Part IA comprehensive introduction to water

footprint accountingThis is a summary of the Water Footprint

Assessment Manual Earthscan 2011by Maite Martínez Aldaya

Strengthening National Capacities for Sustainable Resource Management in Latin America and the

Caribbean CILCA 2011

COATZACOALCOS, Mexico April 7th, 2011

The water footprint concept

► The WF is an indicator of water use that looks at both direct and indirect water use of a consumer or producer.

► measured in terms of water volumes consumed (evaporated or otherwise not returned) or polluted per unit of time.

► geographically and temporally explicit indicator.

► can be calculated for a process, a product, a consumer, group of consumers (e.g. municipality, province, state or nation) or a producer (e.g. a public organization, private enterprise).

[Hoekstra et al., 2011]

Direct water footprint Indirect water footprint

Green water footprint Green water footprint

Blue water footprint Blue water footprint

Grey water footprint Grey water footprint

Water

consumption

Water

pollution

[Hoekstra et al., 2011]

Return flow

Water withdrawal

The traditionalstatistics

on water use

The water footprint components

Water footprint sustainability assessment

Water footprint accounting

Water footprint response

formulation

Setting goalsand scope

Phase 1 Phase 2 Phase 3 Phase 4

[Hoekstra et al., 2011]

Water footprint assessment

Water footprint unit

• WF of a process: water volume per unit of time.When divided over the quantity of product that results from the process, it can also be expressed as water volume per product unit.

• WF of a product: water volume per product unit. Examples:

o water volume per unit of mass

o water volume per unit of money

o water volume per piece

o water volume per unit of energy (food products, fuels)

• WF of a consumer or business and WF within an area: water volume per unit of time. The water footprint of a community of consumers can also be expressed in terms of water volume per unit of time per capita.

[Hoekstra et al., 2011]

The water footprintof a product

► the volume of fresh water used to produce the product, summed over the various steps of the production chain.

► when and where the water was used:a water footprint includes a temporal and spatial dimension.

Water footprint of a product

[Hoekstra et al., 2011]

Green water footprint

► volume of rainwater evaporated or incorporated into product.

Blue water footprint

► volume of surface or groundwater evaporated, incorporated into product or returned to other catchment or the sea.

Grey water footprint

► volume of polluted water.

[Hoekstra et al., 2011]

Water footprint of a product

Grey water footprint

• volume of polluted freshwater that associates with the production of a product in its full supply-chain.

• calculated as the volume of water that is required to assimilate pollutants based on ambient water quality standards.

[Hoekstra et al., 2011]

Water footprint of products

1 kg wheat 1 m3 water

1 kg rice 3 m3 water

1 kg milk 1 m3 water

1 kg cheese 5 m3 water

1 kg pork 5 m3 water

1 kg beef 15 m3 water

global averages

[Hoekstra & Chapagain, 2008]

[Hoekstra & Chapagain, 2008]

Food► 1300 kg of grains

(wheat, oats, barley, corn, dry peas, soybean, etc)► 7200 kg of roughages

(pasture, dry hay, silage, etc)

Water► 24000 litres for drinking► 7000 litres for servicing.

The water footprint of a cow

99%

1%

[Hoekstra & Chapagain, 2008]

Water footprintof a consumer

► the total volume of water appropriated for the production of the goods and services consumed.

► equal to the sum of the water footprints of all goods and services consumed.

► dimensions of a water footprint• volume• where and when• type of water use: green, blue, grey

Water footprint of a consumer

[Hoekstra et al., 2011]

Indirect WF Direct WF

bluewateruse

greywater

Farmer RetailerFood

processer

Virtualwaterflow

Virtualwaterflow

Virtualwaterflow

greenandbluewateruse

bluewateruse

greywater

greywater

Consumer

bluewateruse

greywater

[Hoekstra et al., 2011]

Water footprint of a consumer

► total amount of water that is used to produce the goods and services consumed by the inhabitants of the nation.

► two components:• internal water footprint – inside the country.• external water footprint – in other countries.

► water footprint of national consumption =water footprint within the nation + virtual water import

– virtual water export

Water footprint of national consumption

[Hoekstra et al., 2011]

Consumption

ExportP

rodu

ctio

n

Impo

rt

Internalwater

footprint

External water

footprint

WF of national

consumpt.

Water usefor export

Virtual water import for re-

export

Virtualwaterexport

+

+

=

=

WFwithinnation

Virtualwaterimport

++

= =

Virtual water

budget

+

+ =

=

The traditionalstatistics on

water use, butthen limited towithdrawals

[Hoekstra et al., 2011]

National water use accounting framework

International virtual water flows

Virtual water flow (m3/yr) = Trade volume (ton/yr) Product water footprint (m3/ton)

Global trade data: UN Statistics Division, New York FAOSTAT, FAO, Rome

Volume

(billion m3/yr)

Percentage

(%)

Crops and crop products

Livestock and livestock products

Industrial products

987

276

362

61

17

22

Total 1625 100

= 16% of global water use! [Hoekstra & Chapagain, 2008]

International virtual water flows (1997-2001)

Net virtual water import (Gm3/yr)-100 - -50-50 - -25-25 - -10-10 - -5-5 - 00 - 55 - 2525 - 5050 - 100No Data

National virtual water balances

[Hoekstra & Chapagain, 2008]

WFP(m3/cap/yr)600 - 800800 - 10001000 - 12001200 - 13001300 - 15001500 - 18001800 - 21002100 - 2500No Data

Water footprint per capita

[Hoekstra & Chapagain, 2008]

