Water Testing Project for the North Fork River
Stream flow
(cfs)
Physical Properties
Stream Channel
Pattern
Substrate
pH
Dissolved Oxygen
Water testing
day is
FridayMay 11th
at the North
Arm Trailhead.
Watershed
System
Chemical Properties
Temperature
Nutrients
Turbidity
Riparian Zones
Biological Properties
Macroinvertebrates
Physical Properties of a
Watershed System
Stream Flow
Stream Shape
Stream Flow
The amount of water
that flows past a
specific point in a
stream over a period
of time.
Natural Influences
that affect Stream Flow
•
•
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•
•
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Climate
Season
Watershed
Meandering
Substrate
Groundwater
Vegetation
Human influences affecting stream flow
Dams
Channelization
Land use
Why do we care about Stream
Flow?
• Water quality : affects turbidity (sediment load) and
dissolved oxygen
• Aquatic life : creates different habitats for fish and bugs
•Vegetation: needs overbank flooding for nutrients
•Flooding: controlled for human structures
•Water storage: determines how and when water
should be stored
1. Measure a 10 m section and mark it with rocks.
2. Throw a stick in above this section and use a stop watch to
measure the time it takes the stick to travel the 10 m
section 3 separate times. Average the times.
3. Divide the average time (sec) by the distance (10m) to get
the velocity (m/s).
4. Measure the depth (m) & width(m) to find an area (m2).
5. Stream flow = velocity (m/sec) x area (m2)
What influences
stream shape?
Substrate Type
Stream Channel Pattern
Riffle/ Run /Pool Ratio
Substrate Types
Silt
Gravel
Sand
Boulders
Cobble
Bedrock
Method for Recording observations of substrate
1. Step into the stream, without looking bend
down and pick up some sediment.
2. Tell your partner the type of substrate you are
holding, have them record the type with a tally
mark.
3. Take 50 samples in and along the river section.
4. Tally your total number of observations for each
type of substrate.
5. Multiply the number of observations of each
type by 2. This will equal the % out of 100 for
each substrate.
Stream Channel Patterns
Top View of Stream
meandering
straight
braided
Cross-section view
Meandering Stream
Found in
valley bottoms
without much
slope. Slower
Velocity.
Big pools,
some riffles
and runs
Mixture of
sand bars
& suspended
silt particles.
Straight Stream
Steep gradient, fast flowing
Substrate is predominantly cobble and gravel
Mostly runs some riffles
Braided Stream
River continually splits
and rejoins. River moves
across broad flat
plains. Slow and
fast velocities.
Mostly runs and
riffles.
Mixture of silt,
Sand, and gravel.
Habitat areas of a
Stream Channel
Run
Run
run
Riffles have high oxygen amounts essential for
macroinvertabrates (bugs) and spawning fish.
Runs where fish feed and travel
Pools where fish hide
and rest from the current
Method for Recording Riffle Run Pool Ratios
1. Take one step next to your river section, look
across the river.
2. Record a tally mark on your sheet that shows
if you see a riffle, run, or pool
3. Make 50 observations.
4. Total the tally for each characteristic.
5. Multiply the totals by 2 to find the % riffle,
run or pool that your river section contains.
• Friction created by substrate
• Velocity
• Vegetation
Development, logging, mining, grazing can destroy vegetation which
causes more water and sediment to drain directly into a stream rather
than being filter through groundwater.
Channel alterations, ie. straightening of a stream along a highway or
through a city center
Dams prevent downstream flooding but then stream nutrients are not
distributed throughout the floodplain to plants.
Why do we care about stream
shape?
 Stream shape affects water quality
Straightening of a stream increases velocity, which
results in higher erosion rates and more turbidity
Darker streams impact temperature and amount of
sunlight that reaches plant life.
 Stream shape affects habitat.
A straight stream does not have the variety of habitats
found in a meandering stream
 Stream shape impacts flooding
How will you interpret your
results?
Physical Characteristics of the river will be correlated to the
chemical and biological parameters.
Some Examples:
Channel pattern and shape will effect velocity and erosion which
will in turn effect temperature and oxygen and/or nutrients.
Substrate will be related to velocity and oxygen which will
determine how many bugs are in the river.
Riffle/Run/Pool ratio will indicate the diversity of the aquatic
habitats and in relation to this the diversity of life in the stream.
High diversity correlates to high water quality.