canadian water quality ccme water guidelines for the

Canadian Environmental Quality GuidelinesCanadian Council of Ministers of the Environment, 2001

Acknowledgements

The report was authored by the Water Quality IndexTechnical Subcommittee:

Bernie Neary, Ontario Ministry of the EnvironmentKevin Cash, Environment CanadaSerge Hébert, Québec Ministère de l'Environnement etde la FauneHaseen Khan, Newfoundland Department ofEnvironment and LabourKaren Saffran, Alberta EnvironmentLes Swain, British Columbia Ministry of Environment,Lands and ParksDwight Williamson, Manitoba EnvironmentRalph Wright

In addition to the authors of the report, there wereseveral other people who contributed significantly to thedevelopment of the index. Dr. W. Hart, Centre forWater Resources, Memorial University, performeddetailed evaluations of earlier index formulations.Ashok Lumb (Environment Canada), Earle Baddaloo(Alberta Environmental Protection), Jackie Shaw(Alberta Environmental Protection), Anne Kerr(Environment Canada), Kim Hallard (SaskatchewanEnvironment and Resource Management), MurrayHilderman (Saskatchewan Environment and ResourceManagement), Peter Rodgers (Environment Canada) andKarl Lauten (Saskatchewan Environment and ResourceManagement) contributed to discussions of the index.Ilze Reiss and Herb Vandermeulen of EnvironmentCanada and Scott Tessier and Margaret Gibbs ofCCME provided significant assistance during the courseof the committee’s work.

Introduction

The purpose of this report is to describe thedevelopment of a CCME Water Quality Index (CCMEWQI). The CCME WQI is a tool for simplifying thereporting of water quality data. Traditional reports onwater quality trends typically consisted of variable-by-variable, water-body-by-water-body statisticalsummaries. This type of reporting is of value to waterquality experts and managers, but is often inaccessibleto non-experts. It is hoped that the CCME WQI will filla gap, providing meaningful summaries of overall waterquality and trends, while producing output that isaccessible to senior managers and non-technical laypeople.

It is important when using indices to keep in mind theirlimitations. While a stock market index is a goodindicator of the overall performance of the market,anyone with a stock portfolio will be interested in theperformance of individual stocks, or stock sectors. Anenvironmental index is similar. The CCME WQI is notintended to replace a detailed analysis of environmentalmonitoring data, nor should it be used as the only toolfor management of water bodies. What it can do isprovide a broad overview of environmentalperformance, and it was with this in mind that theCCME Water Quality Index was developed.

A number of attempts have been made to develop thistype of index 1,2,3,4. The advantages of indices includetheir ability to represent measurements of a variety ofvariables in a single number, the ability to combinevarious measurements in a variety of differentmeasurement units in a single metric, and the facilitationof communication of the results. Disadvantages includethe loss of information on single variables, thesensitivity of the results to the formulation of the index,the loss of information on interactions betweenvariables, and the lack of portability of the index todifferent ecosystem types 5.

The CCME WQI is not intended to replace a detailedassessment of water quality conditions throughconventional water quality assessment methods. Itpresupposes good analytical data on chemical waterquality measurements relevant to the site(s) beingassessed.

Background - Existing Canadian Indicesand Index Evaluations

Prior to the development of the CCME Water QualityIndex, there were a number of jurisdictions and

Canadian Water QualityGuidelines for the Protectionof Aquatic Life

CCME WATERQUALITY INDEX 1.0

Technical Report

CCME WATER QUALITY INDEX 1.0TECHNICAL REPORT

Canadian Water Quality Guidelinesfor the Protection of Aquatic Life

2

institutions in Canada using some type of metric toassess water quality. The Water Quality Index TechnicalSubcommittee was formed by the Water QualityGuidelines Committee of the Canadian Council ofMinisters of the Environment in 1997 to assess differentapproaches to index formulation and to develop anindex that could be used to simplify water qualityreporting in Canada. The different approaches in use inCanada are briefly described in this section of the report.

