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UPDATES TO THE 2005 PUGET SOUND CHINOOK RECOVERY PLAN
Woody Debris Target Update of the Stillaguamish Chinook Recovery Plan
Produced by: The Stillaguamish Technical Advisory Group, a subcommittee of the SWC
2/8/2016
Version 1.0
2
Adaptive Management of Woody Debris - Target Update Objectives
1. Adapt wood target quantities for near-term implementation (10 years) and for desired future
condition (natural and constructed wood quantities).
2. Review and consider woody debris reference values from literature to create condition bins (i.e.;
Poor, Fair, Good, Best).
3. Develop monitoring objectives that support information needs to describe woody debris status,
changes and implementation progress over time.
The revised woody debris targets are developed around the following information categories and can be
reviewed at a regular time interval;
What – Woody debris target definitions and descriptions,
Where – Priority locations for wood placement implementation,
Why – Addresses key functions and river process that have been altered and affected by
historical loss of wood,
How – Project and placement types expected to have high performance,
How much – Wood quantity by location that leads to a Desired Future Condition.
Adaptive Management is future decision-making informed by baseline conditions, documented change,
progress relative to goals, new science-based information, and new alternatives for action that
eventually lead to Desired Future Conditions. The wood target will be adjusted every 10 years depending
on total wood and or wood jam abundance (and functions) of constructed and natural wood
components. Hypothetically, if natural jam count declines, then the constructed jam target (and level of
effort) would be increased. If natural jam abundance raises the total jam count toward the desired
future condition, then the constructed jam target eventually might be less. This is known as the wood
budget to achieve desired future conditions and will be managed adaptively by collecting and applying
future monitoring information.
The following table highlights the woody debris target objectives described by the current plan (SIRC
2005) and the proposed targets for the second 10-year salmon recovery period (2016-2025). These
proposed targets are recommended by the Stillaguamish TAG for approval by the Stillaguamish
Watershed Council.
3
Table 1. TAG Recommendation to SWC for proposed updated LWD Target.
WOODY DEBRIS
TARGET –
PROJECT IMPLEMENTATION TARGET FOR 2ND 10-YEAR SALMON RECOVERY
PERIOD (2016-2025)
CATEGORY/
CRITERIA CURRENT PROPOSED
Locations for LWD
placement
NF/SF NF/SF/Mainstem/Pilchuck Cr./Jim Cr./Squire
Cr./Boulder/French/Deer.
Type Build engineered log
jams with 40 to 60 large
wood pieces per jam.
ELJs according to site specific design criteria.
Flood Fences that may form future in-channel log jams.
Quantity 51 jams in 10 years (62
jams in 50 years;
baseline year is 2005).
122 jams in 10 years (2016-2025); See Table 4 and Map
4.
Targets Number of “approved”
jams vary among 7
reaches in NF/SF (Plan
page 97).
Number of jams vary among 16 target reaches (see
Tables 3 and 4) as either 2, 4, or 8 jams/km.
Priority locations Near high Chinook use
areas in 1st/2nd priority
areas (Figure 20 in Plan,
page 108).
Map 4.
Effective functions Pool formation, side
channels engagement,
fish cover, roughness,
flow routing.
Pool formation, side channels engagement, fish cover,
roughness, flow routing, hyporheic exchange,
temperature diversity.
Progress needed 5 ELJs/yr.; evaluate in
Year 3 and 7 of first 10
years (2014).
12 wood installations/year; Evaluate in year 3 and year 7
of 2nd 10 years (2016-2025).
Limitations/
Uncertainty
Risk, feasibility, hazard
management.
Risk, feasibility, hazard management; Also, uncertain
linkage between Corridor Acquisition Plan, River Reach
Assessments, and importance or sequence with respect
to other Plan targets.
4
Implementation
monitoring
Count ELJs w/ 40
pieces.
Count LWD key pieces meeting NMFS criteria as part of
wood jam or flood fence construction; Count all other
smaller pieces used for construction that contribute to
wood jams.
Effectiveness Placement of wood is
increasing habitat (≥5%
pool area [primary &
backwater], pool
frequency) within 5
years.
Placement of wood is increasing habitat (same as left)
within 5 years. Other effectiveness or performance
determined by project objectives related to site scour,
cover, bank protection, forested island protection, flow
routing, cool water refuge creation, material storage
(wood/sediment). Each project must document pre-
project habitat conditions.
