Building Preliminary Accounts

with Actual Data : Water Asset Account

Regional Training Workshop on the System

of Environmental-Economic Accounting

with a Focus on Water Accounting

September 26-30, 2016

Putrajaya, Malaysia

François Soulard Ph.D.

Environment, Energy and Transportation Statistics Division

Statistics Canada

1

Outline of presentation

1. Background information

2. First attempts at water asset accounting

3. Water yield model

4. Water yield analysis

5. Other related water assets data

2

Background

1. Work on material flows at StatCan dates back

to the 1970s (focus was on energy)

2. 1991 Green Plan included funding for the

development of the Canadian System of

Environmental and Resource Accounts

(CSERA)

3. Accounts for energy and emissions were first

published in 1993

4. Concept, sources and methods documents

published in 1997

3

Water accounting timeline

1993 2003 2005 2007 2012

SNA ‘93: Satellite accounts for the environment

System of Environmental-Economic Accounting (SEEA, draft)

Millennium Ecosystem Assessment

SEEA-Water as a statistical standard

SEEA-Central Framework as a standard

SEEA Experimental Ecosystem Accounting

HAE MEGS

1997 2010 2011 2014 2015

Econnections: Linking the Environment and the Economy

Canadian Environmental Sustainability Indicators

HAE Economy and the Environment

HAE Freshwater Supply and Demand

2013

Framework for Environmental Statistics

HAE EEA

2005

Framework funding

2016

HAE EEA-W

4

Environment Accounts and Statistics

Environmental accounts• Stock and flows

• Physical and monetary

• Land, minerals, timber, energy, GHG, water

Environmental surveys• 8 surveys, including water surveys (covering manufacturing, mining,

thermal-electric, agricultural, drinking water plants, households).

Spatial data infrastructure• Standardized boundaries (Census, Ecozones, Drainage Areas), spatial

data sets.

Publications• HAE, EnviroStats, Survey Reports, technical reports, CANSIM, PUMF,

Special Tabulations, etc.

5

- First attempt at

water asset

accounting in

Canada

- No official

statistics were

derived, but allowed

identification of the

path forward.

6

Experimental asset account, 2003

Draft – do not quote

40 655

28%

7

Basin-based water balance equation

Water Asset Account = CWB - SWB - EWB

CWB = precipitation - evapotranspiration

SWB = surface (inflow - outflow)

EWB = economic consumption (intake - discharge)

CWB: Climatic Water Balance

SWB: Surface Water Balance

EWB: Economic Water Balance (Municipal, Institutional, Commercial,

Industrial)

8

Water balance

Precipitation

- Evapotranspiration

- Storage

= Run-off R = P - ET - S

9

Run off = flows to lakes, rivers, reservoirs, base flow

Storage = flows to groundwater aquifers, consumption

10

Setting data priorities

Average Annual Streamflow for Large Rivers by Drainage Basin

Major Drainage basin

m3 per second km3 per year

Pacific Ocean 24100.00 760.02

Arctic Ocean 16400.00 517.19

Hudson Bay 30900.00 974.46

Atlantic Ocean 33400.00 1053.30

Gulf of Mexico 25.00 0.79

Canada 104825.00 3305.76

Average annual streamflow

11

Canadian Climatic Water balance

R = P – ET – S

S = P – ET – R

S = 3158 Km3 -R

S = 3158 Km3 - 3306 Km3

S = -148 KM3, or 5% of CWB

12

Strategic accounting investments

Given geographical conditions in Canada

• Large landmass, complex hydrography, varied

hydrologic regimes, overall large amount of

precipitation, accumulated stocks of non-renewable

water, etc.

• Low population density, concentrated populations,

importance of hydroelectricity, reliance of agriculture

It was decided to initiate the water accounts with

1. Renewable water assets portion of Water Assets

2. Water intake portion of MEFA

13

Renewable water assets

a.k.a. water yield

1. Develop a methodology to generate estimates of

renewable freshwater (water yield) for Canada and

regions

2. Provide a denominator against which compare water

intake data

3. Track change over time and space in the amount of

water being renewed by nature.

14

Water yield definition

Water yield is the amount of freshwater derived

from unregulated flow (m3/s) measurements

for a given geographic area over a defined

period of time.

• only measurements exhibiting unregulated flow

(that is not dammed or diverted) are used in its

computation.

• unregulated flow is a combination of baseflow,

interflow and overland flow originating from

groundwater, precipitation and/or snowpack.

