Rainwater Harvesting From Portable DIY To Professional Home Setup

Rainwater collection system inspiration by Heidi Mergl Architect

The first warm spell of the year has arrived - what a delight - Easter weekend in the sun. I would have thought most of us are very happy about this and the warmth is just wonderful but everything has its downside. Looking around our garden I see the poor plants letting their heads hang down and I feel very much obliged to give them water. So I thought after we said all the good things about the sun and talked about winds and air flow it is time to catch some rainwater. Maybe even inspire some DIY, not just you but myself too, after all my plants are very much in need for me doing something and not just resting this bank holiday weekend, haha.  So let's see what one can do even if you live in a big city! 


All you need is a rainwater collecting surface which is often a roof and a bit of space to store the water. I know what all of you are thinking, where is the space supposed to come from, we have to store our treasures in storage units! Well, ok here are some fun projects without roof space first of all even though I was thinking to use my little garden shed roof [sketch to the right].

I found the ideas below via my Pinterest and of course these images are linked to the source if you would like to know more. However I think they are pretty much self explaining as all you need is pictured. Have a look!



Rainwater collection system image via Pinterest
Rainwater collection everywhere

The above image is the most portable system I could find. I think this is even good when camping, or we could just pop it up on window sills or out our front door when it rains and so on. And as you can see the kids can get involved adding some artwork to it. The one on the right caught my eye as it simply looks total fun. But take a closer look at this DIY, it does not just a collect water but also a provides a double use. The water is being caught and in a first step used to wash hands or veggies or whatever. The water then goes on to be used a second time by having the drain watering the plants below. Love this!

Ok, ok some you might go on and say, yes but this not a permanent solution what about dirt and leaves and so on. You are right and I see what you are saying but I don't think these are permanent constructions they are more or less systems to pop out when rain is coming down. To save a little and for this these systems are fair enough. 

Rainwater collection system image via Pinterest
Rainwater to wash hands and the drain water waters the plants - marvellous DIY

After all sometimes there is not enough space or even rules to think of when doing this. 

Here are 6 mistakes to avoid when harvesting rain water


1.  Forgetting to make sure it’s legal in your area.

2.  Using the wrong kind of barrel (the wrong kind will leach dangerous chemicals into your water) - hence the above water or milk container

3.  Buying expensive barrels. If you search hard enough, you can find them used.

4.  Not setting up a system for getting your water out (such as a spigot or pump).

5.  Not keeping your barrels covered (with sheets, screens, or even cooking oil).

6.  Forgetting to let rain rinse your roof for 10 minutes before collecting rainwater.


Rainwater harvesting system image via Pinterest
Rainwater harvesting to water the garden


However, if you want to do more and have the resources left and above are systems to start the planning process. 


The system to the left is an underground system to harvest rainwater for the garden. It is indeed just that but if you have green or even a homestead this could make a whole lot of a difference. 


The system above is way more sophisticated compared to the ideas above but it goes to show what else could be supplied with and would make good use of rainwater. I mean watering the plants is the obvious thing but rainwater is also more than clean enough to bath, wash the laundry and flush the toilet besides looking after your pets and plants. There are various systems on the market and they all have the same basic components – a filter, tank [size depends on what you would like to cover] and a pump to fight the gravity from the tank, which is often underground, to your toilet or washing machine. This can all be connected to your existing plumbing and you will keep a connection to the water mains for that period where the rain just doesn’t want to come. I am happy to help with more, just leave a comment. 


Anyway, for us it will be the shed roof  and I drew up the following idea. The shed is just a timber box that we set up ourself but most importantly it has a pitched roof with a nice waterproof membrane. On rainy days I can see the water dripping of the roof edge and disappearing into the ground but I am thinking of fixing it with a little gutter and position a barrel at the end. I should really get going on this, don't you think?!


Simple and very much in the spirit of Easter,

Have a great weekend,

Happy Easter


Rainwater harvesting ideas by Heidi Mergl Architect

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