Off Grid Plumbing Solutions | Just The Essentials

Our definition of luxury items has been turned upside down in the past three weeks.  We now consider luxuries as running water and a flushing toilet without trips to town with buckets, water jugs and eskies.

This weekend was full on, with three massive days put in my our awesome family, yet again!  We managed to get all the plumbing side of things sorted this weekend which means running water and a flushing toilet!

THE BLACK WATER & SEPTIC TANK SYSTEM

Black water is any run off from the toilet and kitchen sink.  As you can imagine, this water is really shitty and you definitely don’t want it contaminating your property.

For our black water, we had a basic septic system installed which treats the waste right then and there without any interference from us.

Basically, you have a 2000L plastic tank / chamber buried in the ground, near to where your black water will run off from.  This tank has an inlet (where the waste enters the chamber) and an outlet (where the water exits the chamber) which sits higher than your inlet.

The ‘sludge’ is heavier than water, so it floats to the bottom and the water that carries the waste into the chamber sits above this.  

The ‘scum’ that’s produced, floats to create a hard crust that leaves the chamber airtight so a bacterial process can begin to break down the ‘sludge’ at the bottom.

The water isn’t as bad as you would think so it’s drained off through a series of ‘seepage trenches’ which are deep trenches, filled with gravel, with a slotted pipe running through the middle.  Our system also has matting in between the gravel and dirt to prevent that pipe being clogged.  The idea is that the water slowly seeps out, with any sneaky solids beings caught in the gravel, and the water is filtered through the ground.

Every now and then, the tank may need to pumped clean (imagine that for a job) if you have a lot of people in the house or if your grey water is also running into the system.

We’ve had to be careful where we run our seepage trenches though, because we plan on growing on both sides of the hill.  We decided to place ours on the rear hill where we plan on growing trees as opposed to vegetables which would be much more likely to absorb that water directly into the parts of the plant we eat.

Septic tank systems sound gross yes, but they’re perfectly safe if they’re installed correctly so always make sure you get a plumber to advise and install the best system for you.

THE GREY WATER & IRRIGATION SYSTEM

Grey water is much cleaner than the putrid black water we’ve just talked about so it can be used for irrigation – depending on your local council regulations of course.

In our system, water from our washing machine, bathroom sink and shower / bath is considered grey water and it all runs into a buried 100mm PVC pipe which then pokes out at the top of the hill, where it connects with clotted agriculture pipe.

This ‘ag pipe’ then runs across the hill under layers of mulch to irrigate what will soon be our vegetable patch.

Grey water irrigation is a great way to increase your water supply by using what would otherwise be waste but you do have to be careful about what you put down there.  We take special care with what shampoo, conditioner, body wash, laundry liquid, fabric softener and even cleaning products we use to make sure we’re avoiding any nasties that we don’t want near our food.

Again, make sure you check with your local council about what you can and can’t do with grey water!

THE RAIN WATER TANK SYSTEM

We went with a 5000 gallon galvanized water tank for the collection of our rain water off the shed roof.  There’s a few different options when it comes to tanks and on this one, we went with the most visually pleasing to us.  We ordered through Foley’s Water Tanks who have made their products in Woombye since the 70’s so we were able to specify exactly where we wanted the inlet and outlet.

The set up for the water tank was pretty simple.  We built a treated pine square box that was 100mm bigger than the diameter of the tank which was secured with metal pegs driven into the soil.  This was then filled with small gravel that was raked level to give our tank a solid and sharp-rock-free base to rest on.

You want to make sure you get this part right because once that tank is full, it’s going to weigh a shit load!

We used treated timber to frame up the footprint for our water tank. We then filled this with gravel before out water tank was placed on top.

We drove metal rods into the treated timber framing to hold it in place.

The guys who delivered our tank were pro’s at positioning this thing but they basically laid sleepers on the gravel to act as a track and with four blokes, they were able to position the tank perfectly.

With the tanks in place, we had to run the down pipes which collect the rain water off the shed roof into the new tank.  This was a pretty simple task that only took a couple of hours.

We decided to leave all four down pipes isolated instead of connecting them into one pipe that would run into the water tank inlet.  We figured by doing this, there is less room to loose valuable rain water collection if a pipe becomes blocked or damaged.  With a roof of our size, we were also worried that during our torrential summer storms that the pipe won’t allow the water to enter the tank quick enough and may over-flow the gutters.  It may not be the neatest of jobs but at least we have four times more chance of collecting every last drop.

Always make sure you have a water delivery booked for a couple of hours after your tank delivery – they have been known to fly away and be damaged in strong winds.

GRAVITY FEEDING THE HOUSE

Until we have our off grid solar system connected to run a water pump, we’ll gravity feed straight from the water tank.  Because our water tank is level with the shed, so long as the water level in the tank s higher than the height of the tap we’re using, we can access the water without any pump.  This has worked great for our kitchen sink and even surprisingly the toilet which takes quite a while, but does fill up itself.  Unfortunately, the height of the shower head is way past our water level so we’ll be having boiled water baths and showers in town for a little while longer.

MANAGING THE OVERFLOW

The overflow for our water tank will be directed into a small 1000L tank that Chris uses to water his fruit trees at the moment.  Without an overflow system, the water pours out the top of the water tank and can seriously damage the footing that the tank sits on.  This over time can cause tanks to tip and dump their water load.  Chris has set this up with some simple 100mm PVC pipe running into the top of his small tank which he then add worm juice to as a liquid fertiliser for his plants.  With a small garden hose on this tank, we can gravity feed the potted trees as well.

Our main water tank has an overflow pipe to fill this small plastic tank used for watering fruit trees.

Our fruit trees loving their sunny position and constant watering from the overflow tank.

Here’s the basics on our water and waste management system.