development of a function-based stream assessment...
TRANSCRIPT
Development of a Function-based Stream
Assessment Methodology
ESA
Skidmore Restoration Consulting
Prepared for:
Willamette Partnership
US EPA
ODSL
US Army Corps
Contact Information for Project Details
Core Project Team • Tracie Nadeau, EPA Region 10
• Dana Hicks, Oregon Department of State Lands
• Judy Linton, US Army Corps of Engineers
• Nicole Maness, Willamette Partnership
Assessment Consultants
• Nicole Czarnomski, ESA
• Peter Skidmore, Skidmore Restoration Consulting
Framework Consultants
• Peter Skidmore, Skidmore Restoration Consulting
• Greg Koonce, Inter-Fluve
A Watershed-Based Approach
to Mitigation in Oregon
Compensatory mitigation decision-making
in a watershed context
Replace loss of functions due to
unavoidable impacts to all aquatic
resources
Use of function or condition assessment
to determine compensatory mitigation
Consistent requirements for all forms of
mitigation (banks, ILF, permitee-
responsible)
Final Compensatory Mitigation Rule (2008)
A Watershed-Based Approach
to Mitigation in Oregon Oregon Removal-Fill Program Rule (2009)
Specified non-wetland compensatory
mitigation required for unavoidable
impacts, and must be commensurate with
impacts
Expanded mitigation statutes to “waters of
the state”, where previously it only
referred to “wetlands”
Requires mitigation offsetting losses of
functions and values
A Watershed-Based Approach
to Mitigation in Oregon
Improve environmental outcomes
Identify best opportunities
for successful mitigation
Improve regulatory transparency,
consistency, and timeliness
Anticipated Benefits
Wetlands
A Watershed-Based Approach
to Mitigation in Oregon
Assessment
Methodology
Program
Elements
Program
Policy
Stakeholder
Engagement
Agency &
Technical
Engagement
Implementation
Streams
Framework (2010 – 2011)
Assessment Method (2012 – 2014)
Develop Mitigation Program (ongoing)
Review existing methods and literature
Montana’s mitigation approach
Salmon Credit Calculator
Habitat Equivalency Analysis
Habitat Equivalency Procedure
ODFW Habitat Mitigation Policy
EDT
Streamflow Duration Assessment
Method for Oregon
National Context
Harman et al. 2012 (A Function-Based Framework for Stream Assessment and Restoration Projects)
Stream Functions
FUNCTIONAL GROUP FUNCTION
Hydrologic Functions Surface water storage
Sub/surface transfer
Flow variation
Geomorphic Functions Sediment continuity
Substrate mobility
Biological Functions Maintain biodiversity
Create habitat (aquatic/riparian)
Sustain trophic structure
Chemical and Nutrient
Functions
Nutrient cycling
Chemical regulation
Thermal regulation
Function attributes
ATT
RIB
UTE
Ove
rban
k Fl
ow
Eff
ecti
ve D
isch
arge
Bas
e Fl
ow
Gro
un
dw
ater
Flu
x B
ed M
ob
ility
Sed
imen
t Ch
arac
ter
Ban
k St
abili
ty H
ydra
ulic
Var
iab
ility
Str
eam
Hab
itat
Rip
Str
uct
ure
&
Co
mp
Aq
Sp
p St
ruct
ure
& C
om
p W
ater
Qu
alit
y W
ater
Tem
per
atu
re S
edim
enta
tio
n
FUNCTIONAL
GROUPFUNCTION
Surface water
storageX X
Sub/surface
transferX X X X
Flow variation X X X X X X X X
Sediment
continuityX X X X X X X
Substrate
mobilityX X X X X X X X
Maintain
biodiversityX X X X X
Create habitat
(aq/riparian)X X X X X X X X X X X
Sustain trophic
structureX X X X
Nutrient cycling X X X X
Chemical
regulationX
Thermal
regulationX X X X
Hydrologic
functions
Geomorphic
functions
Biological
functions
Chemical,
nutrient &
thermal
functions
Concluded there was need for:
Stream Classification System
Function-Based Assessment Methodology
Methodology Field Testing
Program Policy
Capacity Building/Outreach
Draft assessment framework (USEPA 2012)
Framework (2010 – 2011)
Assessment Method (2012 – 2014)
Develop Mitigation Program (ongoing)
Stream Function Assessment Methodology
Conceptual
Framework
Draft Functions,
Values & Measures
Field testing (wet/dry)
Draft Assessment
Methodology (tool & scores)
Final Assessment
Methodology
E x p e r t R e v i e w Stream Technical Working Group
2013
2012
2014
Functions-Attributes-Measures
Function Attribute Measure
Flow Variation Overbank
flow
Visual analysis for presence/absence of field indicators
Number days per year, and years per decade that flows
exceed the "bankfull flow".
