Rain-Water Harvesting

I live alone on a small town lot in Bonavista, Newfoundland. I live simply.

Bonavista folks brag about three things: “How much wind we got”, “How much rain we got”, and “How little soil we got”. This project addresses the second of these claims. See 12vDC Projects and Soil remediation for material on the other topics.

One of the two great mysteries in Bonavista is that everyone brags about “how much rain we get”, but no-one makes use of this resource. Instead every man and his dog lug empty containers into the SUV, drive out to the spring on The Elliston Road, lug filled containers back into the SUV, drive home, and lug heavy containers inside.

Me, I just reach outside my back door and swing a bucket into the house.

I grew up in the Western Australian Desert, and for seven years had a house in Gawler, north of Adelaide South Australia. Rain-water tanks were used extensively. Bonavista’s scheme water is undrinkable (the council has implemented a permanent boil-water alert), so what am I to do?

Wednesday, July 17, 2019

A foggy morn, but the sun was out by 8am; according to the wireless the day should be sunny and warm. Much to do today.

I set out two large drawers to catch rainwater while I play catch-up to build a reservoir. I spray three snails and set them out on the driveway for the birds. The snails run away but I corral them back in place. Two are gone already. Seagulls like salted snails? I like garlic-butter snails.

This morning I added two drawers from a plastic chest of drawers. While I build up my reservoir of between twenty-seven and thirty-six litres of water.

In the shed, three jugs. The one on the right is half-full and holds my “Beckers Milk Jug” funnel with the clean stone to avoid the funnel tipping when I pour water. (See those ball-in-a-basket scams at the county fair). Theory is I will always have four jugs in motion- two full, one being filled, one being used indoors.

Hooray! Four tubs of water, about fifty litres, overnight.

Friday, July 19, 2019

Now that I am using rain water on a regular basis I ponder the “Boil Water” advisories (note the plural) posted outside the Post Office. Should I be using rain water for brushing my teeth, rinsing my blepharitic eyes? I suppose that heating water in my 113? Litre heater is not at boiling point and won’t kill bacteria.

Why an advisory? Is this just the Town Council covering its legal responsibility and avoiding a solution to the problem? What to tourists from Walkerton think of a boil-water advisory?

Saturday, July 27, 2019

The high-water mark (green tape) on the corner of the shed represents Bonavista’s annual rainfall, 1,056 mm.

If I sat in the chair I would drown.

A view of my collection area, one half of a 20’x16’ shed roof.

Tuesday, July 30, 2019

I tried making a tower of water jugs. My head contains conflicting measures. One is a settlement scheme, which means one or more tanks at the same level, with water flowing from one to another, giving time for sediments to settle. Another measure is filtration (shown above) where water passes through successive filters to remove bio matter and clay particles; but not bacteria or spores.

Wednesday, July 31, 2019

My new two-roofs water catchment area. The small box on the wall is the garden hose tap. The north-west arrow points to the kitchen sink taps. The right-facing line points to the laundry taps. The horizontal lines to the doors are my measurements for the “width” of the roof.

Thursday, August 01, 2019

Monday, August 05, 2019

By eleven o’clock my trays are almost full.

Tuesday, July 16, 2019

1056mm is just over one metre. My shed is 20’x60’, say 320 sq ft roof area.

If I’ve done my sums right I could harvest ninety litres of drinking water per day from the shed roof, probably three times that from the house roof.

Sunday, August 25, 2019

I need not buy a length of eaves trough and need not clip it to the roof. If I rig up a tank inside the shed it will need an overflow system, and will freeze for four or six months. Better to stay with “outside” and lug pails, even if I have to set up my settling system in the porch. Two scissor-trestles holding a V-shaped trough lined with overlapping shopping bags tacked to the inside will do the trick. The trough can be made of one eight-foot piece of siding ripped lengthwise.

If I’ve done my sums right, I can reap a full flask on a day of rain and ignore an empty flask on a day of no rain. I build a model from scraps in the shed. Looks Good.

