight as a drum. I've felt along the floor up near the gas and break pedals and all the way around. It's damp, but I can't figure if it's a wicking thing or where water is actually coming in.

Bad Dawg...Good suggestion with the "soil moist"...sounds most like what I've been looking for.

Thanks for all the help.

WW