Rainwater Tanks and Pumps.Done Right.

Mains backup

Many tank systems include a mains switchover valve so you keep water when the tank runs low. We install and test these.

Sizing and placement

Size depends on roof area, rainfall, and how you will use the water. The tank needs a firm base, access for cleaning and a clear path from the downpipes.

Backflow and rules

Connections between tank water and household plumbing must stop tank water getting into the mains. We install the right devices and follow the rules.

What to settle before installing

Where will the tank sit, what will the water be used for, and does it need a mains top up? Tanks connected to indoor use need backflow protection and correct plumbing. Pumps should be sized for the pressure and flow you need, with protection against running dry. Check council and water authority requirements before you buy a tank.

Pump and tank problems

A pump that will not prime, cycles on and off, runs dry or makes noise points to air in the line, a leak, a blocked inlet or a worn pump. Tanks collect sediment and need cleaning every few years.

Check the first flush diverter and gutters each season.

Water quality and use

Rainwater from a roof can carry leaves, bird droppings and dust. A first flush device and filters help. Rainwater is often used on gardens and for toilets and laundry. For drinking, the health advice is different, so check the guidance from the Victorian Department of Health before drinking tank water.

Gutters and the roof material also matter, so ask your plumber about both.

Gutters, first flush and filters

Clean gutters and a leaf guard help keep debris out. A first flush device diverts the first dirty water from each storm. Filters at the pump and the tap protect fittings. Clean them on the maker schedule.

Choosing what the tank will be used for

A tank can supply the garden, the toilets and laundry, or the whole house. Each use brings different requirements. Garden use is simplest. Connecting a tank to indoor fixtures involves backflow protection, labelling and a way to switch back to mains water when the tank runs low. Decide the use first, then look at size and pump.

Your local council and water retailer may have rules or rebates about tanks, so check before you buy.

Pumps: types, noise and power

A pump moves water from the tank to where it is used. Pressure pumps run when a tap opens, while some systems use a pump with a pressure tank to reduce cycling. A pump that cuts in and out rapidly, even when no tap is on, usually points to a leak or a faulty valve. Noise matters if the pump sits near a bedroom, so ask about placement and a solid base.

Pumps need a clean water supply. A filter or a first flush device keeps leaves and grit out.

Keeping a tank healthy

Keep gutters clean so leaves do not wash into the tank. Check the screens on the inlets, since mosquitoes can enter through gaps. Look at the overflow and make sure it drains away from footings. Every few years, check the tank floor for sediment and have it cleaned if there is a lot.

Roofs with lead flashings, treated timber or certain coatings are a question for the roof's maker or a roofer before you collect water for drinking.

Mains top-up and what happens in a dry spell

If the tank runs low, a mains top-up valve can add water so your toilets and washing machine keep working. This device has to be installed correctly so the tank water and mains water never mix. It is part of the job to ask about, not an optional extra.

Tank size and your roof

The amount of water a tank collects depends on roof area and rainfall, and the amount you use depends on what the tank supplies. A small garden tank fills quickly and may overflow often. A tank connected to toilets and laundry needs enough volume to last through dry weeks. Ask a plumber to help you size it to your roof and your use rather than picking the biggest tank that fits.

Check the council rules about tank placement, setbacks and overflow before you buy, since some sites need a permit.

Overflow, siting and the neighbours

A full tank overflows, and the overflow has to go somewhere safe. It should connect to the stormwater system or a legal discharge point and not run against a footing or across a boundary. The tank base also needs to be level and firm, because a filled tank is very heavy.

Pump faults you can spot early

A pump that runs without water, cycles on and off, hums without moving water or leaks at the housing is telling you something. Most causes are an empty tank, an air leak in the suction line, a blocked filter or a worn pressure switch. Switch the pump off if it is running dry, because that can damage it quickly.

Mains top-up and backflow

If a tank is topped up from mains, backflow protection prevents tank water entering the supply. This is regulated work for a licensed plumber.

Ask for the compliance paperwork.

Pump noise, power and maintenance

Pumps need a dry location, and filters and strainers need cleaning. Plan for power cuts and dry-run protection.

Check the pump manual for service intervals.

Choosing a tank and a pump

Tank size depends on roof area, rainfall, and what you plan to use the water for. Pumps need to match the demand, such as irrigation or toilet flushing. Check the pump's flow and pressure rating.

Ask the plumber about maintenance, first flush devices and mosquito-proof screens.

Guides worth reading

• Rainwater Tanks and Pumps: What to Know Before You Install
• New Home Plumbing: What Owners Need to Know
• What Is Backflow Prevention and Do You Need It?

Related plumbing services

• Water Filter Installation: Under-sink and whole-house water filter systems installed.
• Dishwasher and Washing Machine Installation: Dishwashers and washing machines connected to water and waste.
• Emergency plumbing is available 24 hours a day, 7 days a week

Talk to GSA Plumbing Services

Call 0401 041 103 or send an enquiry on the contact page. We work across Geelong, Melbourne and surrounding suburbs.