Centre St LaurentThe Centre St Laurent (CSL) is an Environment Canadaoffice responsible for reporting on the St. LawrenceRiver. The WQI developed at CSL was

WQI=[Σ(Ai x Fi)]/n

Where:Ai is the mean level of exceedence for variablei for guideline i. When a variable valueexceeds a guideline for that variable, the ratio“exceeding value/guideline value” iscalculated. These ratios are summed and thendivided by the number of times they occur.

Fi is the frequency of values that exceed aguideline for a variable relative to the totalnumber of values obtained for that variable (Fi

= Fexceed/Ftotal for variable i).

n is the number of variables.

The CSL calculated a number of different water qualityindices, depending on what water uses they wereconsidering. For example, separate index calculationswere made based on guidelines for protection of aquaticlife, primary contact recreation, human consumption,and for saltwater areas of the St. Lawrence estuary, forshellfish harvesting.

QuebecThe Quebec index6 was based on an approach originallydeveloped in New Zealand2 . This index was theminimum of a number of subindices, which arecalculated for each of the water quality variablesmeasured:

WQI = min(Isub1, Isub2,…,Isubn)

What made this approach different from others used inCanada was the use of ‘Delphi curves’ for the calculationof the subindices. Delphi curves are based on expertopinion as to the significance of a particular level of awater quality component. They are usually non-linear,

and represent the aggregated opinion of what a particularlevel of a particular contaminant means in terms of thedesignated water use. The Quebec index represented the‘worst case impairment’ of any of the variables measured.

British ColumbiaThe British Columbia approach to calculating a waterquality index included a factor not considered in any ofthe other indices:

WQI = (F12+F2

2+F32)½

Where:F1 is the percentage of water quality guidelinesexceeded.F2 is the percentage of measurements in whichone or more of the guidelines were exceeded.F3 is the maximum (normalized to 100) bywhich any of the guidelines were exceeded.

The British Columbia index7 had the longest and mostextensive development and application. Two of itsfactors are analogous to components of other indices: F2

is similar to the Alberta index, while F3 is similar to theCentre St Laurent index. F1 was not found in any of theother indices. British Columbia had used its index togenerate a provincial report focusing on water quality8.

As with the other jurisdictions, British Columbia uses itsindex based on a variety of objectives. Each water bodyis assessed with respect to designated uses. BritishColumbia has different objectives for drinking,recreation, irrigation, livestock watering, wildlife, andaquatic life. Separate rankings were published based oneach use relevant to the water body.

ManitobaManitoba adopted the British Columbia approach.Based on an evaluation of four years of data on eightsites in Manitoba, the province concluded that theBritish Columbia index appeared to give reasonableresults for the Manitoba case. They had not made anyattempts to modify the index. Manitoba used the indexfor their state of the environment report9.

AlbertaAlberta used a ‘performance indicator’ for water qualityin their state of the environment reporting. Theirindicator for water quality was:

A = (nexceed/nmeasure)*100

This was the percentage of the samples taken at a sitewhere one or more of the variables exceed the objectives



3

for a designated use. Common uses in Alberta includerecreation, agriculture, and aquatic life.

OntarioOntario had made an evaluation of the British Columbiaindex, but had modified F3 so that it represented theaverage normalized exceedence rather than themaximum. They had reported some problems with thethird factor of the British Columbia index saturatingwhen large exceedences of objectives occurred. Therewas no index being used routinely in Ontario.

Comparison of Indices

An analysis of the concepts behind the various indicesand performance measures revealed that while there were computational differences in the indices, many ofthem were measuring the same attributes of deviationfrom objectives.

Each of the independent index approaches was acombination of one or more measures of three attributesof water quality, measured against objectivesappropriate for the use of the water. These differentapproaches had been documented and summarised forthe CCME in 199610.

Jurisdiction or Institution Proportion of ObjectivesExceeded

Frequency with whichObjectives are Exceeded

Amplitude by whichObjectives are Exceeded

British Columbia F1 F2 F3

CSL - Fi AiAlberta - %Exc -Quebec - - DelphiEnvironment Canada - - A

CCME Water Quality Index Development

Conceptual Model for the IndexThe Water Quality Index Technical Subcommitteeadopted the conceptual model from the BritishColumbia index. The ‘Delphi’ approach used in Quebecwas seriously considered for incorporation in the index,but was discarded because of the time and logisticsinvolved in developing ‘Delphi’ curves for largenumbers of water chemistry variables.

