WATER ASSESSMENT AND TESTING

Introduction to Watershed ScienceIntroduction to Watershed Science

Merritt CollegeMerritt College

Marc Epstein, InstructorMarc Epstein, Instructor

WATER MONITORING BASICS

Collection of Data Episodic (such as a spill) Synoptic (like snapshot day) Periodic and on a regular basis Continuous over long period of time

Consistent collection methods

ANALYSIS DEFINED

An investigation into whether a waterbody can support the beneficial uses assigned to it.

Water quality monitoring is commonly defined as the

sampling and analysis of water (lake, stream, river, estuary, or ocean) and conditions of the

waterbody.

TYPES OF MONITOING

Biological

Chemical

Physical

BIOLOGICAL Include measures related

to the plant and animal life of the water body, such as:

Fish species diversity and abundance;

Presence or absence of indicator fishes, aquatic invertebrates, or aquatic plants.

CHEMICAL

Include contaminants such as: Metals Dissolved nutrients Oils Pesticides

Chemical properties of the aquatic system such as: Dissolved oxygen Chemical oxygen demand Acid neutralizing capacity

PHYSICAL

Include general conditions such as: Temperature Flow Sediment characteristics Water color Within-channel habitat structure

WHAT IS KWEST MONITORING Total Maximum Daily Load (TMDL) A calculation of the maximum amount of a pollutant that a

waterbody can receive and still meet water quality standards, and an allocation of that amount to the pollutant's sources.

Water quality standards are set by States, Territories, and Tribes. They identify the uses for each waterbody, for example, drinking water supply, contact recreation (swimming), and aquatic life support (fishing), and the scientific criteria to support that use.

A TMDL is the sum of the allowable loads of a single pollutant from all contributing point and nonpoint sources.

The calculation must include a margin of safety to ensure that the waterbody can be used for the purposes the State has designated.

The calculation must also account for seasonal variation in water quality. (From federal Clean Water Act)

THE BASIC FIVE WATER QUALITY VITAL SIGNS

Temperature Dissolved Oxygen pH Conductivity and

Salinity Turbidity

TEMPERATURE Measure of average kinetic energy of water

molecules Affects water chemistry and aquatic organisms Influences: Amount of oxygen that can be dissolved Rate of photosynthesis Metabolic rate of organisms Sensitivity of organisms to toxic waste,

parasites, and diseases Timing of reproduction and migration of

organisms

Code(Note a)

Device Cost Labor Application Limitations Major sources of error

TR Bulb thermometers

$5-20 1 minute Air, Surface water, or sample in jar

Low resolution (0.5 C to 1 C)

Inaccurate setting by manufacturer, disconnection of capillary tube from scale, air bubbles in tube

TRM U-shaped Min-Max thermometer

$25 1 minute Air, incubation chambers

Low resolution (1 C). Not recommended for field use (mercury)

Inaccurate setting by manufacturer, disconnection of capillary tube from scale, air bubbles in tube, incomplete resetting

TT Digital Thermometer

$25 2 min Air, Surface water, inside soil or sediment

Needs batteries

Inaccurate setting by manufacturer, drift from original setting

TT Thermistor probes var Vertical gradients Response depends on length of cable

Inaccurate setting by manufacturer, drift from original setting

TH Hobo-Temperature Data loggers

$60-100

10 min (program) 10 min download, plus deployment labor

Continuous measurements of temperature in the environment

Requires use of computer, need to buy software

Inaccurate setting by manufacturer, drift from original setting

TTP Sonde/datalogger probe

~$4,000 for entire Sonde

1 min Discrete or continuous measurements

Requires use of computer, need to buy software

Inaccurate setting by manufacturer, drift from original setting

DISSOLVED OXYGEN

The amount of oxygen dissolved in water Aquatic organisms need oxygen to survive and grow

Consequences of insufficient dissolved oxygen: Death of adults and juveniles Reduction of growth Failure of eggs/larvae to survive Change of species in given water body

Code (Note a)

Principle

Device Resolution

(@range)

Cost(Note b)

Labor Limitations Extent of Error(Note c)

DOC Colorimetric

Reagent ampoules (Note c) and comparator (e.g., “CHEMets” by Chemetrics)

1 mg/l (1-6)2 mg/l (6-12)

$36/20 tests measure 3 min.

1 mg/l (1-4)2 mg/l (4-8)4 mg/l (8-12)

DOC Colorimetric

Reagent ampoules (Note d) and comparator (e.g., “AccuVac” by Hach)

0.2 mg/l (0-15)

$78/25 tests measure 3 min.

Leaky seal leads to continuous color development

1 mg/l

DOW Titrimetric Modified Winkler Method kit: DO bottle, reagents, vial and syringe for titration

0.2 mg/l (0-15)

$50 /100 tests measure 8 min.

“Sliding” endpoint.

0.5 mg/l

DOE Polarographic

D.O. meter+electrode 0.05-0.2 mg/l (0-20)

$800 prep/calib. 1 hmeasure 0.5-3 min.

