Greywater and Rainwater
Perth and Fremantle - Australia
Water Capture - Mark Harland


Turning swimming pools into rainwater tanks is becoming increasingly popular.

As kids grow up and leave the family home that well used pool now sits there requiring regular maintenance. Not only that, the amount of mains water required to keep the pool topped up is huge. There is the cost of chemicals, running heaters and pumps and the time required for general upkeep.

The cost to either remove the pool or demolish it can be very expensive especially if there is limited access to the site. There are the additional costs of filling the void left by the removal of the pool.

Water Capture can turn that unwanted Swimming Pool into a Rainwater tank. We look to divert  some of the downpipes  from the homes roof into the pool via a filtration process.  A decision is made on where the home owner would like to use that Rainwater, options include: Outdoor taps, garden irrigation, flushing toilets, supply to washing machine, or for the Whole home.

Based on previous conversions the minimum price would be $20 000.

Quotes are time consuming therefore we need to charge a $220 fee for a site visit and quote. If you proceed with the pool conversion the fee will be taken off the cost.

Before - City Beach swimming pool conversion to rainwater tank

After - City Beach swimming pool conversion to rainwater tank

Pumps and controllers can be sized and installed inside the pool, all the pipework and services will be hidden away either underground or inside the pool. Basically it is just another form of underground rainwater storage.

We provide several options depending on the type of pool you have. Structural lids can be placed on concrete pools no matter what size or shape the pool is. Fiberglass pools we generally look to use a membrane liner with plastic cells wrapped in geotextile.


Thank you for the fantastic job ‘Water Capture’ did on converting our pool into a rainwater storage tank. It was nice to see such fine workmanship, attention to detail, and great execution of the job. The finished job looks amazing. We were particularly impressed with the way you left the site each day, tidy and organised. 

Thank you also for keeping us constantly informed of what you were doing and making suggestions along the way as to how to best benefit from the conversion - such as using the collected water for the downstairs toilet.

We look forward to watering our garden in the summer months with the collected rainwater and the subsurface irrigation system you installed, GUILT FREE!! 

We will be recommending you to anyone we meet that is looking to do the same thing! 

Best wishes with your growing business.

Jay and Marlene ~ City Beach

North Fremantle - Swimming Pool Conversion to Rainwater Tank
- Before, During and After Photos

North Fremantle Swimming Pool Conversion to Rainwater Tank - Before, During, After Photos

It was a pleasure to work with Mark in building the rainwater tank using the Versitanks and that the finished result has more than met our expectations - not only have we significantly increased the size of our vegie garden but we have had sufficient water to carry our entire veggie garden (which consists of three 'plots') through what was a very hot and dry summer. We also decided to build a small pond in which we have added some water lilies and fish. This too has been a source of great delight to my wife and myself. The little top-up water required is supplied from the rainwater tank.

Just yesterday as we were planting out a mix of broccoli, beans, sugar snap peas and chard my wife remarked on the joy and satisfaction these changes resulting from replacing the swimming pool with the Tank and garden have given us.

John ~ North Fremantle


We have Engineers design the steel sub-frame required to hold the lid. Customers have many options with how to cover the lid. Paving, concrete, garden beds, lawn, decking or artificial turf are some of the options available. The next step is to submit a “Building Application” to your local Shire. Every Installation is different, depending on the spans involved, the finished lid and its load bearing and whether it is trafficable.

Structural lid of swimming pool to be converted into a rainwater tank


With fiberglass pools where we don’t have the concrete for load bearing, an option is to use plastic crates wrapped up in a membrane liner. The liner is protected by multiple layers of geotextile and acts to keep the rainwater as one body. The plastic crates serve to give the tank its structural integrity and volume. The pump can still be hidden away inside the crates and once covered over with enough fill anything can be put on top – paving, concrete, gardens etc. It will even be trafficable. Any void sections around the edge of the pool can be filled with clean fill. We can also cut crates into sections to use as fill.

A plastic cell is placed in the swimming pool and forms the structure to hold the rainwater

Plastic cells that hold the rainwater are wrapped in a liner and then covered with soil

Stormwater Retention/Infiltration and Underground Rainwater Storage
The plastic cells wrapped in a liner is also an independent method of Rainwater capture. Rain water from Roofs, hard scaped areas, driveways etc can all be diverted to the below ground cells. Various degrees of filtration can be applied depending on where we want that rainwater directed. Water from driveways would be suitable for garden irrigation, rainwater from the homes roof can be directed inside the house for toilet flushing, outdoor taps, washing machines etc.  When building a new home or lots with large garden areas this is a great way to get a large rainwater tank below ground. So whether it is acting as a large soak well (Infiltration, without the liner) or a storage tank for rainwater (Retention, with liner) it can work out to be a much cheaper option than traditional methods of underground rainwater storage/drainage.

With all underground water storage there are some important considerations. It needs to be light proof and it needs to be mosquito and bug proof. Basically it needs to be sealed apart from letting water and air in and out of it. We need access to pumps and we require an overflow facility for excess water to escape. The tank also needs to breathe. As water levels rise and fall so do the air volumes.

1. Rainwater Down Pipe
2. Leaf/Silt Trap
3. Re-use Tank
4. Infiltration Tank
5. Stormwater Drain
6. Pump
7. Sprinkler

City Beach Conversion of Swimming Pool into a Rainwater Tank
~ Stage by Stage
Empty swimming pool

Galvanised steel bearers dynabolted to the pool wall as the support for the lid

18 mm Fibre cement sheeting glued and screwed to the steel frame

Sheeting completed - new brick edging around the pool

The Inspection hatch to the new Tank

New brick paving around the edge, dripline irrigation to garden beds and artificial turf on the pool lid



Greywater Perth Summer Special
This Month's Rainwater Tank Sale