In large cities of
the developing world in Africa and Asia, sewerage can often only be found in the
centre, leaving large urban and peri-urban areas unserved, including slums /
informal settlements. When sewerage exists, it is often non-functioning or
leading to poor treatment facilities. As a result, sanitation coverage in
developing cities is often low, with widespread health and dignity issues.
In the absence of
service provision, residents usually come up with their own solutions, such as
pit latrines. In peri-urban areas, there can be the possibility to install
decentralised wastewater treatment facilities, especially for new housing
developments, or as part of slum upgrading projects. Such facilities allow the
use of improved toilets and can be managed at community level.
An example
decentralised wastewater treatment facility for 5,000 residents would include:
* Flush or
pour-flush toilets (needing 1-2 litres of water per flush) in or near houses.
* Septic tanks or
related systems (anaerobic baffled reactors – ABRs) for primary treatment
(separating sludge and liquid effluent). These can be shared between houses but
then need transport through simplified sewers.
* Solids-free small
sewers to transport the effluent.
* Secondary
treatment e.g. in the form of constructed wetlands.
However, many
developing cities are susceptible to the effects of climate change, and
especially flooding due to increased rain in low-lying, coastal and/or
flood-prone areas. Many cities have seen an increase in rain and flash floods.
During such floods, one of the most significant disruptions residents have to
face is access to water and sanitation, when toilets are inaccessible, or when
treatment facilities cannot work anymore.
This is the case
for example
in many cities in
Bangladesh.
The
Challenge
The challenge is
therefore to adapt existing technologies, such as the system described above
which includes several sub-surface elements, to flood-prone conditions. Notably:
1) How can the
system still function during flooding?
2) How can it
remain accessible to residents, especially the most vulnerable ones?
3) How can
pollution be prevented?
The solution
proposed must be appropriate for the context described above, especially in
terms of capital and recurring costs, and currently available technologies.
Entry
Teams of up to 3
people, aged 18-35 on 30 September 2014.
The entry submitted
by competitors or teams of competitors must be made of:
* A concept design
for your proposal on a one A1 poster with a maximum of 1500 words and should
include at least two diagrams / sketches.
* The submission
should include the name(s) of the participants their date of birth and contact
details.
* Three copies
should be provided.
* Additionally the
competitors should also supply a CD or memory stick with a pdf version of their
submission.
Submissions must be
received by 1st September 2014.
Please send your
entries to: Edward Clarke/ SoPHE YEA, C/O Arup, 13 Fitzroy Street, London, W1T
4BQ
The Award
An in-country
technical visit to verify the applicability of the design.
