andrew lipsky state biologist usda natural resources conservation service [email protected]...
TRANSCRIPT
Andrew Lipsky
State Biologist
USDA Natural Resources Conservation Service
Rhode island Watershed Stewardship Class: Introduction to Stream Visual Assessment
Providence, RISeptember 26, 2006
Stream Visual
Assessment Protocol (SVAP)
Stream Visual Assessment Protocal-SVAP
One among Many
• All protocols, indices, and assessment tools used to characterize stream condition.
• Vary significantly in required scale, expertise, and data intensity.
VT Agency of Natural Resources
Healthy Stream Ecosystems
Habitat Thresholds Species MX. Weekly
Avg. Temp for
Juveniles
Max Temp. for Survival of
Short Exposure Juveniles
Max Weekly Avg. Temp. for
Spawning
Bluegill 90◦F 95◦F 77◦F
Channel Catfish
90◦ 95◦ 81◦
Largemouth 90◦ 93◦ 70◦
Smallmouth 84◦ 63◦
Brook Trout 66◦ 75◦ 48◦
SVAP
• Qualitative and meant to be conducted with the input and assistance of the landowner
• Allows relatively fast assessment of meaningful stream and riparian characteristics
• Provides the basics for planning stream and riparian conservation practices
Benchmarks
• So, how do you figure out how a stream should “look”???Reference sites – Benchmarks that serve
as examples of relatively unimpacted systems that exhibit a complete set of structural and functional elements
You may have to contact/collaborate with other agencies who have reference site data in the basin of interest
Using SVAP
• Two part approach – Reach identification and assessmentSelect a representative reachIf channel changes dramatically, add
additional reachesDetermine active channel (bankfull) widthAssessment reach = 12 X bankfull width
Example: Bankfull Width = 32 feet
Assess at least 384 feet
Scoring
• Maximum 15 stream elements to score
• Range of scores: 10 (best conditions) to 0 (worst conditions)
• Macroinvertebrates 15 to -3
• Score only elements that are relevant to the reach you are assessing
• Intermediate scoring is allowed
SVAP Assessment
• Two page worksheet with 15 assessment elementsNot all elements are applicable everywhere
in the USOverall score = summation of all scored
values divided by the number scoredEXAMPLE – 12 elements scored
Sum = 82
SVAP Score = 82/12 = 6.8 (Fair)6.8 (Fair)
Bankfull Channel Width
• Determines the length of the assessment reach
• Numerous field indicators to determine bankfull channel width; some stronger according to physiographic region
• ALWAYS try to measure bankfull channel width just upstream of a hydraulic control– Riffles, bedrock outcrops, waterfalls, etc.
Bankfull Channel Width
K. Gullett photo
Embryonic active floodplain developing in incised channel. Stage IV of channel evolution.
a. Abandoned floodplain b. Active floodplain indicating bankfull stage
Adapted from Vermont Stream Geomorphic Assessment
VT Agency of Natural Resources
SVAP Scoring Elements
Channel Condition
Channel Condition
Hydrologic Alteration
Hydrologic Alteration
Riparian Zone
Right Bank No BufferEmergent Vegetation boundary
Left Bank Narrow Riparian Buffer
Sept.18, 2004 Flood level in Town hay field
Bank Stability
K. Gullett photo U. of Wash. photo
Bank Stability
Water Appearance
Water Appearance
K. Gullett photo
Nutrient Enrichment
Nutrient Enrichment
M. Zuroske photo
D. Orth photo
Barriers to Fish Movement
Barriers to Fish Passage-A regional and local perspective
Dams of the Eastern United
States
Barriers to Fish Passage in RI
Impacts of River and Stream Dams/Crossings
– Habitat loss and degradation
– Alteration of Ecological Processes
– Population fragmentation & isolation
– Reduced access to vital habitats
– Disruption of processes that maintain regional populations
K. Gullett photo K. Gullett photo
USFS photo
Passage Barriers
The RI River & Stream Continuity Project
Watershed ApproachThe RI River & Stream Continuity ProjectRoad Crossings as Potential Barriers to
Wildlife and Fish Movement
American Shad Declines on the Pawcatuck River
0
1000
2000
3000
4000
5000
1979
1981
1983
1985
1987
1989
1991
1993
1995
1997
1999
2001
2003
2005
Alosids: Declining Populations
Current Commercial Shad Harvest 5% of Historic Catch
Data provided by RIDEM Fish & Wildlife
River Herring Decline at Two Rhode Island Rivers
0
50,000
100,000
150,000
200,000
250,000
300,000
350,000
1999 2000 2001 2002 2003 2004 2005
Ab
un
dan
ce
Gilbert Stuart Nonquit
Instream Fish Cover
Aquatic Habitats – formed by the free movement of water and materials, during high flows
Habitat Structure
Bass/sunfish
Brook troutMinnows/sucker
Fish and Invertebrate
Habitat
Instream Fish Cover
U. of Wash. photo
Pools
A stream with many pool types will support a wide variety of aquatic species. Rivers with low sinuosity (few bends) and monotonous pool characteristics do not have sufficient quantities and variety of habitat to support a diverse aquatic community. An even mix of all pool types is most desirable. In the absence of some pool types, it is better to have deep pools over shallow pools. All small-shallow pools or lack of pools entirely are the least desirable conditions.
