Why don’t more Kiwis don’t invest in economical rainwater harvesting systems for their home or business properties? This question is posed by Justin Jordan of Timbertank Enterprises.
"The public and industry want to harvest rain water as being
good for the environment and to save money, and industrial concerns
are also keen to reduce waste water consents and costs," he says.
"However, most Councils do not see why the public should harvest
rain water when town supply is so cheap.
"The public needs more guidance from Councils as to the volume
of storage they are happy with, so responding to public keenness to
harvest rain water. It's a disgrace that over 50% of potable water
in New Zealand is flushed down the loo", he says. "We simply can't
afford to keep on this slippery path.
"Currently Councils feel the burden on water stocks when we have
a dry spell - small tanks run out and people switch to town supply,
when town supply is running short too. It's a double whammy. So we
need to slow this water cycle down.
"In dry summers, people are calling out for rain, then when it
comes, they don't conserve it. But if people had at least a 20m3
tank at home, or a decent installation - say 100m3 - at their
industrial site, there would be a huge saving of a precious
resource."
The key question to be answered is, how much water storage is
enough? And that depends on the needs of the water user. Enquiries
from industrial concerns who want to become better 'green' users
and cut down on their water use - particular wastewater, are
resulting in Timbertanks increasingly providing effective rainwater
harvesting systems to reduce use of Council provided water.
"We have developed a system using downpipe surge collection to
divert rainwater from different shaped roofs into holding tanks,
which are then piped to be used for flushing lavatories etc.
"We have recently done two major installations in Auckland - one
at the Auckland Prison in Mt Eden, with two x 100m3 holding tanks,
the other at Auckland Domestic Airport, with a 70m3 tank."
Part of the investment problem is having economical systems
available. Justin says costs vary according to the size of the
installation, but a typical downpipe connection is estimated at
$600, plus the cost of the holding timber tank and plumbing. For a
standard 20m3, 3.5m diameter tank for home use, cost would be in
the vicinity of $12 - 15,000. The company is also able to offer
elevated gazebos over water tanks as an attractive garden
asset.
"More rain falls than you could ever use, so the key to the
success and the payback is to install the biggest tank you can
afford," says Justin. "I believe that flushing your loo with
premium drinking water is almost criminal! Why not save the
environment and money at the same time?
"Depending on the installation, a water bill can reduce by at
least 40% and up to 60% in some cases - payback is 5-7 years. It is
particularly cost effective for industrial situations. And for
industrials we would expect their use to grow, so Timbertank
systems are planned to allow tanks to be rebuilt to a larger size,
for a small cost."
The photo shows a different approach to utilising a rainwater
harvesting tank at the Kerikeri Riding School. A viewing
platform/gazebo has been erected overlooking the equestrian
dressage arena on the newly constructed 45m3 Timbertank. Water is
collected from the roof of the adjacent indoor arena and piped to
the tank.