this is adapted from a pers. msg i sent to katie rose in response to one of her posts. she suggested i post it.
i live on four acres in rural north florida which i bought in 1984 (i've been "getting prepared" for quite a while). i'd like to suggest a possibility many people may not have considered about water supply.
WHAT HAPPENS IF THE ELECTRIC GRID GOES DOWN AND STAYS DOWN?
(permanently or for just a few months? years?)
there are several ways to cope with this:
a)windmill to pump water from well.
b)solar electric to pump water from well.
d)dip water from a creek.
none of these will provide the large amounts of water on an instant's demand we are presently blessed with, but some water is waaaay ahead of no water.
i have chosen c) rainwater harvesting. this may not be suitable for all cases, but it is the best i can come up with. here in north florida we have ample rain cycled throughout the year(most of the time), and i have quite a bit of roof area. for those without these two conditions, this solution may be less attractive. a third advantage i have is that i spent years in construction work, and have a welder (and access to a nearby scrap metal yard.)
the system i am constructing (completion date - est. spring, '12) has three main features.
a) gathering - roof, roof gutters, with associated screening and piping.
b) storage - cistern, a series of plastic tanks under the house (traditional southern style houses are built up off the ground on "piers") - present capacity 2350 gallons. more capacity to be added as i go along. (as cheap tankage appears on craigslist)
c) pressure- a 25 foot tower beside the house (here's where it's nice to know how to weld) with a 500 gallon plastic tank on top, a solar powered pump that pushes about a gallon and a half a minute (while the sun is up) from the cistern, through a filter and into the tower tank. overflow drains back to cistern.
when this system is complete, i will still have and use my present water supply (100 foot deep semi artesian well with 1 horse submersible pump and 350 gal. pressure tank) which supplies excellent water (floridan aquifer).
.......but when the grid goes down - permanently or just from power outages following storms, i'll have my rainwater for a backup. admittedly, the pressure will only be about 10 to 12 psi (even less upstairs), and i won't have enough volume to irrigate other than with a drip system, but i'll have water.
all the best,