Pools
• Refuge for fish during low flow, drought periods
• Resting and feeding area
• Refuge from predators
Stream Bed Terminology• Riffles: the sections of the bed with the steepest slopes and shallowest
depths at flows below bankfull. Riffles typically occur at the cross over locations and have a poorly defined thalweg.
• • Runs: differ from riffles in that depth of flow is typically greater and slope of the bed is less than that of riffles. Runs will often have a well defined thalweg.
• • Pools: are the deepest locations of the reach. Water surface slope of pools at below bankfull flows is near zero. Pools are often located at the outside of meander bends.
Stream BedTerminology• • Glides: are located immediately downstream of pools. The slope
of the channel bed through a glide is negative while the slope of the water surface is positive. The head of the glide can be difficult to identify. Use the following characteristics to help you locate the head of the glide:
– the location of increased flow velocity coming out of the pool, – the location at which the steeply sloped bed rising out of the pool
decreases to a lesser gradient, – the location at which the thalweg coming out of the pool
becomes less well defined and essentially fades completely. – the location which is approximately same elevation as the tail of
the run
Invertebrate Habitat
Invertebrate Habitat
Canopy Cover
Canopy Cover
AFS photo
Manure Presence
Score only if livestock and/or human waste discharge is present
Manure Presence
Riffle Embeddedness
Score only if riffles are present, a naturally occurring alluvial feature, or known to be buried.
Riffle Embeddedness
K. Gullett photo
Macroinvertebrates Observed
Macroinvertebrates Observed
Group IMayfly-
Ephemeroptera(collector)
Group IStonefly-Plecoptera
(Shredder)
Group IICrayfish-
Crustacean
Group IIDragon Fly
Group IIIMidge Fly Larvae
Summary
• Assess stream reach 12 X bankfull width• Score a maximum 15 elements; use those
applicable to your site• Assign a rating for each element—
intermediate scoring is OK• Calculate overall score• Determine the narrative rating• Describe potential causes of poor conditions
and recommendations for improving them
Identify Reaches to be evaluated
East Branch Of The North River Rapid Habitat Assessment Summary
of Six Reaches Sampled 9-20-2004
-1
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
PR1 DSPR2 PR3DS PR6 PR7B PR7AReach Id
Co
nd
itio
n R
atin
g(2
0-16
Ref
eren
ce,
15-1
1 G
oo
d,
10-6
Fai
r, 5
-0 P
oo
r)
Epifaunal Substrate and Available Cover EmbeddednessVelocity/Depth patterns Sediment DepositionChannel Flow Status Channel Alteration Frequency of Riffles/Steps Bank Stability-left bankBank Stability-right bank Bank Vegetative Protection-left bankBank Vegetative Protection-right bank Riparian Zone Width-left bankRiparian Zone Width-right bank
Reference-Optimal
Poor
Good
Fair
Rapid Aquatic Habitat Assesment Total Score Based Upon Ten Aquatic Habitat Variables at Six Reaches of the East Branch of the North River
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
PR1 DSPR2 PR3DS PR6 PR7B PR7A
Reach Identifier
To
tal A
sses
smen
t S
core
(0.
00 t
o 1
.00)
Poor
Good
Fair
Courtesy of Buckley and Nixon(2001) An Historical Assessment of Anadromous Fish in the Blackstone River
In 1735 The RI General Assembly stated that any mill owner erecting a dam across a water where migratory fish normally pass had to provide a “good and sufficient Way through such Dam or Weir for the fish to pass and repass” that be opened during the spring runs…., “