Effective
Discharge
Annual frequency of flows exceed the "channel forming
flow".
Percent impervious area of contributing watershed
Surface
Water
Storage
Riparian
structure and
composition
Percent of historic/potential floodplain excluded by
levee:
Overbank
flow
Number days per year, and years per decade that flows
exceed the "bankfull flow".
Function-Attribute-Measures
Criteria for selecting measures
Science-based
Function-based
Rapid (2x2x2)
Repeatable
Applicable across all stream
types
Hydrology F1 How altered is the historical floodplain?
Hydrology F2 Have flow modifications altered base flow?
Biology F3 Are there non-native aquatic animal species present?
Biology F4 Are side channels present?
Biology F5 What is the BIBI family score?
Water Quality F6 What is # of d/y that stream temp > 20 degrees C?
Hydrology F7 Does stream interact with its geomorphic floodplain?
Hydrology F8 What is extent of floodplain inundation in recent past?
Geomorphology F9 Is channel bed erosion influencing floodplain interactions?
Geomorphology F10 Is large wood present within the active channel?
Geomorphology F11 Is channel creating & maintaining alluvial landforms?
Office/Field Questions – Stream Functions Stream Function Assessment Methodology
Geomorphology F12 Have channel banks been stabilized and/or armored?
Geomorphology F13 What is the overall condition of the channel banks?
Geomorphology F14 Does channel exhibit a range of typical bedforms?
Geomorphology F15 Does channel have the ability to migrate?
Biology F16 Evidence of resident/active beavers in assessment reach?
Biology F17 Ratio of average riparian buffer width to active channel
width through the assessment reach?
Biology F18 Are there invasive plants in riparian buffer?
Biology F19 Is there woody vegetation in riparian buffer?
Biology F20 Are mature trees in riparian buffer?
Biology F21 Are conifers in riparian buffer?
Biology F22 What is the variety of channel bed habitats available?
Office/Field Questions – Stream Functions Stream Function Assessment Methodology
Conceptual Framework
Stream Function -
the processes that create and support a stream ecosystem
Stream Value -
the ecological & societal benefits that riverine systems
provide
Stream Function Assessment Methodology
Context V1 Proximity to natural areas
Hydrology V2 Is there infrastructure (urban/rural residential areas, utilities)
in mapped floodplain that can be affected by flood waters?
Hydrology V3 Is there downstream flooding?
Hydrology V4 Does the project area have the capacity to store water that is not being stored in the contributing basin?
Hydrology V5 Are there withdrawals changing timing or volume of flow?
Hydrology V6 Are there impoundments changing timing or volume of flow?
Geomorphology V7 What is the land use of the contributing area?
Geomorphology V8 Problems with sedimentation? (303d list, TMDL)
Biology V9 Is project area within a priority watershed for anadromous fish or within a watershed that contains ESA listed species?
Biology V10 Are there rare non-anadromous fish?
Biology V11 Are there rare invertebrates?
Office/Field Questions – Stream Values Stream Function Assessment Methodology
Biology V12 Are there rare amphibians or reptiles?
Biology V13 Are there rare waterbirds?
Biology V14 Is this waterbird habitat?
Biology V15 Is this rare songbird, raptor, or mammal habitat?
Biology V16 Are there rare plants in the vicinity?
Biology V17 Are there fish passage barriers?
Biology V18 What is the % of intact riparian area of the contributing basin?
Biology V19 What is continuity of intact riparian area upstream (5x reach length)
and downstream (5x reach length) of project site?
Water Quality V20 Is reach on 303d list or other TMDL for nutrient impairment?
Water Quality V21 Is reach on 303d list or other TMDL for metals/other toxics
impairment?
Water Quality V22 Is reach on the 303d list or other TMDL for temp impairment?
Hydrology V23 Site have aquatic habitat features uncommon in contributing basin?
Office/Field Questions – Stream Values Stream Function Assessment Methodology
Context
Hydrologic Landscape Regions
Seasonality
Terrain
Soil Permeability
Aquifer Permeability
Wigington et al. (2012) ; Leibowitz et al. (2011)
Climate
Scale Parameter Classes Function/Process Represented Data Source
Local
(reach)
Stream Order 1-n Geomorphic character Strahler (synthetic)
Hydrologic Landscape (HL) Assessment unit classes as
generated
Statewide assessment unit
hydrologic classification; annual
climate, water surplus
seasonality, aquifer and soil
permeability, topography
Wigington et al. 2012; Oregon
Hydrologic Landscapes: a
Classification Framework
Erodibility Easily erodible
Moderately erodible
Difficult to erode
Sediment supply and delivery Bedrock geology maps (1:500K)
NOAA (Jordan/Volk)
Gradient <2%
2-6%
>6%
Geomorphic character EPA; 1:24,000 stream lines and
DEM; see Montgomery &
Buffington 1993
Floodplain Influenced Yes; >5% floodplain
No
Topography EPA; see Wigington et al. 2012
and Wolock et al. 2004; mid-
point calculation separating
‘floodplain’ and ‘plateau’ from
‘flat’ terrain class
Watershed
(integrated)
Annual Water Surplus
(how much water
available?; 30 yr average
annual surplus vol provided
as additional data layer)
No Surplus; <5%
Limited; 5-33%
Moderate; 34-66%
Extensive; 67-100%
Hydrologic processes EPA; area surplus (S) as
calculated for each integrated
watershed
Seasonality of Maximum
Surplus Release
(when is precipitation most
available?)
