mtviolet:

Babs, I also do what  Grame said, I always fill the canner and sometimes it is with a jar of water, i use saved "used" lids, if they don't seal, no loss.  figure I have to store the jars anyway, might as well have them full of water in case I need it.  Also, when i re-use the lids they seal just fine.  So far this year I have had one not seal out of 20+. 

I am not loosing anything if the lid doesn't seal, and I am gaining some water storage if it does.  I have been doing this about 5 years now.  when it is time to can food in the jars, I just open and dump the water onto the garden.  really helps in the jar washing department too.  no surprise spiders have taken up residence, or dust in the jars.  so much easier to wash them and can.  to me this is a no-brainer. 

for me it is just an easy way to make use of expensive lids, and space. 

Oh, MAN! Why haven't I done this before?! It seems like such an obvious way to do things, and I love the reusing lids idea too.

I store water in 2 liter soda bottles, & have had it keep well for 6 months to 1 year.  We "rotate" the water when drought conditions do not allow watering of the garden in July or August, & guess where we dump the "old" water??

I think storing some "canned" water is a good idea, because you never know when some sterilized water will come in handy.  Using bottles to "fill" the empty spots in the canner seems like an intelligent way to do it to me, especially with re-used lids.

 HI z. yes its agood idea to use cannedwater just I never atempt it but I use the tap water put a drop or a water sterlizor in it and shut it off for 6 months myself never canned it just soda bottles we have here at the house I wash it dry it good and use them instead and a rain berral and 2 big water jug things they work out fine just don't for get to date them and use them in 6 months.

 I think I will try it also.  I have summer squash that is ready to can.