quality accounts. outline why quality accountswhy quality accounts structure of quality...

Quality Accounts

OutlineWhy Quality AccountsStructure of Quality AccountsAquifersRiversHow to define quality classes?Several country examplesIssuesAggregationMeasurement

Why quality accounts?Quality accounts describe the quality of water resources at the beginning and end of the accounting period in terms of chemical, physical and biological characteristicsImportant becauseQuality limits water availability for certain purposesIt is a first step towards ecosystem accounting and its variantsBUT Still experimental (few country experiences; little or no standardization)Link with pressures due to human activities is not direct

Quality of what?Quality of water bodies, NOT waterbeds / riparian zoneWater body : mass of water distinct from other masses of waterExamples: rivers, lakes, aquifers

Structure of quality accountsSource: SEEAW

Aquifers: AustraliaSource: Water Account for Australia 1993-94 to 1996-97 - Australian Bureau of Statistics, May 2000.Groundwater quality in Victorian provinces (in million m3)Based on sustainable yield as a proxy, NOT volume of storage

Rivers: from point to monitoringAre these statistics relevant?

Rivers Monitoring of points & generalisation to water systems Particular difficulty with water courses: how to account for their relative size? Runoff is measured at the lowest point of a basin the quality varies along the stream The mere length confuses large rivers and small streams Statistics of points make sense only when the monitoring system is dense rarely the case

Stretches / ReachesReach or stretch: a portion of a stream or river, as from one turn to another, supposedly having constant characteristics any distance between 2 monitoring points

Accounting unit: SRU (1)River reaches as basic accounting units for riversImportance is best measured by length and dischargeBest candidate is SRU (standard river unit) = reach length discharge in m3 s-1Large and small rivers can be aggregated when measured in SRUs

Can be classified or weighted with quality indexesResults comparables from basin to basinRobust and easy to compute

Accounting Unit: SRU (2)X Fast, smallSlow, mediumLarge riverQiQjQkLiXXLkLj= a SRU= b SRU= c SRUFlowLength

SummaryFor compiling quality accounts we need: SRU value for each river reach for all riversWe need to assign a quality for each reach for all rivers

Accounting Unit: SRU (2)X Fast, smallSlow, mediumLarge riverQiQjQkLiXXLkLj= 4 SRU Q1= 0.5 SRUQ2= 1.5 SRU Q2FlowLength

Structure of quality accountsSource: SEEAW

Ways of assessing water qualityAccording to disturbances/perturbations to functionsTotal hydraulic and osmotic power of river basinsHealth of ecosystem approach (resilience)

Defining quality classesNormative values for determinands (parameters)Physical: temperature, colourChemical: pH, NH4+ Biological: bacteria, flora, fish Etc..Allowable deviations from reference conditionsEuropean Water Framework Directive

Example: Malaysia (1)WQI = 0.22*SI DO + 0.19*SI BOD + 0.16*SI COD + 0.15*SI AN + 0.16*SI SS + 0.12*SI pH

whereSI is the subindex of each parameter. DO - Dissolved Oxygen BOD - Biological Oxygen Demand COD - Chemical Oxygen Demand AN - Ammoniacal Nitrogen SS - Suspended Solid pH - Acidity/Alkalinity

Example: Malaysia (2)

Usage102030405060708090100WQIGeneralVery PollutedSlightly PollutedCleanWater ClassVIVIIIIIIPublic Water SupplyNot AcceptableDoubtfulNecessary Treatment Becoming more ExpensiveMinor Purific RequiredPurification not NecessaryRecreationNot AcceptableObvious Pollution AppearingOnly for BoatingDoubtful for Water ContactBecoming Polluted Still Acceptable Need Bacteria CountAcceptable for all SportsFish, Shellfish and WildlifeNot AcceptableCoarse Fish OnlyHandy Fish OnlyDoubtful for Sensitive FishMarginal for TroutAcceptable for all FishNavigationNot AcceptableObvious Pollution AppearingAcceptableTreated water TransportationNot AcceptableAcceptable102030405060708090100WQI

Example: France (1)SEQ-eauUse-orientedRecognizes: drinking water, leisure, irrigation, livestock watering, aquaculture aquatic lifeBased on 15 suitability indicatorsComputed from 135 determinantsMatrices: determinants X indicators (computed from) uses X indicators (significant for) determinants X classes (threshold values)Source: Presentation User-Producer Conference by R. Lalement

Example: France (2)

Example: France (3)

Example: France (4)Results in a class of suitability for each use an index (and class) for overall quality

For each indicator, the worst determinant winsFor each use, the worst indicator winsFor each determinant, apply the percentile 90 rule to multiple samples (not the average)[this is called Rule of the worst]... an in depth assessment for uses, but little ecology : independent of ecotype

France: Monitoring Costs (5)The estimated cost of the surveillance monitoring programme is

77 M for rivers and 8M for lakes

for a management plan, or

50 k for rivers 40 k for lakes

per site for a management plan, or

150 /km2 (rivers and lakes), or 150 /km (rivers).

