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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Draft – do not quote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
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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
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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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