Technische Universitaet Muenchen – Institute for Advanced Study

STOA Annual Lecture, Brussels, 29-11-2011

Managing Water Supply and Sanitationin a

Crowded World

Peter A. WildererMunich, Germany

problems & solutions

7 billion people on Earth

more alarming is compression of people in specific areas

> 60% live in coastal zones

> 50% live in cities

the consequence:

amplified by:

• globalization of „western“ lifestyle

• progress of complexity

demand:

• water• food• energy• land• etc.

pollution:

• air• water• soil• mindset• etc.

local increase of demand and pollution

on the other side

locally available resources are limited

pollution and over-abstraction

deteriorate quantity and quality of resources

sequence of causes and results

the traditional approach to solution:

increased exploitation of natural resources

lossof

eco-system function

what did James Lovelock say?„eco-system function warrants life on Earth “

- control of surface temperature

- control of precipitation paterns- ability to absorb disturbances (resilience)

we are faced with global crises: the big 4

ecosystem dysfunction

destabilization(societies & economies)

deficiency of resources

climate change

all 4 crises are delicately interwoven

balancingclimate

perservingecosystem function

satisfying demands

stabilizingsocieties & economies

to keep our eco-socio-economic system stabel

all 4 crises are to be solved

simultaneously

concerted action is required to reach solution

ecosystem dysfunction

destabilization(societies & economies)

deficiency of resources

climate change

„water“ plays an overarching role

preservating ecosystem function

stabilizing - societies - economies

securing supply of food - water - health

mitigating climate impacts

water resources management – build-up of urban water infra-structure

our current approach: copied from ancient Romans

water is used just once

our current approach: upgraded during the past 150 years

in-appropriatewhen water is scarce

WWtreatment

pumps waterwork

sewer pipes

the smart way of using water

applying

innovative technology

for

converting wastewater into water ready for use

notice:

wastewater is a resource

urban water reuse

urban water reuse

goal: • minimization of water abstraction from natural resources

• minimization of costs for sewer installation

• minimization of time for installation

targets: • peri-urban agriculture - parks - gardens

• housing areas• high-rise buildings• hotel complexes• enterprises

- not yet properly served- in water stressed areas

roof-top hydroponics using customized recycling water

• yield: 22 t/year of leafy vegetables

• installation costs: ca. 30,000 Euro (olympic swiming pool size)

growth of leafy vegetables for direct human consumptionby spraying treated wastewater to the roots

result: - reduced fresh water abstraction

- reduced demand of land for agriculture

- reduced need for transportation (water, food)

Changi General Hospital – Dr. Chow

solution for a housing area

water purification underneath a court yard

purified water for• toilet flushing

• cleaning• landscape irrigation

steep gravity sewer:

low demand offlushing water purification

plant

Abwasser

airplane shower

allow passengers to shower

with 15 liters of water only

applicable also for commercial laundries

Urban Sustainability Centre - London

Siemens AG

Forum and Exhibition Hall

Themes:• decentralized energy generation• e-mobility infrastructure• decentralized water treatment and reuse• tele-communication

dezentralization requires central monitoring & control

DeSa/R: Decentralized Sanitation and Reuse

summary

solution of the big 4 global challengesrequires concerted action

smart use of watermakes the trick

• water reuse is an option to be considered when water is scarce

• helps satisfying the needs of people, industry and ecology alike

water reuse in urban areas (not yet served)requires decentralization of water purification technology

technology of decentralized water managementrequires participation, innovation, demonstration and proper regulation

participation

end-user

• regulators

• teachers

• city planers

• architects

• engineers

• operators

• scientists