Fall-Winter; Oct-March
Spring-Summer; April - Sept
Hydrologic processes EPA; positive snow-melt
adjusted surplus (S*) as
calculated for each integrated
watershed
Terrain
(dominant terrain?)
Mountain
Transitional
Flat
Topography EPA; assesses local (HL)
terrain classes, and assigns
dominant terrain class to
integrated watershed
Floodplain Influenced Yes; >5% floodplain
No
Topography EPA; as per local floodplain
parameter, calculated for each
integrated watershed
Aquifer Permeability
(hydraulic conductivity; 3
data layers)
Low; <1.5 m/day
Medium; >1.5 and <3 m/day
High; >3 m/day
Watershed hydrology EPA (Wigington); as calculated
for each integrated watershed
Classification parameters, classes, and data sources (USEPA in prep)
L_STREAMORDER 1
L_AREA_KM 73.6587
L_CLIMATE Moist
L_SEASONALITY Spring
L_AQUIFER_PERM Moderate
L_TERRAIN Mountain
L_SOIL_PERM Moderate
L_HL_CLASS MsMMM
L_ERODE_CLASS Difficult to Erode
L_GRADIENT Low
L_FLOODPLAIN No
W_AREA_KM 73.659
W_TERRAIN Mountain
W_FLOODPLAIN No
W_SURPLUS Moderate
W_VOL_SURPLUS 1352730
W_SEASONALITY Spring
W_PC_L_PERM 39.76
W_PC_M_PERM 56.01
W_PC_H_PERM 4.23
Headwater reach
(USEPA in prep)
L_STREAMORDER 3
L_AREA_KM 116.3556
L_CLIMATE Semiarid
L_SEASONALITY Fall or Winter
L_AQUIFER_PERM Moderate
L_TERRAIN Mountain
L_SOIL_PERM Low
L_HL_CLASS SwMML
L_ERODE_CLASS Difficult to Erode
L_GRADIENT Low
L_FLOODPLAIN No
W_AREA_KM 1569.075
W_TERRAIN Mountain
W_FLOODPLAIN No
W_SURPLUS Limited
W_VOL_SURPLUS 22059132
W_SEASONALITY Fall Winter
W_PC_L_PERM 47.36
W_PC_M_PERM 45.42
W_PC_H_PERM 7.22
Downstream reach
(USEPA in prep)
US EPA Oregon Stream Classification
Covers 5420 stream reaches
Watershed-level data not calculated for watersheds with headwaters outside of Oregon (USEPA in prep)
Stream
Type
Str
ea
m T
yp
es
an
d C
las
s
Function
Measures
Value
Measures
Stream
Classification
Parameters
Function
Subscores
Value
Subscores
Site
Score
Relative
Importance:
Function Scores
Relative
Importance:
Value Scores
Stream Function Assessment Methodology
Field Testing
Objectives
“Accuracy” (vs BPJ)
Repeatability
Sensitivity
Usability
• ~60 Sites
• Wet & Dry Season
• Begin Summer 2013
Framework (2010 – 2011)
Assessment Method (2012 – 2014)
Develop Mitigation Program (ongoing)
MILESTONE STATUS
Stream Classification System Complete (internal
review)
Conceptual Assessment Methodology Complete
Draft Assessment Methodology (revisions ongoing) Complete
Method Field Testing (Wet/Dry Season) Begin Summer 2013
Final Assessment Methodology (v1.0) Summer 2014
Program Development Ongoing
Capacity Building/Outreach (internal/external) Ongoing
Stream Mitigation Framework Key Milestones
Developing policy options,
through a collaborative
process, for agency decision-
making.
PROGRAM ELEMENTS
Site Selection Criteria
Eligibility
Credit Quantification
QA/QC
Credit/debit accounting
Performance Standards
Monitoring Requirements
Verification
Service Areas
Compensatory Mitigation Framework Program Policy
Compensatory Mitigation Framework Capacity Building & Outreach
Wetlands Technical Working Group
Streams Technical Working Group
Agency & Stakeholder Training
Public Review