Measuring Water Pollution

1. Measuring Water Pollution A Quick Overview

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

3. TECHNOLOGY-BASED LIMITS: Use a certain treatment technology (BPT, BAT, MACT, BPJ) to achieve a given quality of effluent WATER QUALITY-BASED LIMITS: Quantitative relationship between inputs and quality (LD50, NOEL)--dose/response risk assessment, hydrology, mass balance Two Basic Approaches:

4. The “Conventional” Pollutant Measures: • Oxygen (BOD, COD, DO) • Solids content (TSS, Conductivity, Secchi disk, settleable solids) • Nutrients (phosphorus, nitrogen) /Algae/Eutrophication • Acidity (pH) • Bacteria (e.g., fecal coliform) • Temperature

5. Fire Metabolism of humans and animals Fate of pollutants in water C in fuel combines with atmospheric O2 carbon-bearing organic compounds oxidized to CO2,water, energy pollutants are oxidized, depleting O2 in water Oxidizing (Oxygen-Using)Reactions

6. Measures of oxygen in water: • Dissolved oxygen (DO)--time and space variables, dilution • Biological oxygen demand, five days (BOD5) • Chemical oxygen demand (COD) • Sediment oxygen demand (SOD)

7. Oxygen and other pollutants may vary according to: • Fluctuations in inputs (lagged) • Time of day (day-night) • Time of year (summer-winter) • Water temperature (thermal stratification) • Stream flow • Which in turn varies with land clearance/impervious cover, storm events, seasonal variations, channel structure, etc.

8. Effects of sediment loading • Destruction of spawning beds • Adsorption and transport of other pollutants • Reduced light penetration, aquatic vegetation • Greater nutrients loadings, oxygen demand • Interference with navigation, flood control, recreation, industry

9. Effects of nutrient loadings (N, P measured by Chlorophyll a, Secchi, algal species) • Algae blooms • DO changes, fish kills • Shift of trophic status toward eutrophic • Drinking water impairment (direct and indirect) • Aesthetics (color, clarity, smell) • Uptake and release of toxics

10. Effects of acidification(measured in pH--log scale) • Direct kill of living things • Shift toward acid-tolerant species • Mobilization (dilution, desorption) of metals and other toxics

11. What about toxics?

12. Impacts of toxics • Acute mortality (instant death) • Chronic illnesses (e.g., cancer) • Reproductive and developmental toxicity (“hormone mimics”) • Persistence over space (toxaphene) and time (PCBs); or transformation (DDT to DDE, PCB dechlorination, methyl mercury) • Storage in reservoirs (sediment sinks)

13. Some approaches to toxics parameters • Chemical levels (water, sediment) • Ability to support designated uses • Ability to support beneficial uses • Fish advisories • Historical baselines • Background levels • “Narrative criteria” (no toxics in toxic amounts)

14. Indices Bring diverse measurements together into a single-number value

15. Ecosystem approaches • Look at interactions of living and nonliving parts of the ecosystem (what’s an ecosystem?) • Try to identify stresses and responses • Holistically integrate physical, biological, and social aspects of the area in question

16. “Social Indicators” • Stewardship • Sustainability • Stakeholder Involvement • Etc., etc. (what is the good society?)