Monitoring/
Reporting
frequency
Annual count; 3-4 yr.
analysis period.
Annual count of wood installations and piece inventory
(as built info); 3-4 yr. analysis period for
implementation; 5 year effectiveness monitoring
frequency from time of installation – Use pre-project
data for evaluating habitat change.
Adaptive
Management
action
<5% increase in pool
area in 5 years;
annualized ELJ totals
do not meet target.
<5% increase in jam-formed pool area in 5 years;
annualized ELJ totals do not meet target.
WOODY DEBRIS
TARGET –
DESIRED FUTURE CONDITIONS
CATEGORY/
CRITERIA
CURRENT PROPOSED
Piece quantity 80 pieces/mile (= 50
pieces/km).
80 pieces/mile (= 50 pieces/km) for channel >40
meters bankfull width; Other piece quantities for
smaller channels are based on Fox 2001.
Piece size criteria 50 ft length; 24 inches
diameter; No channel
size applicability (also
15 m length and 60 cm
diameter).
Key pieces are 50 ft. length; 24 inches diameter (or 15
m length and 60 cm diameter); LWD is at least 30 ft.
length and 12 inches diameter (or 7.6 m length and 30
cm diameter (USFS 1998)). Small wood is at least 2 m
length and 10 cm diameter (WFPB 2011).
5
Literature sources NMFS 1996 (aka
“Matrix of Pathways
and Indicators”).
NMFS 1996 (aka “Matrix of Pathways and Indicators”);
USFS 1998; Fox 2001 or Fox and Bolton 2007.
Total Jam quantity
(natural & ELJs)
None. Varies by reach as either 2, 4, or 8 jams/km. Total is
1,274 jams from Table 3.
Jam criteria At least 3 pieces LWD. At least 3 key pieces LWD that touch each other with
minimum piece dimensions of 7.6 m length and 30 cm
diameter (Haas et al. 2003).
NOTE: Other criteria for wood jams include 10 pieces
(small wood criteria; WFPB 2011); 30 pieces (NOAA
2015) or 100 m2 wood jam area (NOAA 2015). These
criteria are not consistent with wood jam data
collection in Stillaguamish watershed since 2002.
Status and trend
monitoring
Every 10 years do full
wood inventory.
A wood inventory will be implemented every 10 years;
Census in NF/SF/Mainstem; Repeat sample reaches in
Pilchuck, Jim, Squire, Canyon, Upper SF, Boulder, Deer,
Rollins, Grant, French every 10 years.
Reporting
frequency
None. Every 10 years; prior to wood target adaptive
management and regional population status review.
Report updated LWD quantities and characteristics by
survey reaches (e.g. Leonetti et al. 2015).
Adaptive
Management
action
None. Revise jam implementation target quantities based on
updated key piece deficit estimates, new ELJ jams, and
natural jams compared to wood jams targets (by
reach) and relative progress among priority locations
and individual reaches.
Desired Future Condition – the desired future condition as a target is based on the recognition that a
more properly functioning quantity of woody debris, closer to regional reference conditions, will form
more pool habitats (some of which will be new cool water refuges), provide fish cover, retain gravel
bars, shield forested islands in floodplains, create more flow pathways, improve cooling through
hyporheic exchange and increase sinuosity, side channels, and backwater edge habitats. Indicators of
wood debris recovery therefore will not only be based on the quantity of placed wood, but also based
on the weight of evidence presented by an increase in the following;
Natural woody debris jams and wood loading,
6
Pool count and pool frequency,
Wood-formed pools,
Pool habitat cover,
Gravel bar storage at wood jams,
Flow pathways at bankfull elevation,
Channel migration leading to greater sinuosity,
Backwater edge habitat,
Forest cover in a more natural river corridor, and
A reduction in river bank armoring.
These descriptions of future improvements in the status of conditions can all be monitored with
relatively simple indicators, collected at relatively low cost, with high precision, at time intervals to
support on-going salmon recovery information needs and adaptive decision-making.
Existing Conditions
Existing conditions are described in Table 2 using condition category bins (i.e., poor, fair, good, best).
These categories reflect quartiles of reference condition (an un-managed western Washington forest)
based on Fox (2001) for key pieces of woody debris as defined by NMFS (1996). Table 2 reports the
average number of woody debris jams observed by survey sites (2000-2011) based on total wood
quantity defined by both the NMFS key piece criterion and the Washington Forest Practices Board
(2011) watershed analysis manual. The simplified wood jam target (jams/km) by reference condition
category is proposed in the last column.
