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,
Sounds like a good plan. I might suggest a steel tank on your tower. The plastic tank will degrade from sunlight over a two year time frame. Maybe go ahead and use the plastic, but cover with some light sheet metal?
A small generator and 100 gal. fuel storage to power your submersible pump might be much better for those short, temporary power interruptions.
Also might look into something to add to the rainwater storage to prevent algae and crud from forming in it.
Kudos for having a plan!
farmer guy. algae and photo-degradation are a problem with clear plastic. that's why god made opaque plastic (o.d.green, black, other).
enclosing the tower eliminates the problem. also makes it look better. also adds to total roof area. also reduces frost/freezing problems. also gives a dandy place to plant a climbing rose. don juan climbs nicely. ficus hrepens is another possibility.
i have a gas generator, not a small one. a small one would not run a one horse 240v pump. starting the genset every time the pressure tank emptied would be almost as much hassle as letting it run constantly.