There are three factors in the index, each of which hasbeen scaled to range between 0 and 100. Figure 1 showsthe conceptual model for the index. The values of thethree measures of variance from selected objectives forwater quality are combined to create a vector in animaginary ‘objective exceedence’ space. The length ofthe vector is then scaled to range between zero and 100,and subtracted from 100 to produce an index which is 0 orclose to 0 for very poor water quality, and close to 100 forexcellent water quality. Since the index is designed to

measure water quality, it was felt that the index shouldproduce higher numbers for better water quality.

The Technical Subcommittee developed an earlierversion of the index based on this conceptual model.This earlier version was evaluated on synthetic datasets11, and data sets from British Columbia12, andNewfoundland13. Along with evaluations in Alberta andOntario, these evaluations revealed that significantproblems arose due to the formulations for estimatingfrequency and amplitude.

As a result of these problems, Alberta Agriculture Foodand Rural Development in association with AlbertaEnvironmental Protection funded research intoalternative formulations of the frequency and scopefactors14. The Technical Subcommittee relied heavilyon this work, and used it as the basis for the finalformulation of the CCME WQI.



4

Scope

Freq uency Amplitu

de

CCME Water Quality Index Formulation

The index consists of three factors:

Factor 1: ScopeF1 (Scope) represents the extent of water qualityguideline non-compliance over the time period ofinterest. It has been adopted directly from the BritishColumbia Index:

100variablesofnumberTotal

variablesfailedofNumber1 ×

=F

Where variables indicates those water quality variableswith objectives which were tested during the time periodfor the index calculation.

Factor 2: FrequencyF2 (Frequency) represents the percentage of individualtests that do not meet objectives (“failed tests”):

100 testsofnumber Total

testsfailed ofNumber 2 ×

=F

The formulation of this factor is drawn directly from theBritish Columbia Water Quality Index.

Factor 3: AmplitudeF3 (Amplitude) represents the amount by which failedtest values do not meet their objectives. F3 is calculatedin three steps. The formulation of the third factor isdrawn from work done under the auspices of theAlberta Agriculture, Food and Rural Development15.

(i) The number of times by which an individualconcentration is greater than (or less than, when theobjective is a minimum) the objective is termed an“excursion” and is expressed as follows. When thetest value must not exceed the objective:

1−

=

j

ii Objective

ValueFailedTestexcursion

For the cases in which the test value must not fall belowthe objective:

1−

=

i

ji ValueFailedTest

Objectiveexcursion

ii) The collective amount by which individual tests areout of compliance is calculated by summing theexcursions of individual tests from their objectivesand dividing by the total number of tests (both those

Figure 1. Conceptual Model of the Index



5

meeting objectives and those not meetingobjectives). This variable, referred to as thenormalized sum of excursions, or nse, is calculatedas:

testsof

excursion

nse

n

ii

#1

∑==

iii) F3 is then calculated by an asymptotic function thatscales the normalized sum of the excursions fromobjectives (nse) to yield a range between 0 and 100.

+=

01.001.03 nse

nseF

The CCME WQI is then calculated as:

−

7321100

.

F+F+F = CCMEWQI

32

22

12

The factor of 1.732 arises because each of the threeindividual index factors can range as high as 100. Thismeans that the vector length can reach

as a maximum. Division by 1.732 brings the vectorlength down to 100 as a maximum.

Categorization of Index Values

The assignment of CCME WQI values to categories ofwater quality is termed “categorization” and represents acritical but somewhat subjective process.Categorization should be based on the best availableinformation, expert judgement, and the general public’sexpectations of water quality. The categorizationpresented here is preliminary and will no doubt bemodified as the index is tested further.

Because of the nature of the index, it is impossible todetermine from an index range whether the ranking isdue to extreme excursions in one variable, or frequentsmall excursions in one or more variables. Theprototype Water Quality Index calculator, developedwith support from Alberta Agriculture, Food and RuralDevelopment allows users to determine the variablesprimarily responsible for the behaviour of the index.