15

16

Statistics Canada water yielddefined as, “the amount of freshwater derived from unregulated flow (m3 s-1)

measurements for a given geographic area over a defined period of time” and that “… is generated from a combination of baseflow, interflow and overland flow originating from groundwater, precipitation and/or snowpack”

Interflow

Baseflow

Evaporation

Runoff

Precipitation

Unregulated flow

Groundwater flow

Infiltration

Measurement

Evapotranspiration

Overview of methodology

Filter HYDAT streamflow data

Generate basin centroids

Derive monthly runoff values Develop monthly semi-variograms

17

Overview of methodology

Interpolate monthly surfaces Summarize to generate outputs

18

14 02/10/2016

Estimated vs observed

0

500

1000

1500

2000

2500

3000

197

1

197

3

197

5

197

7

197

9

198

1

198

3

198

5

198

7

198

9

199

1

199

3

199

5

199

7

199

9

200

1

200

3

m3/s

02UC002

Observed Estimated

NS: 0.871

20

0

50

100

150

200

250

300

350

197

1

197

3

197

5

197

7

197

9

198

1

198

3

198

5

198

7

198

9

199

1

199

3

199

5

199

7

199

9

200

1

200

3

m3/s

08KG001

Observed Estimated

NS : 0.833

Estimated vs observed

21

-50

50

150

250

350

450

550

650

1 11 21 31 41 51 61 71 81 91

iteration number

cubic kilometres (km3)

British Columbia Prairies

Central and Atlantic North

Stability assessment

model run 100 times with random 10% hold out

2222

Sampling statistics

Average area per station

(12 Month moving average)km2

0

2000

4000

6000

8000

10000

12000

14000

16000

18000

20000

19

71 0

1

09

05

19

73 0

1

09

05

19

75 0

1

09

05

19

77 0

1

09

05

19

79 0

1

09

05

19

81 0

1

09

05

19

83 0

1

09

05

19

85 0

1

09

05

19

87 0

1

09

05

19

89 0

1

09

05

19

91 0

1

09

05

19

93 0

1

09

05

19

95 0

1

09

05

19

97 0

1

09

05

19

99 0

1

09

05

20

01 0

1

09

05

20

03 0

1

09

05

Columbia Published trends (avg of 6 in HAE) North Saskatchewan

23

Sampling statistics

Percentage of stations reporting of maximum

(12 Month moving average)

0

10

20

30

40

50

60

70

80

90

19

71

19

72

19

73

19

74

19

75

19

76

19

77

19

78

19

79

19

80

19

81

19

82

19

83

19

84

19

85

19

86

19

87

19

88

19

89

19

90

19

91

19

92

19

93

19

94

19

95

19

96

19

97

19

98

19

99

20

00

20

01

20

02

20

03

20

04

Columbia North Saskatchewan Published trends (avg of 6 in HAE)

Percent

24

Average annual

yield = 3472 km3

Distributed unevenly

across Canada

Average annual runoff (1971-2004)

25

26 02/10/2016

98% of Canadians live in

southern Canada

Only 38% of the water

yield is in southern

Canada

27

28

29

Trends in water yield for Southern

Canada, 1971-2004

8.5% decrease from 1971-2004

30

31

Trends in water yield for the Prairies,

1971-2004

• Water yield decreased by 0.56 km3/yr

• Prairies showed highest variability

Water yield variability in the

Prairies

32

28

34

Water supply and demand: August 2005

34

Other water asset work includes…

35

Average area covered by total (all) sea ice during summer

36

Total water requirements for agricultural

production in Canada

37

Other water accounting work:

Water use to satisfy final demand, 2005

38

…excluding Hydro

…including Hydro

39

Building Preliminary Accounts

with Actual Data : Water Asset Account

Regional Training Workshop on the System

of Environmental-Economic Accounting

with a Focus on Water Accounting

Thank You for your attention

September 26-30, 2016

Putrajaya, Malaysia

François Soulard Ph.D.

Environment, Energy and Transportation Statistics Division

Statistics Canada

40

Back

41

42

•Rivers: 2,000,000 kilometres

•Lakes: 100,000 kilometres2

•Annual flow: 3,200 kilometers3

Scale: 1:1000000

Canadian Digital Drainage Area Framework,

Canada’s hydrology:

Back

43

Canadian Climate Database

44

Main Issues with Precipitation Data

Known inhomogeneities

• Change of site location

• Change of observing procedure

• Instrument deficiencies

Measurement errors

• Trace elements (ex.: dew)

• Undercatch (ex.: wind)

• Viscosity (ex.: emptying rain gauge)

• Precipitation density (ex.: snow measurement)

Varying density of station network

45

Correction to original data

3D linear regression scatter

3D non-linear spline fit

2D scatter

(MM)

46

1961-1990 Normal precipitation points

47

1961-1990 Normal precipitation surface

Back

48

Estimating Evaporation

49

Lake evaporation

Back

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