Kuskokwim Watershed Council

Key Parameters for Baseline Water Quality

Assessment

© David Griso

Baseline Water Quality Data

• Consistent sampling over time (~3 years)– Recommend sampling 1-2 times/month in

summer and once in winter

• Documents current water quality conditions• Compare with EPA and ADEC water quality

standards to determine exceedances• Used to identify problems and for future

comparisons

Baseline Site Selection• Representative sites

• Accessible year round• Generally pristine, untouched areas

Water Sample Collection• Ideally, collect sample at

– middle of stream (highest flow) – on straight away – at mid-depth

Water Quality Water Quality ParametersParameters

The “Vital Signs”• Temperature• pH• Specific Conductance• Dissolved Oxygen

YSI 556 Multi-probe

Water TemperatureWater Temperature

• Aquatic organisms are temperature- sensitive

• Temperature affects dissolved oxygen

• Affected by season, erosion, reduced streamflow, etc.

• Indicator of Climate change

© Renee Fredericks

pH• Measures how acidic/basic the water is• Naturally determined by geology

– Areas with Limestone bedrock have higher pH

• pH of streams/lakes change naturally throughout day—photosynthesis

• Can be affected by acid mine drainage, pollution (lead acid batteries)

Source: http://staff.jccc.net/pdecell/chemistry/phscale.html

pH Scale

Specific Conductance

• Measures the ability of water to pass an electrical current

• Indicator of the amount of dissolved minerals in the water (salts, metals, ions)– A good “screening” test for heavy

metals• Petroleum products do not affect

conductivity readings

Dissolved Oxygen

• DO is the oxygen dissolved in water• DO is important for organisms to

grow, develop, and survive• DO comes from aeration (rapids),

photosynthesis, other chemical reactions

• Primary indicator of a stream’s ability to support fish

Sampling for Pike in the mouth of the Johnson river © David Griso

ADEC Water Quality Standards

• Temperature– Drinking H20 < 15 ºC, spawning areas/egg &

fry incubation < 13 ºC

• pH– Drinking H20 = 6.0 to 8.5

• Specific Conductance– No standard

• Dissolved Oxygen– Drinking H20 >4 mg/L, >7 mg/L for waters

with resident or anadromous fish

Turbidity

• Cloudiness of the water• Natural causes: suspended sediment,

micro-organisms, glacial silt• Human causes: roads, logging,

construction

http://or.water.usgs.gov/proj/or00311/index.html

Turbidity

Nephelometric Turbidity Units

• ADEC standard: not more than 5 NTU above baseline conditions when < 50 NTU- We need to know what baseline is!

• High turbidity can clog fish gills, cover plants, increase water temperature

www.hach.com

www.lamotte.com

Any Questions?

© David Griso