I could literally talk about water all day long. Where it comes from, how much we use, bottled vs tap, you name it, I usually have an opinion. When I see massive condo developments in downtown Toronto, my first thought is where are they getting all the water to support these residents? And subsequently, how are they dealing with the waste. My grandfather was a civil engineer so I guess I come by it naturally.
I’m not sure when this obsession started but I remember researching rainwater collection when we decided to build our cottage near Lake Erie. It was 2003 and there wasn’t much information out there that wasn’t based in either Australia or Texas. Which makes sense. Necessity breeds innovation and areas effected by drought were motivated to come up with new and better ways to collect as much rainwater as possible. I had hoped to instigate some system of collection off our roof at that time but I hit a few snags. Our small-minded contractor didn’t know how to help and the filter systems were based on Australian eaves troughs and weren’t compatible with our systems. I admit I didn’t force the issue at the time because, well, the cottage is next to a lake. Water is not hard to come by and it was just a cottage.
But now we live here full-time and my drive to collect water is back. The main reason is the expense. Because we live in the country, we are not on any municipal water system. Our water has to be trucked to our house from a water depot in town and placed in our cistern. Not only is there an environmental impact of gas emissions from the truck but also, our water prices are dependent on the price of gas. As a result, our water is almost 3 times as expensive as water supplied to houses through municipal pipes. I’m told the average person uses about 90 gallons (about 400 litres) a day. Toronto water costs about $0.016 a gallon or $1.44/day. In the country, we pay $0.045 a gallon or $4.05 a day per person. So in a year, a city dweller could spend $525 per person. For us, if we used that much water, we would spend $1,478 per person. Due to the fact that we changed our toilets to dual flush and our taps and washers to low usage, we only use between 30 and 40 gallons a day for two people. But we have an acre of land where we have planted new trees, flowers and vegetables. And plants prefer untreated water anyway. So you can see why we have decided to put the effort into rainwater collection.
If you are wondering, we are not right on Lake Erie so pumping water from the lake isn’t an option for us. In addition, because Lake Erie is so shallow you have to use very long pipes to get deep enough for the cleanest water.
Rainwater collection can be as simple or complex depending on what you are using the water for. This is because rainwater, as it pours off the roof, is not the cleanest stuff. On its journey across the shingles it picks up all sorts of detritus (animal poop, leaves, pollen, sticks, asphalt bits) that must be filtered out if it is going to be used for anything other than plants. And even for the simplest of rain barrels it is best to filter out the debris or you will have a very messy and moldy barrel to clean out each fall.
For our garden, we have a mixed bag of new and recycled barrels daisy chained together to maximize collection. As one overflows, the next one fills up until finally the last one over flows into the lawn. I’m hoping some day to clean this up into one cistern with a bigger capacity. With a small pump we could use this water for the garden and washing the car if we wanted. Right now I get my exercise filling watering cans and walking them all over the land.
This year we have started a new experiment (see image below) to start collecting water for the intent of drinking it. To say that I have studied how this should be done is an understatement. Over the last 15 years I have read most of the documentation on the best ways to do it. Interestingly the science hasn’t changed that much. Each country has their rules and recommendations but the end result meets the same requirements. We just started this Spring so we are still sorting out the pipe connections, making sure they don’t leak and that they can handle light and heavy flow of water. As we already have a below ground concrete cistern that is connected to our household pipes, the idea is that as the above ground tote fills up we will empty it into our household cistern.
To give you an idea of how much rain we could collect the calculation is: roof square footage x amount of rain x 0.623). So 1″ of rain off one side of our barn roof (approx. 525 sq ft) would equate to 327 gallons. On average our location gets 35″ of rain per year so we could potentially collect 11,447 gallons of water off a small roof. We consume around 14,000 gallons a year. As we add roof surface we can begin to collect more. In the meantime, we will make sure our new system can purify what we do collect.
Even though water is cheaper in the city, I encourage everyone to divert or collect rainwater. At a minimum you need to divert your eaves troughs away from the house. It is better to send this water into your lawn or garden as it relieves the pressure on the storm drains. If you want to collect it so you can use it to water your plants, there are all sorts of kits to get you started. For basic rain collection you will need:
- Rain barrel with screened opening on the lid.
- Downspout directed straight into the opening. You could add a seasonal diverter as well. See below.
- Overflow tap with hose leading away from the house.
- Tap at bottom of barrel for watering can. Make sure the barrel is high enough off the ground to get the can under the tap. Some barrels come with stands or you can make something out of concrete blocks.
For our rural experiment of collecting water to eventually drink, the requirements are a bit more stringent.
- Metal roof is preferred – asphalt roofs shed too much debris.
- Gutter guards – to keep leaves and big debris from clogging your eaves trough.
- Seasonal diverter – because we live in a country with winter we need to be able to turn off the collection of water. Otherwise, water in the tanks can freeze and thaw, cracking the plastic. Winter mode sends any water down a regular downspout into the lawn.
- Basic filter – for large debris that get past the gutter guards. Can’t have too many filters. No one wants to clean a cistern more than necessary.
- First Flush Diverter – this is considered essential according to the government recommendations. This diverter collects the first few gallons of water, rinsing of the roof of nasty bacteria resulting from animal poop, and sends it into the lawn.
- Final filter – for the really small stuff and to keep the mosquitos out of the tote.
- Cistern – rain barrels come in all shapes, sizes and price range. For our experiment, we chose a 275 gallon water tote. To prevent algae from growing, all barrels must be opaque. The tote we bought was white so we wrapped it in black plastic. Solves one problem but now we need a water level gage as we can’t see how much water is in the tank.
- Water overflow tap– in case you don’t use the water before the tank fills up.
- Water level gage
- In house water purification system – this includes a sediment filter and a UV filter. UV treatment is a non chemical process that removes bacteria from the water. This is the most critical step in the process and usually the most expensive.
If you are interested in knowing how our experiment works, I will be posting as we go along. Sign up via email to get notification of new posts.