The mock-up of my wooden eaves troughs. The scissor-legs will be augmented with a third leg to form a stable tripod.

The mock up of my wooden eaves troughs. The gap will be nailed closed, plastic bags used as liners, strips of toweling laid in the bottom to serve as a preliminary catchment for grit and wind-blown debris. Two-inch diameter pebbles will hold the toweling, and hence the plastic liner, in place and trap larger wind-blown debris.

Some thought reveals that I want the trough to be wide as a catchment area for rain that falls from the eaves. A 120º angle would be good. That suggests that the scissor-legs are at 120º, which for the base of the height being 18 inches above ground level suggests quite a wide base. How wide? We know that the ground angle will be 30º and sin(30º)=0.5 which is opposite/hypotenuse, and opposite=18 inches, so hypotenuse=18/0.5 or 36 inches. Add in, at least, four inches to support the trough in the 120º angle, so legs at 40” each half the width of a plank, the trough pieces half the width of a plan k, and for each end, a brace of at least 30” to hold the scissor legs in place. Build the trough, tack on the plastic bags, line with towel strips weighted down with pebbles.

By lunch time I have assembled the basic kit. I still have to tack the plastic and build a drop-plat to brace the legs in the second dimension.

Well, the troughs are in place, lined, and tested with the hose raining on the roof. The forecast is for rain tomorrow.

I pull down some planks for my rain trough project. This 9” plank is badly split at one end, but even with the split it will suffice for my trough.

The other end is chipped away. No matter; it is still wide enough to support a plastic bag liner.

Voila! Two scissor-legs with two planks laid, thin ends down, in the crotch.

Here is that gap, of ragged edges, in more detail.

I split open a plastic shopping bag; these are in good supply.

The hole is not welcome here.

Try another bag; same problem.

Sigh. I slit open two never-before-used black plastic garbage bags. I can tack them along the upper (wide, the narrow edge of the planks is down) edge of each plank. I can tack the far end (the higher end) so that rain water cannot be blown out of the end.

I slit open my old office towel. I sat on this enough to wear it through. Folded up along the bottom of the trench it will filter out bits of grit, and maybe bits of clay, although I doubt it will stop all the clay.

A view of the trickle of water from the northern (down slope) end of the trough into a tray. In real life there will be a pail, or a flask with a filter/funnel.

Another view. After this shot was taken I wedged chunks of wood inside the trough to widen it to six inches. Later I shall fabricate a drop-plate with angled slots.

I realize a great advantage of my wooden trough: I can re-locate it. A better spot might be under the porch roof, where my oil drum is now. The pail would be right by my back door, and I could easily check to see if it is near-full, whereas I can’t see the pail at the foot of the garage. No-one who drives from Bonavista to lug spring water walks so few steps lugging a pail. Or seven.

Monday, September 02, 2019

The rain trough in its new position, with the collecting pail close by my back door. Why lug pails of rain water from the shed when I can have it delivered to my back door.

Sunday, September 08, 2019

The rain trough plastic lining is stripped, so I carry the trough into the shed for repairs. The pebbles and cloth were blown onto the driveway, but the trestles held up and remain in place. I collected no water; when the wind is this strong it blows the rain line away from my trough.

The “top” end of the trough. The plastic is now tacked on this underside, as well as on the exposed side.

The underside of the trough at the spout end. I have tacked the spout out of the way; it will not be used. But it can be freed if I develop a higher pail.

The second version in place. I have tucked the extra plastic under the trench for now. The theory is that having twelve inches of blowing plastic would tend to make the trickle spray over the ground, outside the pail. The concrete block inhibits the empty pail’s inclination to wander around the property at two in the morning.

Monday, September 09, 2019

Why harvest rain-water – or drive out to the spring on Elliston Road? Because town-water is heavily chlorinated (hence the boil water alerts). How can I use this to my advantage? I rinse out the milk jar in tap water, then refill it with tap-water and let it soak as long as possible. I figure that the chlorine kills off bacteria during the soaking.