Requires expertise and experience

5%

DOP Polarographic

Rapid-Pulse probe, for Sonde (e.g., YSI or Hydrolab)

0.1 mg/l (0-20)

~$4,000 for entire Sonde

prep/calib. 2 hDownload 1 hr

Requires expertise and experience

5%

pH Measure of acidic vs. basic – strength of

Hydrogen ion Lower value more acidic – Higher value

more alkaline Aquatic organisms require narrow pH Extreme pH damages fish gills,

exoskeleton, and fins Changes in pH may cause or change

chemical reactions

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Code (Note a)

Device Range Resolution (pH units)

Cost Labor Limitations Extent & Sources of Error (pH units)

PHLQ Liquid pH kit 2-10 2 $4 /50 tests

2 min Daylight only

2; Aging of indicator

PHLQ Liquid pH kit 5-10 0.5 $8 /50 tests

2 min Daylight only

1 Aging of indicator

PHST Universal pH strip (Note b)

1-14 1 $12 /100 tests

3 min Daylight only

1 Aging of indicator, slow response

PHST “Environmental” pH strip (Note b)

5-10 0.5 $12 /100 tests

3 min Daylight only

0.5 Aging of indicator, slow response

PHST “Physiological” pH strip (Note b)

6.5-10 0.3 $12 /100 tests

3 min Daylight only

0.3 Aging of indicator slow response r

PHEL Pocket meter with dry electrode

1-14 0.1 $60 10 min cal, 3 min measure

Need to rehydrate

0.3 Standard buffer drift, slow response

PHEL Multi-meter pH probe

1-14 0.1 variable 10 min cal, 3 min measure

0.3

PHP Sonde/datalogger probe

1-14 0.01 ~$4,000 for entire Sonde

10 min cal, 3 min measure

0.1

CONDUCTIVITY / SALINITY Conductivity is the ability of the water to conduct

electrical current Salinity is a measure of the amount of salts in

the water Salts (solids in dissolved form) break into

positively and negatively charged ions Conductivity and salinity increase with the

amount of salts in the water Salts affect the quality of water for drinking and

irrigation Various species have specific salinity tolerances

Code (Note a)

Principle Device Range Resolution Cost Labor Applications Extent & Sources of Error (percent of measured value)

EC Electrical conductance

Conductivity meter

0 to 200 microS

1 microS $60 2 min Snowmelt, rainwater

5% uncompensated temperature effectDrift, source of Standard

EC Electrical conductance

Conductivity meter

0 to1990 microS

10 microS $60 2 min Freshwater “

EC Electrical conductance

Conductivity meter

0 to19.90 miliS

100 microS (0.1 mS)

$60 2 min Freshwater, Brackish water

“

ECP Electrical conductance

Sonde/data logger probe

var var ~$4,000 for entire Sonde

2 min all 5% Drift, source of Standard

SAL Electrical conductance

Salinity probe

2 to 40 ppt(Note b)

varies Part of a package $800 or more

Brackish and Seawater

5%Drift, source of Standard

REF Refractive index

Refractometer

2-100 ppt(Note c)

1 or 2 ppt $150 1 min Brackish, Seawater,hypersaline ponds

10%

HYD Specific gravity

Hydrometer 16-40 ppt(Note d)

1 ppt $10 1 min Brackish and Seawater

10%

HYD Specific gravity

Hydrometer 2-100 ppt 1 ppt $30 (inc jar) 3 min Brackish, Seawater,hypersaline ponds

5

Gravimetric Total dissolved solids (TDS)

all 0.1 mg/l Lab method 5

TURBIDITY

Amount of suspended particles including Algae, suspended sediment, and organic matter

Suspended particles: Diffuse sunlight – reducing light Absorb heat – Increase temperature Clog fish gills Foul gravel beds Smother fish eggs and benthic insects

Code (Note a)

Principle Method name (Parameter, unit)

Cost Labor Application Limitation Extent & Sources of Error

Transparency Murkiness (Note b)

None 30 sec Turbidity watch, source ID

Not Applicable

SEC Transparency Secchi disk (Secchi depth, cm)

~$30 2 min Status of Lakes and pools

Need to deploy from above Daylight only

30%; Individual operator’s vision, Lighting, surface reflection, depth measurements

TRT Transparency Transparency tube (Transparency, cm)

$40 5 min Turbidity in streams Source ID

Daylight only 30%; Individual operator’s vision Length measurement, deposition

TUJ Transparency match

Dual cylinder (Jackson turbidity, JTU)

$40 5 min Turbidity in streams Source ID

Daylight only 40%; Individual operator’s vision, quality of standard, volume measurements

TUN Light-scattering Nephelometer (Turbidity, NTU)

$300 and up

10 min cal 1 min measure

Turbidity in streams and lakes, Source ID

Error variable, depending on instrument

TUN Light-scattering Automated Nephelometer (Turbidity, NTU)

$1000 and up

Installation, calibration, download.

Use with data logger and/or trigger, storm events

Fouling of light absorbing surfaces, drift from the calibrated state

TSS Gravimetric: Dry Weight per volume of sample aliquot (Note c)

Filtration for Total Suspended Solids (TSS, mg/l)

$2000 and up

20 min Sediment loads assessments

Requires laboratory facility

Error variable, depending on operating procedures

SSC Gravimetric: Dry Weight per volume (by water weight) of whole sample

Filtration for Suspended Sediment Concentration (SSC, mg/l)

$2000 and up

20-60 min Sediment loads assessments

Requires laboratory facility

Error variable, depending on operating procedures

IC Sinking Imhoff Cone Method

~$30 5 min (setup and read)

Finer Separation by density

Requires cones 30%; Lighting, surface identification, volume measurements

BEYOND THE FIVE BASIC VITAL SIGNS

Nitrogen Large amount introduced creates

excessive algal growth resulting in depleted dissolved oxygen

Phosphate When amounts become elevated algal

blooms can occur depleting dissolved oxygen

Bio-Assessment

Survey of benthic aquatic macro invertebrates

Survey of physical habitat