0

500

1000

1500

2000

2500

3000

Chi

na

Indi

a

Japa

n

Pak

ista

n

Indo

nesi

a

Bra

zil

Mex

ico

Rus

sia

Nig

eria

Thai

land

Italy

US

A

Wat

er fo

otpr

int (

m3/c

ap/y

r)

Domestic water consumption Industrial goods Agricultural goods

Water footprint per capita

Global average water footprint

[Hoekstra & Chapagain, 2008]

Global water footprintcontribution by consumption category

Global water footprint = 7450 Gm3/yr

85.8%

4.6%

9.6%

Water footprint related to consumption of industrial goods

Water footprint related to domestic water consumption

Water footprint related to consumption of agricultural goods

[Hoekstra & Chapagain, 2008]

1. Consumption characteristics

- Consumption volume

- Consumption pattern

2. Production circumstances

- Climate: evaporative demand at place of production

- Agricultural practice: water use efficiency

Major determinants of the WF

[Hoekstra & Chapagain, 2008]

The water footprint of a business

Water footprint of a retailer

bluewateruse

greywater

Farmer RetailerFood

processer

Virtualwaterflow

Virtualwaterflow

Virtualwaterflow

greenandbluewateruse

bluewateruse

greywater

greywater

Supply chain WF Operational WF

Consumer

bluewateruse

greywater

End-use WF of a product

The traditional statisticson corporate water use

[Hoekstra et al., 2011]

bluewateruse

greywater

Farmer RetailerFood

processer

Virtualwaterflow

Virtualwaterflow

Virtualwaterflow

greenandbluewateruse

bluewateruse

greywater

greywater

Supply chain WF Operational WF

Consumer

bluewateruse

greywater

End-use WF of a product

The traditional statisticson corporate water use

Water footprint of a food processor

[Hoekstra et al., 2011]

The Analysis of the Tomato Footprint, Spain

Daniel Chico, Maite Aldaya, Alberto Garrido, Gloria Salmoral and Ramon

Llamas

Chapagain, A. K. and Orr, S. (2009) “An improved water footprint methodology linking global consumption to local water resources: A case of Spanish tomatoes” Journal of Environmental Management, 90.

Chico, D., Salmoral, G., Llamas, M.R., Garrido, A. and Aldaya, M.M. (2010) "The Water Footprint and virtual water exports of Spanish Tomatoes" Papeles del Agua Virtual n.º 8, Fundación Botín, 60 p. ISBN 978-84-96655-80-05 http://www.rac.es/2/2_ficha.php?id=119&idN3=6&idN4=40

A comparison of:

Percentage variationOpen-air systems Covered systems

m3/t Green Blue Green Blue

Almería 110 158 0 181Granada 35 92 0 212Málaga 45 144 0 206Cádiz 38 109 0 165Murcia 59 191 0 188Tarragona 32 323 0 299Barcelona 35 323 0 335Gerona 144 519 0 509Lérida 81 238 0 167Guadalajara 83 379 0  Cuenca 38 662 0  Toledo 41 147 0  ciudad Real 58 268 0  Badajoz 35 151 0 0Cáceres 43 174 0 0Pamplona 21 361 0 415Santa Cruz de Tenerife 50 62 0 86Gran Canaria 109 107 0 118

58.7 244.9 0.0 205.8

Percentual comparison of WF (m3/t) for green and blue water content in open-air irrigated and covered

systems

Smaller in green water for open-air systems as in Chapagain and Orr (average 60%)

Double blue water content both in open-air irrigated and covered systems

These differences may be due to the

different data and assumptions, specially concerning irrigation schedule modelling.

Results Chapagain & Orr

Results Chico et al.

X 100

Percentual comparison of WF of production for selected regions and national average (1,000 m3/year) for green, blue and grey water

Percentage variation

1.000 m3/year Green Blue Grey

Andalucía 3 20 345Murcia 23 201 3551Cataluña 9 55 715Castilla - La- Mancha

11 53 484

Extremadura 18 71 575Navarra 23 400 2845Canarias 3 35 641otros 24 56 743Total 15 61 789

Significant differences by taking into account the yearly productions and not averages

Much smaller green water, as well as blue water (with exceptions)

Grey water footprint whole different results

Results Chapagain & Orr

Results Chico et al.

X 100

Approach through Temporal analysis

Increasing trend in WF associated to the increase in the tomato production

Green, Blue and Grey WF in absolute terms (hm3), national production and virtual water exported (hm3)

Advanced WF Economic analysis at current technology and market standpoint

National Water apparent productivity (WAP, €/m3) per production system

Rainfed Irrigated open-air GreenhousesShare of National production (in tons) 0.003 0.6 0.4Av. Water Apparent productivity (€/m3) 2.10 3.08 7.78

Conclusions

•The estimations on consumptive use of water for crops have usually a potential significant error

•The analysis of the economic water productivity is very important from the practical point of view

•The results obtained for the water apparent productivity vary significantly between years, although the greenhouse production shows a significantly higher productivity than irrigated open-air and rainfed production

3

SourcesHoekstra, A.Y. and Chapagain, A.K. (2008) Globalization of water: Sharing the planet's freshwater

resources, Blackwell Publishing, Oxford, UK. Hoekstra, A.Y., Chapagain, A.K., Aldaya, M.M. and Mekonnen, M.M. (2011) The water footprint

assessment manual: Setting the global standard, Earthscan, London, UK. Available from: http://www.waterfootprint.org/downloads/TheWaterFootprintAssessmentManual.pdf

Morrison, J., Morikawa, M., Murphy, M. and Schulte, P. (2009) Water scarcity and climate change: Growing risks for businesses and investors. Ceres, Pacific Institute. Available from: http://www.ceres.org/Document.Doc?id=406

WFN (2011) Water Footprint Network. Available from: http://www.waterfootprint.org

Gracias !