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ENVIRONMENTAL WATER QUALITY IN WATER RESOURCES MANAGEMENT Tally Palmer, Robert Berold and Nikite Muller Unilever Centre for Environmental Water Quality Institute for Water Research Rhodes University. THANK YOU FOR BEING HERE - BUT WHY DO YOU NEED TO BE HERE ?. there is a new water law
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ENVIRONMENTAL WATER QUALITY IN WATER RESOURCES MANAGEMENT Tally Palmer, Robert Berold and Nikite Muller Unilever Centre for Environmental Water Quality Institute for Water Research Rhodes University
THANK YOU FOR BEING HERE - BUT WHY DO YOU NEED TO BE HERE ? • there is a new water law • it requires resource protection + optimal resource use • for the law to work YOU need to buy in and comply • To buy in you need to know: - the new thinking and requirements - the inadequacy of present monitoring
PRESENTATION STRUCTURE Introduction • EWQ, water law and resource protection • EWQ – an integrated approach • EWQ application within the NWRS • Case Study
EWQ water law and resource protection
MAIN PRINCIPLES OF THE NWA equity fairness to people now sustainability fairness to people in the future and to the environment
Rivers Lakes and dams Wetlands Estuaries Sea (not governed by NWA) WATER RESOURCE whole hydrological cycle – with most residence time in aquatic ecosystems
BIOPHYSICAL ENVIRONMENT: BIOTIC + ABIOTIC flow water quality physical structure NB! functions and interactions microbial systems instream vegetation - fish water invertebrates • substrate riparian vegetation people
water supply waste transport, processing & dilution natural products biodiversity flood control recreation aesthetic/spiritual needs social and economic benefits triple bottom line ecosystem services RDM SDC resource protection
WATER RESOURCE USE AND PROTECTION • water resource protection assures long term resource use • generally resource use reduces ecosystem health • therefore resource use needs to be balanced with resource protection
means look after and use wisely it does not mean keep separate and do not use all or nothing use for economic and social development is essential use for poverty alleviation is essential PROTECTION and USE THEREFORE we must decide which areas and ecosystems are used more intensively, and which need more protection
water supply waste transport, processing & dilution natural products biodiversity flood control recreation aesthetic/spiritual needs WHAT AQUATIC ECOSYSTEMS DO FOR PEOPLE BUT Ecosystems cannot provide ALL these goods and services AT THE SAME TIME IN THE SAME PLACE people have to CHOOSE
RESOURCE CLASSIFICATION objective, organised basis for choice Ecological Reserve methods SPATSIM: WEBSITE page 73
Moderately modified Critically modified Largely modified Largely natural Natural Ecological Reserve Categories A B C D E&F Reference condition Natural Good Fair Poor Water Resource Classification Protected Unacceptable
EWQ an integrated approach
EWQ WATER CHEMISTRY, LIVING ORGANISMS & THEIR INTERACTIONS • Three data sources and approaches: • water chemistry • biomonitoring • ecotoxicology
WATER CHEMISTRY • water + dissolved and suspended particles - toxic constituents e.g. metal ions, pesticides,endocrine disruptors - system variables e.g.T°C, pH, DO, TDS,TSS - nutrients e.g. nitrite,nitrate, phosphate • Selected variables collected as WQ data at DWAF monitoring sites
CHEMICAL DATA • Low frequency (monthly sampling) • Low range of variables analysed • Sampling convenience, not necessarily best location • Site-specific data necessary – natural water chemistry differences • DWAF database • Provides information on variability + trends: essential first step
A comparison of monthly TDS concentrations at a reference site (box plots) and a present state site (whisker plots) in the Olifants River upstream of the confluence with the Steenkoolspruit
BIOMONITORING - habitat (IHAS, HAM) - invertebrates (SASS or BioTrack) - fish - geomorphology - data collected as part of the National River Health Programme
BIOMONITORING DATA • provides a biologically integrated picture of water quality • e.g. invertebrate monitoring – SASS/Biotrack presence, absence abundance of taxa • useful “red flags” of deteriorating conditions, but no link between cause and effect Thermometer…..
ECOTOXICOLOGY - cause and effect links - concentration response relationship - freshwater toxicity tests - acute and chronic tests - data in international and national data-bases
TOXICITY DATA • relate biological response (tolerances) to concentrations of chemicals at which organisms are affected: concentration-response data • provides a link between water chemistry and biological monitoring data
ADVANTAGES OF THE INTEGRATED APPROACH • There are limitations to chemical, toxicological and biomonitoring data • Water chemistry provides only limited information about river health but is widely recorded • Biomonitoring adds an integrating and biotic-response dimension • Toxicity data quantitatively link the chemistry and the biotic response • Use of a combination of all 3 approaches maximises the value of each data-set
OTHER ABIOTIC DRIVERS: FLOW AND STRUCTURAL HABITAT sandy bottom cobbles, gravel, boulders bedrock Olifants River
EWQ - APPLICATION WITHIN THE NATIONAL WATER RESOURCES STRATEGY
CATCHMENTS : UNITS OF WATER RESOURCE MANAGEMENT
PLAN Analyse the Reseve – ecospecs Analyse user needs – userspecs Describe catchment characteristic Stakeholder participation
Catchment vision: Decide on Class Set RQOs STRATEGY DO RDM & SDC MONITOR
OLIFANTS RIVER(Gauteng / Mpumalanga) • Land-use is agricultural, industrial and mining • Sulphate salinisation significant • Localised nutrient enrichment
EWQ – DEVELOPMENT OF WATER QUALITY METHOD IN ECOLOGICAL RESERVE Water Chemistry - salinity first guess at class boundaries: each class was defined by a % deviation from natural Good = 20% Fair = 30% Poor = 40%
Salinity analysed – • most reaches >40% deviation from natural • = Poor • BUT: • Biomonitoring…..
BIOMONITORING Total SASS score & average score per taxon (ASPT) related to classes Class SASS Score ASPT Natural >175 >7 Good 120 –175 6-7 Fair 60 – 120 4.8-5.9 Poor <60 <4.8
Biomonitoring data analysed reaches in a variety of conditions: Natural, Good, Fair and Poor so – bugs and fish were happy with >40% increase in salt reducing salinity expensive and difficult don’t do more than is needed Ecotoxicology…….
RELATE TOXICITY ENDPOINT TO CLASSES Class Toxicity endpoint: protect 95% species Natural No chronic toxicity Good Fair No acute toxicity Poor
Biomonitoring and water chemistry classification much better aligned Class boundaries indicated by tolerances (ecotox) mainly match with those indicated by organisms present (biomonitoring) Some reaches “Poor” biomonitoring Fair/Good salinity Check for instream toxicity 2 of 5 sites - instream toxicity
OVER PROTECTION AND UNDER PROTECTION ARE BOTH EXPENSIVE • EWQ cost effective for - setting objectives - monitoring to meet objectives - instream - end-of-pipe • EWQ is now the basis for water quality aspects of ecological Reserve determinations
OLIFANTS RIVER PRESENT ECOLOGICAL STATE The challenge of integration and real decisions….