Keeping supplies in the vehicle has some ups and downs. Being able to get to it rapidly is a valid concern. There are a few situations where bailing out, ideally with your gear, would be the best option.

But there is also the fact that any gear exposed might make your car a target for theft. Survival supplies should ease your worries. Having to worry that your stuff might wander off while you sleep isn't very comforting.

Also if the stuff is in the passenger compartment some consideration has to be given to what happens to it if you make a panic stop or radical maneuver. Unless the stuff is very firmly strapped down if you slam of the brake it is going to take off to the front of the car. If you happen to be in the way your going to get hit. Having fifty pounds of tools, tins, and bottled water bounced off your skull isn't the ideal way to start an emergency.

My estimation is that there might not be a single strategy that is best in all situation. Stored in the trunk the stuff is secured out of sight and unlikely to bounce off your skull.

If and when flooding seems to be the biggest danger and bailing out a possibility I might move the packs into the passenger compartment but keep them on the floor. Strapped down if possible.

It isn't like Tennessee wasn't at least marginally aware that there had been a lot of rain and flooding might be a problem. That would be the time to move the stuff to a spot easy to get to and to work on driving as safely as possible so the stuff doesn't end up bouncing around the passenger compartment like a pinball.

From reading this thread, here's how I summarize a strategy to this type of flood disaster:

1. Listen to the government warning and don't be in the flood.

2. If you're in the flood anyway for whatever reason, have a survival plan.

3. Your carry bag and gear should be flood-appropriate. For example, a backpack is not good for swimming, and too many tools can be too heavy.

...By the way, Art, your post reads like a general argument against keeping any kind of car kit, or maybe I read that wrongly.

As an aside, a few thoughts re "packs dragging you down:"

That's not necessarily the case. When canoeing, I have turned fairly heavy backpacks into buoyancy-positive flotation devices. For example, you pack extra canteens and only fill them half full. You double-heavy-bag every item to keep water out -- but also keep air in. As a result, many old-time canoes would float even when completely swamped -- as long as the packs were tied in.

Some hard-core backpackers have adopted this philosophy for crossing rivers. Air mattresses, Therm-a-Rests, and even the classic blue foamie mattress can provide a lot of positive flotation.

So a heavy pack can in fact be turned into an asset, flotation-wise.

My $0.02.

I have, and often recommend, a car kit so I'm not against them. But, as with all things, a car kit, in my case a truck kit, has issues of its own. It can be stolen, the temperature extremes take a toll, and if its behind you and not tied down when you stop fast your kit tries to kill you. I used to carry several heavy toolboxes in a small car and one day I stopped really fast to keep from hitting a kid on a bike. Those tool boxes ended up on the dash and hood. Something of a fluke that I wasn't brained with one of them.

I had recently picked up a carpet that was being tossed out by someone and stuffed it in the hatchback behind the drivers seat. Being light and hard up against the back of the seat when I stopped it didn't do much. The toolbox that I had shifted to the right just barely missed my right shoulder and went half way through the windshield. Had it been where it usually rode my head would have been driven through the glass by the toolbox while my body was held back by the steering wheel. Would have ruined my whole day.

As it was the glass replacement is, by law, always covered so they spent $400 putting a new windshield into a $500 car and I flogged it like a rented mule for another year. It was a car so ugly that people would get out of its way for fear some of the ugly would rub off. I had a love/hate relationship with that car.

There is a difference in using a pack or any other floatation device (in front of you), even a PFD to float in a controlled condition and another when you are suddenly plunged into deep water or swiftwater. I wear a rescue PFD that provides 23 lbs of floatation, if I jump into the water; I submerge for 2-3 seconds before coming to the surface, which is no problem because I am expecting the initial shock of being submerged. Additionally in rapidly moving water and depending upon your profile (with gear), the increased surface area can act as a wing or plane forcing you down. It is a big no-no to wear a fire helmet in the swiftwater environment, since the large brim on the back with act as a wing, which when hit by moving water will force you underwater. If you look at kayaking helmets or water rescue helmets, they have little or no brim and usually have vent holes to allow water to escape from the helmet. A backpack worn on the back and hit by moving water would likely have a similar effect and force you down. I would agree that a watertight bag or backpack with trapped air held in the arms in front of you would be a useful floatation device, but if you are wearing it on your back be prepared for an unpleasant experience. I would suggest trying it out under controlled conditions, so you can see the dynamics before you trust it during an emergency.

Pete

I agree, a buoyant pack would be problematic in many ways -- especially in fast-moving water. Good advice too regarding testing and practice, since if you're tightly strapped in the pack could tend to hold you face-down in the water (yikes). I know that backpackers normally undo sternum straps and hip belts before fording mountain rivers.

The bottom line is that there is no good substitute for a PFD. But how many have one in their car?

If I lived in those areas that get flooding, I'd have a personal flotation device in my car and in my attic. I'd also have a raft in my attic.

However, where I live in California, I don't have those things because lots of other gear are more likely to be important.

I think a surpising number of people in coastal areas have PFDs in their cars, not the majority by any means, but most of my friends from home do because they/we boat so often. Have to have the life jacket for the Wednesday night it blows (we race sailboats on Wednesdays)!

The boats always have the sort of basic orange PFDs, but we usually bring our own more comfortable type.

Re raft in the attic - While I wouldn't knock someone for going this route, I'd rather just prep a boat pre flooding conditions. I couldn't afford a quality raft for the attic and I'd rather have the boat than a mediocre raft.

How would I prep the boat you might ask? It depends entirely on what sort of flooding I expect. A hurricane is the most likely cause where I live, so I'd tie several boats of various size down at elevations unlikely to flood, then post windy event, if for some reason (A medical emergency is all I can think of) I needed to go out into the flood waters, they'd be handy.

By raft in attic, I meant something basic. A surfboard would do the trick for survival purposes. Some folks in Katrina flooding would have found such a tool to be valuable. There were quite a few people sitting on their roofs. I know of some people dying in Katrina because they went to their attics, water consumed their homes, and they didn't have proper tools to break through the roof. I understand how that could happen to an elderly person or someone with limited physical abilities. A raft or surfboard in the attic seems to have a high benefit/cost ratio.

I'm w/you on an axe in the attic