Integrated Urban Water Management, by Kala Vairavamoorthy

Integrated Urban Water Management (IUWM)

African Water WeekDakar 27th May 2014

Kala Vairavamoorthy

Patel College of Global Sustainability

UNIVERSITY OF SOUTH FLORIDA

~2.5 Billion without access to improved sanitationd

~780 million without access to improved water

Bad News: Developing World

Managing urban water will become more challenging in the future

• 155,000 persons per day

• 90% in developing countries

• ~90% in urban areas

• ~850,000 per week in urban settings

The Urban Arithmetic for 2050

Growing but also ‘Growing Up’

Source: UN (2003)

Growth in emerging towns -Opportunity to do Things Differently

Source: World Bank (2010) World Development Report 2009 Reshaping Economic Geography , second edition, pp. 35

Opportunity to do Things In Africa and Asia

Shenzhen

Fishing village of several thousand

City of 7 million – big in electronic manufacturing

1980 Today

Rapid Urbanization in Africa and Asia

Need to think differently

IUWM is not a methodology but a mindset - a different way of thinking

IntegrationProductive UseBeneficiation

Doing more with less ‘Integration the key’

Holistic systems approach

to the urban watershed

Surface water

Demand management

Leakage management

Stormwater/ Rainwater

Black water

Groundwater

Grey water

Productivity requires an integrated perspective of the urban water cycle

Integrated modelling allows us to connect all flows with productive uses

SURFACE WATER/GROUNDWATER/DESALINATION)

WATER SUPPLY

COMM/DOM/IND/USEIRRIGATION

GREYWATER REUSE

WASTEWATER TREATMENT

RECEIVING BODY (SUSRFACE/GROUNDWATER)

RAINWATER/ STORMWATERHARVESTING

POTABLE WATER

RAIN/STORMWATER

GREY WATER

BLACK WATER

KEY

RECLAIMED WATER

TransitioningExploring alternative urban water solutions to rapid population growth

Water demand will at least double until 2035

NAIROBI

Typical solutions - import more water to meet growing needs

• Unit costs of US$ 0.36/m3

New

GW

Existing

Demand

(2010)

637X103 m3/d deficit

New SW-1

New SW-2

Demand

(2035)

Improving productivity measure reduces unit costs

• Unit costs of US$ 0.31/m3 (cf. to 0.36)

Demand

(2035)

New SW-1R

ain

wat

er

har

vest

ing(

Clu

ster

)

New

GW

Dem

and

Mgt

.Leakage

Mgt.

Gre

ywat

er(C

lust

er)

Demand

(2010)

637X103 m3/d deficit

Further productivity measures can postpone investments

• Unit costs of US$ 0.40/m3 (cf. to 0.36)

Rai

nw

ater

h

arve

stin

g(C

lust

er)

New

GW

Dem

and

Mgt

.Leakage

Mgt.

Gre

ywat

er(C

lust

er)

Demand

(2010)

637X103 m3/d deficit

Rec

laim

wat

er(C

lust

er)

Rai

nw

ater

(H

H)

Gre

ywat

er(H

ou

seh

old

)

Demand

(2035)1.21

WN

It’s already happening: Namibia

Reclaimed Dam Water Groundwater

Domestic

Consumers

Industrial

Irrig. -Parks

WW Treatment

26% 66% 8%

45%

7%

6%

10% Unaccountedfor Water

WW Treatment

Irrig. - Fodder

River

Reuse for Irrigation

Re

use

fo

r d

rin

kin

g w

ate

r

Reclaimed (old)

13%

83%

Consumed38%

26%

90%

Security through diversity

Conveyance

Treatm.(pump)

Treatm.(process)

Local catchment Import NEWater Desal Total

0.480.42

1.03

kw

h/m

3

0.56

4.09

NEWRI 2010

Unconventional water sources: more energy intensive

bank filtration,

soil-aquifer treatment, constructed wetlands,

hybrid systems

Natural systems can help close the water cycle

River

Natural systems can help close the water cycle

$0.067/m3 (cf 0.28/m3)

0.012 -0.024 $/m3

(cf 0.05-0.15 $/m3)

(0.17 $/m3)

Lake Bank

Filtration

River Bank Filtration

Primary Treatment

and/or Constructed

Wetlands

Stabilization Ponds

Water for Irrigation

Riv

er

Dam

Reservoir

Ecohydrology

Low Energy – Water Efficient’ Closed Loop

Soil Aquifer Treatment

Artificial Recharge Recovery

Kibera

Nairobi Dam

Ngong River

Greywater from unservicedhouseholds

Polluted runoff from streets

Overflow from pit latrines

Flows from Kibera pollute Nairobi Dam No longer used as a water source

Cost for provision of drainage and sanitation for Kibera

• EAC US$ 1.0M

Condominium sewers

Condominium sewers

DEWATS

DEWATS

Potential water resources after slum improvement

• Yield 17,300m3/d

• Cost of water (0.16$/m3)

• US$800,000/year reduction

SUDS

SUDS

Urban water infrastructure provision to Kibera benefit all of Nairobi

Ben

Manage water supply, wastewater & stormwatertogether (one urban water cycle)……. and think creatively about what could be your water sources (and don’t focus on the obvious ones).