Once the CCME WQI value has been determined, waterquality can be ranked by relating it to one of thefollowing categories:

Excellent: (CCME WQI Value 95-100) – waterquality is protected with a virtualabsence of threat or impairment;conditions very close to natural orpristine levels. These index values canonly be obtained if all measurementsare within objectives virtually all ofthe time.

Good: (CCME WQI Value 80-94) – waterquality is protected with only a minordegree of threat or impairment;conditions rarely depart from naturalor desirable levels.

Fair: (CCME WQI Value 65-79) – waterquality is usually protected butoccasionally threatened or impaired;conditions sometimes depart fromnatural or desirable levels.

Marginal: (CCME WQI Value 45-64) – waterquality is frequently threatened orimpaired; conditions often depart fromnatural or desirable levels.

Poor: (CCME WQI Value 0-44) – waterquality is almost always threatened orimpaired; conditions usually departfrom natural or desirable levels.

Index Application

The CCME WQI as described above has been applied toseveral data sets from across Canada. This section willgive some examples.

OntarioMost of Ontario’s routine water quality monitoring datacomes from an extensive network of regularly monitoredstations in the Provincial Water Quality MonitoringNetwork (PWQMN). The CCME WQI has been testedon data from over eighty of these stations, and iscurrently being run on all data in the network gatheredsince 1980. The following example focuses on eightstations from the lower Trent River Watershed insouthern Ontario (see Figure 2). The variables includedin this data set are: aluminum, arsenic, cadmium,chromium, copper, dissolved oxygen, fecal coliform,

2.17330000100100100 222 ==++



6

nickel, pH, phenols, phosphorus, and zinc. Data aretypically collected on a monthly basis.

The stations selected for these examples arerepresentative of data collected at over 800 sites inOntario between 1980 and 1995. The results are shownin Figure 3. There is good discrimination between sites

on rivers flowing from primarily Canadian Shield based,non-agricultural areas (for example, station17002100302) and sites where there are some impactsdue to livestock rearing and low-intensity agriculture(for example, Station 17002104702). A full assessmentof the utility of the index in reporting on Ontario waterquality is in preparation.

#

#

#

#

#

#

#

#17002100202

17002100302

17002100702

17002104502

17002104602

17002104702

17002105702

17002106702

Figure 2. Location of Lower Trent River PWQMN Stations (Ontario)

17002100702

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1980 1982 1984 1986 1988 1990 1992 1994

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17002105702

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17002104502

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17002104602

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17002100202

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17002104702

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17002106702

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1980 1982 1984 1986 1988 1990 1992 1994

Year

CWQI #

#

#

#

#

#

#

#

Figure 3. CCME WQI Trends in the Lower Trent River



7

NewfoundlandThe CCME WQI was applied to three selectedwatersheds in Newfoundland. Water quality data from1986 to 1994, collected under Federal-Provincial WaterQuality Agreement, for twelve stations located in theHumber Watershed, the Exploits Watershed and theQuidi Vidi Watershed were used in the analysis (seeFigure 4). Variables included in the index calculationwere conductivity, turbidity, dissolved oxygen, pH,dissolved organic carbon, aluminum, arsenic, cadmium,chromium, copper, iron, manganese, lead, nickel,

phosphorus and zinc.

The CCME WQI trend at eight of these sites is shown inFigure 5. An assessment of the application of the CCMEWQI to these watersheds15 concluded that there wasgood discrimination between pristine sites (for example,Lloyds River - YN0001) compared to sites impacted byurbanization or past mining activities (YO0017,YO0001).

Figure 4. Water Quality Index Sites in Newfoundland

!

!

!

!

!!

!

!

!!!!

YL0011

YK0022

YL0012

YR0021

YO0001YO0020

YO0107

YN0001

��

!!!!!

!!! !!!!



8

Figure 5. CCME WQI trends at selected sites in Newfoundland

Saskatchewan

The data for the Saskatchewan application wereobtained from the Prairie Provinces Water Board(PPWB). The PPWB was established in the 1930s andrepresents an agreement among the three PrairieProvinces and the Federal government. Originally, thePPWB was concerned only with water quantity(transfers across provincial boundaries) but the interestsbroadened over time and led to the inclusion of a waterquality program starting in 1968. Currently the PPWBmonitors water quality at twelve sites (six along theAlberta Saskatchewan boundary and six along theSaskatchewan-Manitoba boundary – see Figure 6).

