Rain gutter-fed actually. Here's my set-up, making "lemonade" out of a city building code requiring any new construction/remodeling project (a garage/studio space) to incorporate a "rainwater reclamation system".

This is 300 gallons worth of "lemonade".







Oh, and tomatoes don't belong on sandwiches. There, I've done it. I always wanted to hijack my own thread.

Looks like a neat system. My only question is about freezing. I don't know where you are located, but in our area (Maryland) that white drain pipe would be sure to freeze and burst the first winter, and depending on the winter, maybe even the stored water.

I can really see it be a handy resource though.

The lowest temperature ever recorded here was 44 degrees F.

Looks like a fine and functional, if not overtly beautiful system to me.

At some later date you might upgrade to a simple first-flow dump and strainer system to limit how much dust and detritus gets into the tank. It keeps the water a good bit sweeter and reduces the need for tank cleaning.

First-flow dumps can be mechanical tilt mechanism , or even a float valve but IMO the best ones are simply a small, a gallon or so per hundred square feet roof area, of dead storage that get filled before the water overflows to the main storage. When the rain stops this small tank drains by way of a small hole so it is automatically ready for the next cycle. No moving parts is good for reliability.

The strainer is ideally set up to be self-cleaning and, because the first flow depends on a small drain hole, is best placed before the first-flow unit.

Sounds complicated I know but these units can shift a rainwater collection system from being primarily landscape watering and toilet flushing, drinking if you're in dire straits, certainly useful enough to justify the system, to a supply of water you can drink and still maintain a smile.

I think its a grand idea to have every house equipped with a rainwater collection system. It is smart to conserve what we have and, if and when the municipal water fails for a few days, everyone has a reserve.

For areas where freezing is an issue the cistern/s can be placed below the freeze line and the plumbing can all be set up to drain so there is no trapped water to freeze.

Art, do you have any good links to those dumps? Most places I've looked seem to skip over them. I did find one good one, but lost it when my last computer died.

Sue

That is a Nice system you have there,Let's hope the air traffic stays clear of your place,Jets often times,Vent the tanks when landing or on approach.

I don't see a provision for overflow. I calculated that my 50 gallon rain barrel will be filled with less than 1/4 inch of rain from the single quadrant of roof that drains into it. The rest goes into a hose coming off the side.

I use my rainwater primarily for watering my house plants. Tap water and ground water is extremely hard around here, and the lime buildup will coat the pots white as well as clog the soil and poison the plants. Since in Minnesota we do have to worry about freezing, I have a second rain barrel in the basement I drain it into for house plants in the winter. I keep a submersible aquarium filter in that one to keep the water sweet.

My provision for overflow is a new system that NASA developed as part of their REALSIMPL interplanetary human occupied travel ship (IHOTS) program. The theory is that as the level of the water rises in the tank, it reaches a point where it's total volume exceeds the volume of the container, and at that stage a physical gravitational principle kicks in and, via a built-in surface tension-fed mechanism, the excess fluid travels down the outside of the storage container (thus providing some built-in much needed self-cleaning action) until it strikes the soil surface where I have deposited a large quantity of fescue (grass) seeds thus turning the entire system into a generally redundant extremely expensive nutrient (GREEN) project which made it eligible for federal funding by an agency started by Al Gore called SPILL (Special Projects In Licensed Larceny). A side benefit of this system is that it self backflushes the debris screen in the top opening of the tank rendering the entire system practically maintenance-free.

Dear Lord: forgive me for this post.

Are you referring to these?

Rain Harvesting

Found it at North American Rain Collection Systems

(No affiliation, etc.)

I reviwed a few web sites for a good first-flow device but, as you noted, a lot of the sites don't even mention them and I got distracted before I found something I thought suitable. Sorry.

I note that the pdf link Stevenpd provided features a picture of a workable version on the first page. The 'T' at the top directs the first few gallons to a dead-end. Once that initial eight feet of dead-end pipe are full any further flow goes to the tank.

Some first-flow setups use a series of reducers to keep the first dirty water stays in the tank but the setup pictured would IMO do a pretty good job because the vertical length of pipe used as a first-flow tank is narrow enough to limit mixing.

The pdf brochure is marketing something they call "first-flush" which is a valve the control draining of what I call the first-flow tank. Different language but same idea. The first few gallons off the roof gets diverted and discarded so bird droppings and dust, anything that might dissolve in rainwater, get excluded, for the most part. Larger trash, bugs, and stuff that might float out of the first-flow tank get removed by a simple mesh filter. There is a nice filter in the pdf but I've seen a piece of fiberglass window screen inserted at an angle in a pipe.

Of course, obviously, the good people at RainHarvesting.com have engineered solutions that they will sell you. The people I've been around were more shade tree mechanics and they designed and manufactured all their stuff from plumbing fittings they buy at the hardware store.