Take home message

(educate future urban leaders on the integrated perspective of the urban water cycle and contextualize each component of the water system within this perspective)

Need to recognize that main challenges are political and institutional in nature

Path to

Implementation

Political &

Institutional Barriers

Need collaboration, cooperation, and coordination between institutions

The water sector can’t do it alone

Land plannersArchitectsDevelopers

Gov’t officialsFinanciersEnergy experts

We need to break down barriers

Bogota, Colombia

Issue:

• pollution of upper Rio Bogota (tanneries)

Key players:

• Association of tanners, Regulator, Local government, NGO, University,…

Outcomes:

• 1/2 of small enterprises implemented cleaner production principles removing 90% pollution

We need to put water in the minds of people?

Create a favorable enabling environment (institutional landscape, regulations etc.) that allows the effective and sustainable urban water management

Take home message

Think about Harvesting

Looking from downstream up

Perspective of productive use and beneficiation

Productive Use Beneficiation

Quality

B

Quality

AQuality

C

Grey water

Brownwater

Urine

Solid waste

Surface Water

Ground Water

Rain Water

Energy

Potable

Water

Reclaimed

non-potableIndustry

Use

HygienizedSludge

Nutrients Bioplastic

These perspectives lead to a more decentralized type of thinking?

Decentralization well suited for:

• Energy recovery (heat recovered and used close to source)

• Minimizing energy consumption (for moving water)

• Source separation (to maximize nutrient recovery)

• Adjusted growth (to deal with rapid growing cities)

• Increased resiliency (dampens the propagation of failures)

Water machine to deal with growing cities - Qingdao, China

• 12,000 PE clusters

• Source separation and water quality matched to intended use

• Net energy positiveWater

Resource

Look for opportunities to create new paradigms (not extended old ones)

Formalised

Water System

Small scale providers

Growth

Decentralized

community based

Expansion of existing

system to serve new

demand

New demand

Qujiang New District

North lake

South lake

Associated

wetland

District

wastewater

treatment

plant

District wastewater

network

District storm water

drainage

(Secondary treatment)

(Tertiary treatment)

(Regulation

lakes)

Gardening

Forestation

Miscellaneoususes

Car washing

• New cluster for 10,000 PE

• Environmental buffers used before reuse

• Clusters boundaries determined through spatial optimization process

Cities ring-fencing central core and decentralizing in new areas - Xi’an

Xi’anCentral

Cities ring-fencing central core and decentralizing in new areas - Xi’an

Siyuan College

• 18,000 students

• Decentralized water and wastewater

• 50% less potable water

Xi’anCentral

Quick growing emerging towns

Exploring opportunities to do thinks differently in emerging cities

UGANDA

C1

C2

C3

C4

C7

C6

C5

Look for opportunities to create new paradigms (not extended old ones)

Semi-centralized is cheaper?

Average Annual Costs

3,787,000 US$Average Annual Costs

5,148,000 US$

One size does not fit all – Different solutions for different drivers & applications

Centralized Decentralized

Cluster In SituSemi CentralizedLarge Scale

A Continuum of Options

EXTREME EVENTS –

RESILIENT WATER SYSTEM

Driver for water management should be beneficiation –maximize value added

(institutions & regulations to support and not hinder)

‘All water is good water: fit for purpose’

Take home message

(educate future urban leaders on all benefits of water – public

health, aesthetics, economic development, green economy)

Transitioning

Graph Theory Transition Systems

Existing System

Future System Based on Old System

Future System Totally New System

Transitioning

0 10 20 30 40

0 10 20 30 40

0 10 20 30 40

0 10 20 30 40

0 10 20 30 40

0 10 20 30 40

0 10 20 30 40

0 10 20 30 40

0 10 20 30 40

0 10 20 30 40

0 10 20 30 40

Sempewo, J., Vairavamoorthy, K. and Grimshaw, F. (2010)

We need Champions of Change

Train new urban leaders!

Training program needs to be holistic and promote integration

Technology Selection

Building Effective Institutions

Stakeholder Engagement

Economics and Finance

IUWM Toolbox

IUWM Diagnostics

Water Balance Model

There are many technologies suited for developing countries – but what are they?

What technologies exist to allow me to

reuse & recycle?

How can I capture nutrients from my

water?

What technologies will help me

generate energy from my water?

What technologies exist to help me

harvest stormwater?

What technologies will help me convert

faecal sludge into money?

?????

Greywater Treatment:Household

DEWATS

Horizontal Flow WetlandsAlgal Culture Ponds:

Harvest Micro-algae

Fecal sludge into safe fertilizer:

LaDePa machine (Durban)

We need a catalogue to help us understand what technologies exist (and where/when to apply)

Medium Level for Senior Managers

Expert Training for Managers & Practitioners

A strategy that cascades change

Choices Before Us

What You

Know..

What You

Don’t Know..What You

Know..

Stay in Lane

Business as Usual

Try Harder

Spend More for Traditional Sys

Paradigm Shift

Truly Different Approach

Kalanithy [email protected]

Thank You

Global Challenges, Global Research, Global Solutions