Figure 7 shows the results when the CCME WQI isapplied to eight of these reaches. Variables included inthis example are: chloride, cooper, fecal coliform, iron,lead, manganese, NO2 + NO3, sodium, sulphate, zinc,

phosphorus, dissolved oxygen, total dissolved solids andpH. Data were typically collected on a monthly basis.

As can be seen in Figure 7 overall water quality rangesfrom marginal to excellent, depending on the river reachand sample year. As expected, the Churchill River, theleast impacted in the sampling network, consistentlyshows the highest CCME WQI values. In contrast, theCarrot River, which is subject to both agricultural andforestry activity, has a water quality which is typically“fair”, largely as a consequence of excursions to thephosphorous objective. As with a recent PPWBanalysis, the CCME WQI does not suggest a significanttrend in water quality for any of these sites. A morecomplete assessment of the CCME WQI in these riversis currently in progress.

!

!

!

!

!!

!

!

!!!!

YL0011

YK0022

YL0012

YR0021

YO0001YO0020

YO0017

YN0001

YN0001

0.0

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QI

YO0017

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QI

ZM0016

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QI

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QI

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QI

ZM0144

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1986 1988 1990 1992 1994

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QI



9

(

(

(

(

((

(

(((

(

(

(

(

(

Cold R.

Beaver R.

North Saskatchewan R.

Battle R.

Red Deer R. near Bindloss

South Saskatchewan R.

Churchill R.Wasawakasik L.

Churchill R.Island Falls

Saskatchewan R.

Carrot R.

Red Deer R.at Erwood

Assiniboine R.

Qu'Appelle R.

Figure 6. Prairie Provinces Water Board Sampling Sites

Qu'Appelle River

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QI

South Saskatchewan River

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QI

Red Deer at Bindloss

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QI

Red Deer at Erwood

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QI

North Saskatchewan River

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QI

Carrot River

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QI

Churchill River at Wasawakasik Lake

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QI

Beaver River

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QI

Figure 7. CCME WQI trends at Prairie Provinces Water Board Stations



10

AlbertaAlberta Environment maintains about twenty long-termwater quality sampling sites in the province’s majorrivers (the long-term river network, LTRN). Mostvariables are measured at these sites on a monthly basis,but some are tested quarterly. The example illustratesthe application of the CCME WQI to three sites in theBow River: at Cochrane, upstream of Calgary; atCarseland, downstream of Calgary, and at Ronalane,near the confluence with the Oldman River (see Figure8). The variables included in the calculation of theindex are: cyanide, fluoride, pH, dissolved oxygen,aluminum, arsenic, boron, cadmium, copper, nickel,lead, mercury, selenium, zinc, total phosphorus, totalnitrogen, ammonia, nitrite, and fecal coliform bacteria.Alberta is continuing to test the index and plans to revisethe list of

variables used, including the addition of pesticide data.

Of the three sites, the best quality is observed, asexpected, at the Cochrane site (see Figure 9). Theimpact of Calgary is seen at the Carseland sitedownstream of the city. The Ronalane site shows somerecovery and is somewhere between the other two inquality. The apparent improvement at the Carseland sitein the early 1980s could be interpreted as showing theeffect of wastewater treatment upgrades in Calgary in1982 (phosphorus removal). This interpretation isclouded, however, by the fact that the full suite ofvariables was not collected at this site until 1987 (seeApplying the Index).

#

#

#

Bow Riverat Cochrane

Bow Riverat Ronalane

Calgary

Bow RiverDownstreamof Carseland

Figure 8. Bow River Sites (Alberta)



11

Bow River at Cochrane

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QI

Bow River Downstream of Carseland

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Bow River at Ronalane

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QI

Figure 9. CCME WQI Trends in the Bow River (Alberta)

Discussion

The examples presented above show the capability forthe index to identify differences between sites of varyingwater quality, and identify trends in water qualityassociated with improvement or degradation of a stretchof river. A quantitative assessment of the validity of theindex was not possible, because there are no existingaccepted metrics against which to compare it.