Table 2. Existing conditions. Observed jam frequency when total wood quantity by site meets poor, fair,
good, or best quantity categories based on reference conditions (Fox 2001).
Average jams/km by category for…
Category
Percentile of
reference
conditions
…NMFS Key Piece
quantity
…WFPB total
wood quantity*
Range
(jams/km)
Target
(jams/km)
for Table 3
Poor 0-25th percentile 1 .7 (23 sites) 1 .6 (19 sites) 0-2.5 2
Fair 25-50th percentile 3.2 (6 sites) 3.4 (4 sites) 2.5-4.9 4
Good 50-75th percentile 8.7 (3 sites) 4.5 (3 sites) 4.9-7.2 Combined
7
Best >75th percentile 7.5 (2 site) 9 (3 sites) 7.2-15 below
Good/Best >50th percentile 8.5 (5 sites) 7 (6 sites) 4.9-15 8
* Site totals are less than previous column because small wood was not measured in 2000/2001.
NMFS Key Pieces are each >15 m length and at least 60 cm diameter (NMFS 1996)
TFW/WFPB wood pieces are >2 m length and 10 cm diameter (WFPB 2011)
Figure 1 highlights the current count of survey sites for each condition category. More than 80% of
survey sites are in the poor or fair categories. Even in un-managed reference forest conditions, woody
debris quantity may be low (Fox 2001). However, a poor category of wood quantity based on reference
conditions generally should only reflect the 25th percentile distribution of the reference range. This
wood target proposal for the Stillaguamish suggests that no more than 25 percent of survey sites should
be in a poor condition category – the 25th percentile of our data distribution. Figure 1 also highlights a
proposed future frequency (count) of survey sites that would meet the desired future condition (DFC)
for wood jam quantity per kilometer stream length.
Figure 1. Count of reaches that fit condition categories based on existing condition and proposed
desired future condition.
Using this conceptual distribution of survey sites meeting Desired Future Conditions, actual assignments
of future site performance (poor, fair, good, best) were proposed for river and stream locations
overlapping the Chinook salmon spatial distribution. In Table 3, the proposed desired future condition
(DFC Jams/km column) is shown alongside of each river or stream reach location and the existing
8
performance category compared to existing conditions for the same reaches. The quantities are based
on the performance targets for individual reaches portrayed in Table 3. Proposed reaches that meet the
poor performance category are those that are currently heavily altered or geomorphically (based on
slope and channel confinement) would naturally have lower wood quantity (Fox 2001). Finally, the
estimated count of future wood jams (constructed and natural) is listed. It is worth highlighting that
even though the mainstem Stillaguamish River may have a poor wood performance assignment into the
future, the proposed 69 wood jams (Table 3) is 57 jams more than the current condition (based on 2002
data; Haas et al. 2003).
This proposal recommends that the implementation target for wood placement projects is 20% of the
estimated wood deficit or 122 wood jams (Table 4). This total is equally apportioned over all selected
reaches (Table 4), but this proposal recommends that the wood target should be implemented based on
priority locations. These locations are shown in Map 1. For example, the jam implementation target
proposed for the Upper North Fork Stillaguamish River (18 jams) reflects the large effort already made
to implement the original Plan target. As of 2015, 26 large wood jams have been constructed in the
North Fork Stillaguamish River, including woods jams built in 1998. Elsewhere, seven other wood jam
projects have been constructed toward the implementation target.
This implementation target will be applicable over the next 10 years and is greater than the original plan
target due to two factors. First, this revised wood target includes more locations for implementation
than the original plan. Second, the quantity of woody debris has decreased in the North Fork
Stillaguamish River between 2002 and 2011 (Leonetti et al. 2015), necessitating an increase in the
quantity of constructed jams or other wood placement. The proposed target, if implemented over ten
years, amounts to annualized progress of 12 constructed jams per year, which more than doubles the
current annualized rate of progress. Thus, although the 20% implementation target is somewhat
arbitrary in terms of the direct linkage to fish responses and population performance, the amount of
proposed implementation is large and will test the capacity of watershed stakeholders, more so than in
the first 10 years of Salmon Recovery Plan implementation.
