FEATURES
•
“A sanitary drainage
system design and
installation by a plumber
must comply with
SANS10400-P.”
Concrete drainage pipes
that have been laid at
Heathrow Airport, UK.
•
place, in layers of about 150mm thick, and each
layer is to be compacted to the same density as the
adjacent soil.
Always refer to the engineer’s specifications (if the
design was done by an engineer), as well as the
pipe manufacturer’s specifications, as these may
vary depending on application.
The above mentioned is relevant for areas
where there is no traffic, and in traffic-bearing
installations, the pipe must be protected with a
concrete slab over the 300mm cover.
49
WHAT WILL HAPPEN WITH NEW TECHNOLOGY LIKE
NO-FLOW OR LOW-FLOW DEVICES?
These types of fixtures are still not officially approved and
therefore will not be specified in SANS10400-P, but it is
important for the future of drainage to find solutions for
our water shortages, as well as other alternatives.
One solution may be the adaptation and development of
systems to use greywater, and low-flow toilets and urinals,
which will also significantly alter the design and workings
of a drainage system, as additional elements would need
to be specified and implemented, such as treatment
facilities per property. There is a new SANS document
forthcoming that will address water conservation, which
includes lesser flow rates for fixtures.
An interesting concept was discussed at the end of
last year between the Water Research Commission
and the Department of Science and Technology as they
evaluate decentralised wastewater treatment units
even for residential units. This would essentially mean
that sewage would be treated at the source rather than
conveying it to wastewater treatment plants that are
already unable to handle current volumes.
WHAT ELEMENTS DOES THE INSPECTOR LOOK AT AND
WHY DOES THE INSTALLATION TYPICALLY FAIL?
It is both a regulation and a legal requirement that a
building inspector must/shall inspect a drain before
www.plumbingafrica.co.za
A typical drainage
installation for a
public restroom.
May 2019 Volume 25 I Number 3