Of the many problems inherent in the development ofthis index, two required most attention: the varying scaleof measurements, and the range of exceedence.Differing scales of measurement are characteristic ofwater quality analyses. Some parameters, such aspesticides, may be environmentally significant at ng∙L-1

ranges, while others are significant at the mg∙L-1 range.Adopting the objective-oriented approach developed inBritish Columbia allows these types of data to beassembled in the same multivariate index formulation,since the metric of interest is the comparison of themeasured data relative to its objective.

The objective-oriented BC WQI also avoided theproblem of weighting parameters. There werediscussions of how to deal with objective exceedence fora parameter such as phosphorus relative to a parameterwith more toxic associations such as PCBs. TheSubcommittee felt that since the relative toxicities ofdifferent chemicals were addressed during the



12

development of water quality objectives, furtherweighting was not warranted.

Another problem frequently encountered in reporting onwater quality data is results below the analyticaldetection limit. It is problematic to deal with thesenumbers statistically, but the problem is avoided withthe CCME WQI approach. ‘Less than’ values are usedin the index as observations which are within theobjectives, so the results are counted, but all thestatistical problems associated with how to deal withthem are circumvented.

Applying the Index

Applying this index to water quality data sets must bedone with due regard to how the index is formulated.Experience with the British Columbia index has shownthat misapplication, or use of the index for purposes forwhich it was not designed, can lead to erroneousconclusions. There are several rules for application thatshould be taken into consideration:

a) Index comparisons should only be made whenthe same sets of objectives are being applied.The CCME WQI allows the index user to select theobjective set on which to compare measured waterquality. This is a design feature that increases theversatility of the index considerably but allows formisuse. Different jurisdictions in Canada usedifferent objectives for water quality, and there areusually different objectives for different water uses.Objectives designed for the protection of water usedfor irrigation or livestock watering will be differentfrom those designed to protect sensitive aquatic life.If an index value is calculated on one set ofobjectives and compared to an index value based ona completely different set of objectives, anyconclusions drawn will be wrong.

b) Index comparisons should only be made usingthe same sets of parameters. This is commonsense “apples to apples” reasoning. Comparing asite where most of the measured parameters arepesticides to a site where most of the measuredparameters are metals will yield information oflimited value. It is possible to obtain index valuesunder these conditions, but comparison of thesetypes of sites will only tell the user how each site isdoing relative to those objectives. There is no waythe index can replace a detailed site assessment ofdifferent types of pollutants. Similarly, if a trend-through-time index series is calculated for a specificsite and the number and type of water quality

parameters change significantly during the course ofthe time series, meaningless conclusions may bedrawn.

c) Care should be taken with older data. Many datasets can go back to times when the sensitivity ofanalytical methodology was considerably less thanwith more modern methods. This is of particularconcern in cases where there are older results thatappear to be just above the detection limit. Forexample, metals data generated in the 1970’s mayhave been obtained using colorimetric methods withdetection limits significantly above current waterquality objectives. All analytical methods arecapable of producing ‘false positive’ results andincorporation of these into the index can providemisleading conclusions. For example, if oldercadmium data was derived from a method with adetection limit of 0.01 mg∙L-1 there will probably beresults at (or slightly above) the detection limit.These may or may not be valid. If these data arerun in the index against an objective of 0.0002mg∙L-1 false positives will represent very largeexcursions over the objective and questionableindex values will result.

d) The index should be run on parameter setsrelevant to the water body being tested. Severaljurisdictions, including Ontario and Québec haveolder data sets where large suites of parameterswere tested. The CCME WQI should only include‘relevant’ parameters in the calculation. Because ofthe way the index is calculated, the inclusion ofmany parameters (for example, all pesticides in a‘scan’) may result in unrealistically low indexvalues. For example, gas chromatographic – massspectrometer scans will often provide large amountsof data on many chemicals simultaneously.Including all of these data in index calculations willartificially depress the index value. This will be ofparticular concern in trend-through-time indexevaluations when the number of tested parametersvaries significantly, or in situations wherecomparisons between sites is desired.

e) Minimal data sets should not be used. TheCCME WQI was not designed to replace properevaluation of water quality conditions throughthorough assessment of water quality chemicals ofconcern. The CCME WQI should not be run withless than four parameters and four sampling visitsper year.