Example: CanadaS = scope, number of failed determinands/totalF = frequency, number of failed tests/totalE = excursion, target value/observed value

Results: French Quality AccountsExample:France 1992-1994Results: organic matter indicator in SRU*1000

River size class

State 1992

Change 1994-1992

State 1994

Adjustment

1A

1B

2

3

HC

1A

1B

2

3

HC

1A

1B

2

3

HC

1A

1B

2

3

HC

Main rivers

5

1253

891

510

177

3

329

2

-152

-165

8

1583

893

358

12

0

6

7

-32

0

Main tributaries

309

1228

1194

336

50

16

464

-275

-182

-22

325

1691

919

154

28

0

0

0

0

0

Rivers

260

615

451

128

47

46

134

-129

-17

-28

306

749

322

110

18

-1

-4

0

0

0

Brooks

860

1464

690

243

95

-51

-170

227

15

-23

810

1295

917

258

72

7

-6

1

0

0

ISSUESChoice of determinandsClassification of usesAssessment: Rule of worstTemporal issuesAggregation over space (indicators)Link with economic sphere

Choice of determinandsCountry and context dependentBased on functions or uses

Determinand groupNumber of determinandsTotalof which: Specific to Canadaof which: Specific to Franceof which: Specific to South Africaof which: Common determinandsEnvironmental101116Gases dissolved5211Metals (and metalloids)243219Nutrients5111Pesticides68222364Radioactivity2626Salinity14134Toxics (n-metal, n-pesticides)104363832

Classification of usesNo standardized classification of uses or functionsDifferent uses for different type of water bodies? (case of France)Different uses per water body? (USA)How to deal with multiple use?Choose the most stringent use? (AUS)

Assessment : Rule of the worstOne out, all outReason: assure equal weight to all parametersApplicable at level of determinands, indicators or usesProblem:Extreme values; seasonal variationsImprovement of monitoring leads to increased probability of finding bad status

Rule of the worst: Application

Canal

Reach"2005""2006"RofW_05QC 05RofW_06QC_06SRU1SRU2

Det 1Det 2QDet 1Det 2Q

Station

125601220606020121603500500

225606020606020603603500500

325606020606020603603500500

425606020606020603603500500

QC1QC2QC3QC4QC5

Opening stocks5000150000

Closing stocks00200000

Changes in stocks-500050000

River

Reach"2005""2006"30-Jun30-SepRofW_05QC 05RofW_06QC_06RofW_totQuality classSRU1SRU2SRU3SRU490PMedianModeMean

Det 1Det 2Det 3QDet 1Det 2Det 3QDet 1Det 2Det 3QDet 1Det 2Det 3Q

Station

1103030305606060106060602060606020302603302501002002003052.5

22030303076060601460606020606060203026033021402804004003052.5

32530303066060601260606020606060203026033021503005005003052.5

450303030126060602460606020606060203026033026001200100010003052.5

513303030156060603060606020606060203026033021953902602603052.5

6493030301760606034606060206060602030260330283316669809803052.5

7873030301960606038606060206060602030260330216533306174017403052.5

8463030302060606040606060206060602030260330292018409209203052.5

9253030302160606042606060206060602030260330252510505005003052.5

10303030302460606048606060206060602030260330272014406006003052.5

QC1QC2QC3QC4QC5TOTALGlobal Quality Index



Changes in stocks0-578611572005786

SelectionRules

160

258

378

414

556

667

739

865

966

1087

1145

1255

1312

1467

1568

1677

Average57.125

Mode67

Median62.5

P9026.5

P8043.8

Pctrank 600.948

RofW12

Sheet1

Reach"2005""2006"30-Jun30-SepRofW_05QC 05RofW_06QC_06RofW_totQuality classSRU1SRU2SRU3SRU490PMedianModeMean