Using a simple plumbing 'T' as a first-flow diverter, and letting its filling trigger flow to the storage tank is good shade tree engineering in my book.

A couple of interesting sources, also follow links in page:

http://www.irc.nl/page/29189#information

http://dfwnetmall.com/energy/rainwater-catchment/first-flush-diverter.htm

Suggests a first-flush setup may do little good:
http://www.harvesth2o.com/first_flush.shtml

A complicated version:
http://www.slowsandfilter.org/first_flush_diverter.html

http://www.harvesth2o.com/RainwaterHarvestingManual_3rdedition.pdf

A thesis exploring various forms of first-flush. evidently the agree upon terminology, devices. An interesting read but a bit tedious:
http://rainwaterharvesting.tamu.edu/Justin%20Mechell%20Thesis.pdf

Reading/scanning most of that I'm struck by how little hard information there is that is applicable to any system any average homeowner is likely to build. Also how much overlap there is in sources, and how much deciding on a system is going to be pretty much like it was twenty years ago when it was handymen and backyard tinkers assembling systems based on their own intuition and estimations.

Yes there are some guidelines and lots of good ideas and things to think about.

I suspect that the safest course would be to use collected water for drinking only after it is chemically treated. I might give it some basic testing. Or simply make coffee or tea out of it so there would be far less chance of microbes being an issue.

Hilarious! But I guess you don't really need to direct the overflow away from the foundation like we do here in the North. We have basements, and one of the main reasons to have gutters is to direct the rainwater away from the house, so it won't flow into the basement. You probably don't have a basement, so it's not a big deal.

Thank you both for the links, I'll have to go through them.

One thing I have noticed about discussions on rainwater harvesting is that people are worried (possibly excessively) about contamination, automatically comparing it to what they think comes from their tap. They don't seem to realize that most municipal water supplies aren't providing pure water. Even chlorinated tap water isn't perfect, it simply reduces pathogens and contaminants to what is considered a safe level.

For instance, here are the test results for Los Angeles (2010)

It shows that there are still fecal coliform bacteria in the water. It shows that there is still Acrylamide, Epichlorohydrin, Aluminum, Arsenic, Barium, Nitrates, Radionuclides (like uranium), plus the stuff they add to disinfect the water: Trihalomethanes, Haloacetic Acids, Chlorine, Bromate.

The bottom line with rainwater harvesting is that it can be the difference between having water and not having water. If you store water, great. With rainwater harvesting you can bathe and wash clothes. If the disaster is extensive and you run out of your stored water, you've still got options.

Sue

Be sure and keep the setup hidden behind a fence. In some (many?) municipalities, you do NOT own the water rights on your property. Even to collect rainwater. I've never heard of that being enforced around here, but I know it's the law in my area.

Susan - of those links you might want to go over this one first. It is a guide from Texas and it pretty well covers all the basics and, IMHO, would serve as both introduction and overview.

http://www.harvesth2o.com/RainwaterHarvestingManual_3rdedition.pdf

GoatRider: Only a crawlspace, and even that's up towards the front of the house. Back by the tank it's just a concrete slab. I know what you mean about the basement issue, though. In the springtime, I could fish in my old basement back in Iowa.

Thanks Art! All good information. Provides a great deal of food for thought.

It does look like there is some guess work still involved in determining first-flush volume. In this case it would be the old axiom, "Better safe than sorry". Especially if you are going to consume it rather than use the water as "gray" water.

Nice looking setup sotto ... and I have a general question about this. I am looking into catching the rainwater from my own gutters for use as gray water. Is there any advantage of a system like sotto has over just an ordinary rain barrel?

addition of one of the Sawyer .1 micron filters would strain out the critters, but not virus or anything dissolved in solution, but not much does.. possibly clear glass aquarium type container or coil of clear tubing to get some UV help... might try a final activated charcoal can (aquarium supply house)for halogens....

first volume dump
biomass slow sand
UV exposure
Sawyer
charcoal

might have something...

Following this thread reminds me that in the 1930s the Coast Guard constructed the Mother of All Water Reclamation Systems, which included a flat sloping concrete apron, roughly fifty yards by twenty yards. This collected the winter rains for the use of the newly erected lighthouse and quarters on Anacapa Island.

Unfortunately, it also collected the physical residue deposited by the thriving flock of sea gulls which inhabited and bred on the island, making the water distinctly gray. Eventually the system was abandoned and potable water was (and is) shipped to the island and stored in conventional tanks.

Today the catchment basin makes a really fine helicopter landing pad.

Of course, roofs are not the only way to harvest rainfall.

Sheets of plastic clothespinned to a rope and draped at an angle into a tub or clean garbage can would provide water that didn't need cleansing.

Art, I've been looking over the Texas document, it looks very good.

Sue