13

Despite these restrictions on its use, the CCME WQI hasbeen successfully applied in several Canadianjurisdictions and has produced values that containvaluable information with regard to trends through timeand spatial discrimination of impacted and non-impactedsites. The committee feels that it has application as amanagement and communication tool if appliedappropriately.

References

1 Couillard, D. and Lefebvre Y. 1985. Analysis of water qualityindices. J. Environ. Mgmt. 21: 161-179.

2 Smith, D.G. 1990. A better water quality indexing system for riversand streams. Wat. Res. 24(10): 1237-1244.

3 House, M.A. and Ellis, J.B. 1987. The development of waterquality indices for operational management. Water Sci. Technol.19(9): 145-154.

4 Saeger, J. 1994. Developments in water quality standards andclassification schemes in England and Wales. Water Sci.Technol. 30: 11-19.

5 Zandbergen, P.A. and Hall, K.J. 1998. Analysis of the BritishColumbia Water Quality Index for watershed managers: A casestudy of two small watersheds. Water Qual. Res. J. Canada.33(4): 519-549.

6 Hébert, S. 1996. Développement d’un indice de la qualitébactériologique et physico-chimique de l’eau pour des rivières duQuébec. Report of the Ministière de l’Environnement et de laFaune.

7 Rocchini, R. and L.G. Swain. 1995. The British Columbia WaterQuality Index. Water Quality Branch, Environmental Protection

Department, British Columbia Ministry of Environment, Landand Parks. 13 pp.

8 B.C. Ministry of Environment, Land and Parks. 1996. BritishColumbia Water Quality Status Report. 181 pp.

9 Manitoba Environment. 1997. Moving Towards SustainableEnvironment Reporting. http://www.gov.mb.ca/environ/pages/soe97/index.html.

10 Munger, S. 1996. A Canadian water quality index: A discussionpaper for obtaining relevant national data and the refinement ofmethods. Prepared for Indicators Branch, State of theEnvironment Directorate, Environment Canada. 12 pp + tablesand graphs.

11 Hart, W. 1998. Alternative formulations of factors used in theBritish Columbia Water Quality Index. Report submitted to theTechnical Subcommittee of the CCME Water Quality GuidelinesTask Group. February, 1998.

12 Phippen, B. 1998. Application of the National Water Quality Indexprototype in British Columbia. BWP Consulting, 60 pp. June,1998.

13 Husain, T. 1998. Application of the National Water Quality Indexprototype in Newfoundland. Prepared for State of theEnvironment Task Group, Canadian Council of Ministers of theEnvironment. 57 pp. May, 1998.

14 Wright, C.R., Saffran, K.A., Anderson, A-M., Neilson, D.,MacAlpine, N., and Cooke, S. 1998. A Water Quality Index forAgricultural Streams in Alberta. 17 pp + appendices. November,1998.

15 Khan, H. The CCME Water Quality Index 1.0 - Application to

Three Watersheds in Newfoundland. November 1999

Reference listing:

Canadian Council of Ministers of the Environment. 2001. Canadian water quality guidelines for the protection of aquatic life: CCMEWater Quality Index 1.0, Technical Report. In: Canadian environmental quality guidelines, 1999, Canadian Council of Ministers of theEnvironment, Winnipeg.

For further scientific information, contact:

Environment CanadaGuidelines and Standards Division351 St. Joseph Blvd.Hull, QC K1A 0H3Phone: (819) 953-1550Facsimile: (819) 953-0461E-mail: [email protected]: http://www.ec.gc.ca

© Canadian Council of Ministers of the Environment 2001Excerpt from Publication No. 1299; ISBN 1-896997-34-1

For additional copies, contact:

CCME Documentsc/o Manitoba Statutory Publications200 Vaughan St.Winnipeg, MB R3C 1T5Phone: 1-800-805-3025 (toll-free) or (204) 945-4664Facsimile: (204) 945-7172E-mail: [email protected]

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