Det 1Det 2Det 3QDet 1Det 2Det 3QDet 1Det 2Det 3QDet 1Det 2Det 3Q

Station

125603860206060602060606020606060203826033825005005005006058.1666666667

225606060206060602060606020606060206036036035005005005006060

325606060206060602060606020606060206036036035005005005006060

425606060206060602060606020606060206036036035005005005006060

525606060206060602060606020606060206036036035005005005006060

625606060206060602060606020606060206036036035005005005006060

725606060206060602060606020606060206036036035005005005006060

825606060206060602060606020606060206036036035005005005006060

925606060206060602060606020606060206036036035005005005006060

1025606060206060602060606020606060206036036035005005005006060

1125606060206060602060606020606060206036036035005005005006060

1225606060206060602060606020606060206036036035005005005006060

1325606060206060602060606020606060206036036035005005005006060

1425606060206060602060606020606060206036036035005005005006060

1525606060206060602060606020606060206036036035005005005006060

1625606060206060602060606020606060206036036035005005005006060

1725606060206060602060606020606060206036036035005005005006060

1825606060206060602060606020606060206036036035005005005006060

1925606060206060602060606020606060206036036035005005005006060

2025606060206060602060606020606060206036036035005005005006060

QC1QC2QC3QC4QC5




Seasonal

Reach31-Dec31-Mar30-Jun30-SepRofW_05QC 05RofW_06QC_06RofW_05QC 05RofW_05QC 05SRU1SRU2SRU3SRU4RofW_totALTERNATIVESQuality class

Det 1Det 2Det 3QDet 1Det 2Det 3QDet 1Det 2Det 3QDet 1Det 2Det 3Q90PMedianModeMean

Station

125606767201660602060606020606060206031616036035005005005001660606057.51

2256060602060606020606060206060602060360360360350050050050060606060603

3256060602060606020606060206060602060360360360350050050050060606060603

4256060602060606020606060206060602060360360360350050050050060606060603

5256060602060606020606060206060602060360360360350050050050060606060603

6256060602060606020606060206060602060360360360350050050050060606060603

7256060602060606020606060206060602060360360360350050050050060606060603

8256060602060606020606060206060602060360360360350050050050060606060603

9256060602060606020606060206060602060360360360350050050050060606060603

10256060602060606020606060206060602060360360360350050050050060606060603

11256060602060606020606060206060602060360360360350050050050060606060603

12256060602060606020606060206060602060360360360350050050050060606060603

13256060602060606020606060206060602060360360360350050050050060606060603

14256060602060606020606060206060602060360360360350050050050060606060603

15256060602060606020606060206060602060360360360350050050050060606060603

16256060602060606020606060206060602060360360360350050050050060606060603

17256060602060606020606060206060602060360360360350050050050060606060603

18256060602060606020606060206060602060360360360350050050050060606060603

19256060602060606020606060206060602060360360360350050050050060606060603

20256060602060606020606060206060602060360360360350050050050060606060603

QC1QC2QC3QC4QC5




Aggregation: space (1)Which rivers to include?Scale determines outcomeRiver basinWeighted average indicatorHotspotsPattern index

Aggregation: space (2) River Quality Global Index (RQGI) Aggregates over river basin Weighted average of SRU according to quality class Scale 0-10 n is number of classes

Aggregation: space (3)Pattern indexMeasures the variability in space in quality of the River BasinAble to distinguish hotspots

Temporal issuesHow to reflect seasonal variations in the quality accounts?What to do with inter-annual variations (wet years..)Actual SRU or averages?How to deal with sudden eventsFrequency of monitoring

SEEAW advocates compilation of Quarterly Accounts

Link with economic sphere (1)Water quality accountsIdeal is to measure efficiency of water quality management programmes at basin levelBUT: changes in water quality can have different causes

Water quality t1 = f(Water quality t0, (uncontrolled events), (abstractions), (emissions), (expenditure))

f() = unknownTherefore.

Link with economic sphere (2)

QC1QC2-QCnTotalOpening stockChanges due to economic causesDischarge of waste waterAbstractionReturnsChanges due to natural causes

accidentsClosing stock

QuestionsData availability? Frequency?Distribution of monitoring stations?Are flows and quality measured simultaneously?Which determinands are measured?Economic data per river basin?Are different uses distinguished?Experience in compilation?

Refer to document unceea/1/12The S&C will be sent to statistical office through mail, email, fax, internetThe questionnaire will cover a general part of the compilation of environmental accounts and a module specific one covering: MFA, resource specific accounts (water, mineral and energy, forest, fisheries, land, waste,Refer to document unceea/1/12The S&C will be sent to statistical office through mail, email, fax, internetThe questionnaire will cover a general part of the compilation of environmental accounts and a module specific one covering: MFA, resource specific accounts (water, mineral and energy, forest, fisheries, land, waste,