Measuring Water PollutionMeasuring Water Pollution

A Quick OverviewA Quick Overview

How do you measure the How do you measure the quality of a moving, ever quality of a moving, ever changing fluid medium?changing fluid medium?

Two Basic Approaches:Two Basic Approaches: TECHNOLOGY-TECHNOLOGY-

BASED LIMITS: BASED LIMITS: Use a certain Use a certain treatment treatment technology (BPT, technology (BPT, BAT, MACT, BPJ) BAT, MACT, BPJ) to achieve a given to achieve a given quality of effluentquality of effluent

WATER QUALITY-WATER QUALITY-BASED LIMITS: BASED LIMITS: Quantitative Quantitative relationship relationship between inputs and between inputs and quality (LDquality (LD5050, , NOEL)--dose/responNOEL)--dose/response risk assessment, se risk assessment, hydrology, mass hydrology, mass balancebalance

The “Conventional” The “Conventional” Pollutant Measures:Pollutant Measures:

Oxygen (BOD, COD, DO)Oxygen (BOD, COD, DO) Solids content (TSS, Conductivity, Solids content (TSS, Conductivity,

Secchi disk, settleable solids)Secchi disk, settleable solids) Nutrients (phosphorus, nitrogen) Nutrients (phosphorus, nitrogen)

/Algae/Eutrophication/Algae/Eutrophication Acidity (pH)Acidity (pH) Bacteria (e.g., fecal coliform)Bacteria (e.g., fecal coliform) TemperatureTemperature

Oxidizing (Oxygen-Using)Oxidizing (Oxygen-Using)ReactionsReactions

FireFire

Metabolism of Metabolism of humans and humans and animalsanimals

Fate of pollutants Fate of pollutants in waterin water

C in fuel combines C in fuel combines with atmospheric Owith atmospheric O22

carbon-bearing carbon-bearing organic compounds organic compounds oxidized to oxidized to COCO22,water, energy,water, energy

pollutants are pollutants are oxidized, depleting oxidized, depleting OO2 2 in waterin water

Measures of oxygen in Measures of oxygen in water:water:

Dissolved oxygen (DO)--time and Dissolved oxygen (DO)--time and space variables, dilutionspace variables, dilution

Biological oxygen demand, five Biological oxygen demand, five days (BODdays (BOD55))

Chemical oxygen demand (COD)Chemical oxygen demand (COD) Sediment oxygen demand (SOD)Sediment oxygen demand (SOD)

Oxygen and other Oxygen and other pollutants may vary pollutants may vary

according to:according to: Fluctuations in inputs (lagged)Fluctuations in inputs (lagged) Time of day (day-night)Time of day (day-night) Time of year (summer-winter)Time of year (summer-winter) Water temperature (thermal Water temperature (thermal

stratification)stratification) Stream flowStream flow

– Which in turn varies with land Which in turn varies with land clearance/impervious cover, storm events, clearance/impervious cover, storm events, seasonal variations, channel structure, etc.seasonal variations, channel structure, etc.

Effects of sediment Effects of sediment loadingloading

Destruction of spawning bedsDestruction of spawning beds Adsorption and transport of other Adsorption and transport of other

pollutantspollutants Reduced light penetration, aquatic Reduced light penetration, aquatic

vegetationvegetation Greater nutrients loadings, oxygen Greater nutrients loadings, oxygen

demanddemand Interference with navigation, flood control, Interference with navigation, flood control,

recreation, industryrecreation, industry

Effects of nutrient loadingsEffects of nutrient loadings (N, P measured by (N, P measured by

Chlorophyll a, Secchi, algal Chlorophyll a, Secchi, algal species)species)

Algae bloomsAlgae blooms DO changes, fish killsDO changes, fish kills Shift of trophic status toward Shift of trophic status toward

eutrophiceutrophic Drinking water impairment (direct and Drinking water impairment (direct and

indirect)indirect) Aesthetics (color, clarity, smell)Aesthetics (color, clarity, smell) Uptake and release of toxicsUptake and release of toxics

Effects of acidificationEffects of acidification(measured in pH--log (measured in pH--log

scale)scale) Direct kill of living thingsDirect kill of living things Shift toward acid-tolerant speciesShift toward acid-tolerant species Mobilization (dilution, desorption) Mobilization (dilution, desorption)

of metals and other toxicsof metals and other toxics

What about toxics?What about toxics?

Impacts of toxicsImpacts of toxics Acute mortality (instant death)Acute mortality (instant death) Chronic illnesses (e.g., cancer)Chronic illnesses (e.g., cancer) Reproductive and developmental toxicity Reproductive and developmental toxicity

(“hormone mimics”)(“hormone mimics”) Persistence over space (toxaphene) and Persistence over space (toxaphene) and

time (PCBs); or transformation (DDT to time (PCBs); or transformation (DDT to DDE, PCB dechlorination, methyl mercury)DDE, PCB dechlorination, methyl mercury)

Storage in reservoirs (sediment sinks)Storage in reservoirs (sediment sinks)

Some approaches to Some approaches to toxics parameterstoxics parameters

Chemical levels (water, sediment)Chemical levels (water, sediment) Ability to support designated usesAbility to support designated uses Ability to support beneficial usesAbility to support beneficial uses Fish advisoriesFish advisories Historical baselinesHistorical baselines Background levelsBackground levels ““Narrative criteria” (no toxics in toxic Narrative criteria” (no toxics in toxic

amounts)amounts)

IndicesIndices

Bring diverse measurements Bring diverse measurements together into a single-number together into a single-number

valuevalue

Ecosystem approachesEcosystem approaches Look at interactions of living and Look at interactions of living and

nonliving parts of the ecosystem nonliving parts of the ecosystem (what’s an ecosystem?)(what’s an ecosystem?)

Try to identify stresses and Try to identify stresses and responsesresponses

Holistically integrate physical, Holistically integrate physical, biological, and social aspects of the biological, and social aspects of the area in questionarea in question

““Social Indicators”Social Indicators” StewardshipStewardship SustainabilitySustainability Stakeholder InvolvementStakeholder Involvement Etc., etc. (what is the good Etc., etc. (what is the good

society?)society?)