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conomic

evelopment

and

ater

build infrastructure. We need a change in mindset

about wastewater; we should stop viewing it as

waste and a burden, but rather see it as a resource

that could be effectively utilized to augment water

sources. And building a decentralized system for

wastewater recycling, using innovative options such

as the Decentralized Wastewater Treatment System

and Soil Aquifer Treatment, can both improve

sanitation and generate additional water sources.

Decentralized systems allow water to be used and

reused closer to where it is produced and where

it is needed. Decentralized systems can also lower

energy demand and reduce operational and mainte-

nance costs, making them especially well suited to

conditions in sub-Saharan Africa. In addition, the

decentralized treatment options and the resulting

clusters optimize the adaptive capacity of the emerg-

ing urban space by allowing infrastructure growth

to be staged in a way that traces the urban growth

trajectory more carefully. The IUWM strategy also

promotes the development of a strong watershed

protection plan where the needs and wishes of all

upstream and downstream stakeholders in the water-

shed are considered.

It is possible that this IUWM strategy could provide

sufficient water resources to meet the increasing

demand in the next 20 years. Allocation of the differ-

ent water resources is prioritized from a cost-benefit

perspective. The feasibility study estimates that for

Arua, the average unit costs for the proposed IUWM

scenario are US$0.57 per cubic metre, while the unit

costs for the traditional approach of using water from

conventional surface water sources 20 km away is

US$0.74 per cubic metre.

A unique opportunity

In conclusion, we need to recognize that global change

pressures will affect our ability to manage urban water

in the city of the future. We all live, and our cities

exist, in a rapidly changing environment. The think-

ing behind much urban planning today predates these

changes and the time has come to think fresh! We

cannot continue investing in water infrastructure that

is unsuited to future societal needs. At the same time

we have to find new ways of catering for more people,

with more needs, with the same quantity of water. All

this has to be achieved while reducing our ecological

footprints. This complicated challenge calls for a real

paradigm shift in urban water management. In emerg-

ing urban areas in Africa where water infrastructure

is still in its infancy, there is a unique but fleeting

opportunity to implement radically different urban

water systems based on the principles of IUWM. The

conclusion from the Arua case study is that IUWM

is a powerful approach to managing freshwater and

wastewater (and stormwater), and provides the poten-

tial to satisfy the water needs of communities at the

lowest cost while minimizing adverse environmental

and social impacts.

Emerging technologies that maximize opportunities for water reuse

and recycling from used water

Image:Aqua Services and Engineering, 2013

The geographic location of Arua town, Uganda

Source: Vairavamoorthy et al, 2012

Congo, DRC

Rwanda

Tanzania

Kenya

Sudan

Uganda

ARUA