Wednesday, January 22, 2020

Sunday, August 30, 2020

Cold, windy and wet all day. I stapled two rain trough walls together and unloaded the sheets trestle.

Monday, August 31, 2020

In the afternoon I finished fitting the two 144” planks to the trestles, and put feet on the trestles.

The rain-water trough assembled in the shed, 144 inches long, but not yet clad in plastic.

Problem (which I knew of) with this trough is that while the length is good, the trestle extends too far towards the wall, so the throat is too far away from the wall. The purple line shows the extent of the gap. Shortening the legs would make the trough too low, rebuilding the legs is too much work. Making each side of the trough twice the width (I have the timber) means I would have a super-wide throat that would be more effective in harvesting a light rainfall during a drought.

In the afternoon widened the planks to make them 18”, then made two strips of Masonite, two more to make, to hold the plastic sheet.

Wednesday, September 02, 2020

Looking down the slope, here is the double-wide throat with a collection trough – four-folded plastic running the complete length with a plastic conduit to firm up the channel.

From the lower end. A concrete block anchors the legs for now, but A better fix of the legs to the platform needs be made, and probably two blocks would serve better.

The four “laminated” Masonite sheets. Plastic window-wrap is glued front and back, but the ends are not so well sealed.

The four Masonite sheets in place (looking like aluminium solar panels!)

The conduit with three rocks holding things down; these will not defeat strong winds. Before the gales arrive I must better fix the Masonite sheets to the throat planks.

Sunday, September 20, 2020

I don’t (yet) have to shorten the legs; I can wedge blocks under the outer legs to tilt the house-side collector closer to the wall.

Saturday, May 22, 2021

I continue to live happily and healthily using rain water from my eight-foot trough for drinking, cooking, and baking.

We have small droughts here in Bonavista. A jug of water lasts me about four days, and I get about three jugs from a five-gallon pail. Nonetheless there are periods when I look carefully at my water reserve.

We seem to receive no rain for December through March; lots of snow, but no rain. My neighbour agrees that we have just gone four weeks with no serious rain fall.

I attack this hurdle on two fronts:

(1) I have purchased four five-gallon carboys from Swyers. These are refundable jugs from a defunct bottled water supplier. I paid $10 each, I think, a small investment after two full years of not paying for drinking water. The thin-plastic green jugs I brought from Toronto froze in the shed, and two of the bases cracked. These blue carboys are thicker, and I can store them in my porch cupboard now that the shelf has been removed.

(2) I am going to record each day when I can bring a five-gallon pail indoors. Some days there may be two pails brought in, buy my definition of a rain-fall day is now “A day on which I can fill at least one five-gallon pail”.

Wednesday, September 29, 2021

This summer I rebuilt my trough, so I am in the third iteration of troughs; not counting my “drawer on the ground” discoveries. The new trough uses old plastic siding, about ten inches wide, not the four-inch used in houses nowadays. I must take photos.

The trough throat is eighteen inches wide, so it catches more of the wind-blown fall from the roof.

We are in the equinoctial gales and this month I have taken the opportunity to refill all my 3-litre jugs and also the four 5-gallon carboys I bought from Swyers in May.

My plan is to refill these longer-term reservoirs each six months.

I noticed a faint sludge in the fourth carboy, but did not think, a week ago, to soak each flask and carboy in a weak bleach solution overnight. Sigh! Next March ...

Wednesday, August 31, 2022

Tomorrow is September 1st. My plan is to refill the four carboys every six months, and further, I expect the contents to be drinkable. So tomorrow I will decant the first of the four carboys into my jugs and drink the water in my usual fashion - boiling it for everything except my little jug of milk for tea and coffee.

That means that for each major rainfall from now on, the rain water will be filtered into the carboys one by one, and this could take the passage of a month or more.

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