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Example # 1

I presently catch from a 2100 sq.ft. enameled steel roof, pipe into 4 black
polyethylene, above-ground tanks, 1600 gal. ea., with 2 additional in
reserve.  It's not enough tankage for our 8 to 10 inch annual rainfall.  The
2 reserve tanks will be connected to the house roof when it is built.

Catch figure is 0.6234 gal/sq.ft./in., by my calculations.  Experience with my 
system bears this figure out.  

When I find a reasonable-costing storage of 5,000 to 10,000 for my excess
water (maybe an old above-ground swimming pool with cover), I can keep all
my roof collects.  The excess will be for garden use and (hopefully not)
fire fighting.

A designer up in Taos recommends a tank inlet filter of polyester floss
batting (available in hobby stores for pillow stuffing) in something like a
large kitchen collendar, between the gutter and tank inlet.  I've not yet
done that, get a thin layer of sediment in the tank bottoms from roof dust.
Slight murk in the water for a day or 2 after a rain, quickly settles out.

Drinking water goes through a ceramic microporous filter.  I add a small
amount of colloidal silver to the incoming water (2 chamber, gravity
trickle-down filter, resembles a coffee urn) to supress bacteria in the
filter elements.  Must be effective, never get the runs from drinking it.
Tastes much better than the local well water, which runs a bit salty for my
taste, is getting worse with time.

My water use is frugal, 670 gal. since New Years, that's just shy of 7.5
gal/day, 223 gal/month, per person.  The Taos designer budgets 10 gal/day.
This requires that we do not use flush toilets, rather composting our

I have plenty of water to use, none to waste.

I follow Joe Jenkins' _The Humanure Handbook_, and it works well.  I have
the best, most efficient garden in the area.  Fertilized by my own
composted manure and garbage, irrigated with my roof water.

And there is plenty of water left over to carry me to the next rainy
season (mid- to late-summer).

Soon, I will add a Staber horizontal-drum automatic washing machine, 18 gal.
a load, soft-start motor, designed to operate on solar power systems with
minimal consumption.  And be serviced by the owner.

5 miles west of Mountainair (real close to the middle of New Mexico)

Example # 2

Since the small, 82 gallon tank worked so well, I have now upgrated to a larger, 500 gallon tank. Using the same 10 foot section of roof gutter, the tank remains nearly full most of the time
It was sometime in March the following year, (2001), that I was thinking about the coming summer... I knew that there might be a drought again, Summer months were a bit dry around here in Texas, so rainwater might be scarce, and, an 80 gallon tank would not be sufficient during a drought.

I needed a water solution that would tide me over extended dry spells. It occured to me, that I should use a bigger tank.

I remember that day, I was in the back yard, leaning up against my old silver butane tank (which I used in the Oil Embargo days of the 70's for solar heated hot water) and wondered where I was going to get a larger tank.... I hated to spend the money for a large water tank. I went into the house and looked out the window at the tank I was just leaning against, and it dawned on me that I could use 'that' tank... I'm glad it wasn't a snake or it would have bit me. Now the old, 500 gallon, silver tank is painted flat black, it looks sharp, and it's a proud addition to my backyard water catchment system.


Example # 3

1500 gallon cistern In January 1996 we installed a rainwater catchment system to capture Oregon's abundant rainfall. Portland receives between 3 and 4 feet of rainfall annually. During a gentle rain a typical Oregon downspout sheds several gallons per minute. Our twelve hundred square foot roof captures on average 3600 cubic feet (27,000 gallons) of water per year.

In 1998 we received approval from the city of Portland to use this water for all household use. This system, which cost less than $1,500, consists of the following components:

Example # 4

Environmental Concerns
Although it may go without saying, at Dancing Rabbit we're always looking for ways to be more sustainable and self sufficient. One of the ways we've determined we can do this is by developing rainwater catchment systems. The water from these systems, if managed correctly, can be used for drinking, bathing and cooking as well as for garden irrigation. As with a lot of what we're doing, this causes a lot of dilemmas and often necessitates compromise. Rainwater catchment is no exception, especially when it comes to the storage tank itself. What should it be made of? Redwood is a proven building material for water tanks but is a diminishing resource and not local to our bioregion. Plastic? This of course is a petroleum product and carries with it certain health concerns when used for storing drinking water. Fiberglass? Pretty gnarly manufacturing processes. Metal? Concrete? Ferro-cement? The options are many and none of them seem to totally satisfy concerns for sustainability and environmental impact. Another issue to think about is tank location. Above ground? Below ground? With no solution that really appealed to our ecological sensibilities, my wife, Alline Anderson and I elected to go with an underground, reinforced concrete cistern that was integrated with our cottage's foundation serving as a portion of the north and west sides. One disadvantage of Portland cement is the huge amount of energy required in manufacture and another the CO2 emitted as the concrete cures. Advantages include the durability and added thermal mass, plus the fact that two walls of the cistern perform double duty as a portion of our cottage's foundation.


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