Compost Toilet Trial Report - Ministry of Civil Defence and ...

2 Background
2.1 Canterbury experience
The Canterbury earthquakes (September 2010 and February 2011) highlighted the
vulnerability of sewerage systems to disruption during an earthquake. Temporary toilet
solutions in Canterbury were mainly a combination of backyard long drops, port-a-loos
and chemical toilets. The Canterbury experience revealed some significant
disadvantages to port-a-loos and chemical toilets, as shown in Table 2.1
Table 2.1: Key difficulties of port-a-loos and chemical toilets during Canterbury earthquakes 1
Port-a-loos
Supply unable to meet demand
Some people were required to walk quite a
distance to use a port-a-loo
Significant odour issues
Easily and regularly vandalised
Safety issues. Some were tipped over while
people were using them
Lack of water and hand washing facilities
(often not working)
Labour intensive as they had to be pumped
twice a day
Public health issues. Not being cleaned
regularly for the number of people using
them.
Impact on psychological well-being of
community with the large number of people
using one port-a-loo for extended periods of
time.
Chemical toilets
Use of chemicals. Misconception that
chemicals are making waste “safe”. Some
of the chemical used are only odour
suppressants.
One size fits all approach. Often the seats
are designed overseas and are quite small
and were not suitable.
Takes a significant amount of time to source
enough toilets to meet needs
Waste needs to be dumped in large
communal tank, which users found difficult.
Potential health issues from presence of
tank on streets.
Tanks needed to be pumped regularly, often
daily.
The Canterbury experience also highlighted the lengthy restoration times of sewerage
systems. A situation that is likely to be exacerbated in Wellington by the significant
access difficulties expected after a significant earthquake 2 .
2.2 The compost toilet project
In 2012 WREMO was approached by compost toilet proponents, Matthew King of
GreenEarth Developments and Gary Williams of Waterscape, to discuss compost
toilets as a suitable option for the Wellington region in an emergency. Compost toilets
were proposed as an option following the Canterbury earthquakes and received some
support and uptake at a community level.
1 Anecdotal comment (community meetings in Christchurch)
2 Lifeline Utilities Restoration Times for Metropolitan Wellington following a Wellington Fault Earthquake (Wellington
Lifelines Group Nov 2012).
2