9
Table 3. Existing wood condition category by site according to Table 2 and desired future condition (2, 4,
or 8 jams/km). The final column is the desired future jam count based on condition assignment.
10
Area
Ecosystem
component
Reach/ Existing
Category DFC Jams/km
Point estimate of
DFC jam total
CS1
HS1
MS1
MS3
MS4AMS4B
NF 1 2 8
NF2 8 90
NF3 8 70
NF4* 2 10NF5* 8 40
NF6 8 54
NF7 8 39
Small channel NF8 8 48
SF1 8 57
SF2 4 26
SF3 4 50
Upper SF 6,8 (DG) 8 182
SF 7** 8 37
Pilchuck 1 8 52
Pilchuck 2 8 38
Jim 1 2 13
Jim 2 4 29
Jim 3 4 14
Jim 4 8 77
Lower Deer (DG) 4 11
Boulder 1 8
Boulder 2 4
Squire 1 8
Squire 2 8
French 1 4
French 2 8
Canyon 1 8 87
Canyon 2 8 46
Rollins 4 6
Grant 4 9
Small channel
Small channel
Large channel/ side
channels
Large channel/ side
channels
* Parts of N4 and N5 include the confined and steeper river reach downstream from the 2014 Oso slide.
This length is excluded from NF 4 and NF5. ** Only unconfined portion of SF7.
29
32
Mainstem 2 69
Lower North Fork
Upper North Fork
Lower South Fork
Large channel/ side
channels
Large channel/ side
channels
Large channel/ side
channels
Upper South Fork
Pilchuck Creek
Other Small channel
Jim Creek
51
*DFC - Desired Future Condition
11
Table 4. Wood piece and jams deficit by area/reaches and proposed 10-year implementation target for priority reaches. The total (122 jams) is
based on implementation of 20 percent of the jam deficit (609 jams). Note: not all locations from Table 3 are included in the totals below.
Area/R
eaches
Main
stem
Low
er NF
Upper NF
Low
er SF
Upper SF7
Pilchuck
1
Upper SF 6
,8
Pilchuck
2
Jim 1
/2
Jim 3
/4
DeerBould
er 1
Boulder 2
Squire 1
/2
French
1
Rollins
Grant
Total
Area/R
eaches
Current Plan Priority √ √ √
NMFS
Pieces -1765 -1504 -850 -1329 -220 -38 DG -27 -44 -51 DG 0 -9 -31 -3 -5 -11 -5887
Jams -
"custom" 57 168 91 104 30 30 Unk 25 24 22 Unk 0 9 37 3 5 4 609
ADAPTIVE 10-YEAR WOOD IMPLEMENTATION TARGET ALTERNATIVES AS OF 2015 - Anticipated to be reviewed in 2025.
Wood target objective
Jam deficit "custom" is based on jam frequency assignments to reaches as in Table 3 (2, 4, or 8 jams/km).
Deficit
Main
stem
Low
er NF
Upper NF
Low
er SF
Upper SF7
Pilchuck
1
Upper SF 6
,8
Pilchuck
2
Jim 1
/2
Jim 3
/4
DeerBould
er 1
Boulder 2
Squire 1
/2
French
Rollins
Grant
Total
Wood target objective
11 34 18 21 6 6 NA 5 5 4 NA NA 2 7 1 1 1 122
Green = Priority 1 area as in Map 4
Orange = Priority 2 area as in Map 4
Other locations are non-priority areas for near-term implementation
20% of DFC Deficit
12
Map 1. Wood implementation priority reaches.
1
References
Fox, M.J. 2001. A new look at the quantities and volumes of instream wood in forested basins within
Washington State. Masters Thesis. University of Washington, Seattle WA.
Fox, M.J. & Bolton, S. (2007). A regional and geomorphic reference for quantities and volumes of
instream wood in unmanaged forested basins of Washington State. North American Journal of Fisheries
Management, 27, 342–359.
Haas, A.D., Leonetti, F.E., Parker, L.T., Purser, M.D., & Rustay, M.D. (2003). Stillaguamish river bank and
physical habitat conditions survey 2002 summary report. Everett, WA: Snohomish County Public Works
Surface Water Management.
Leonetti, F.E., Rustay, M.D., Tran, T., & Purser, M.D. (2015). 2011 North Fork Stillaguamish River Habitat
Inventory and Assessment of Change since 2002. Snohomish County Public Works, Surface Water
Management. Everett, WA.
National Marine Fisheries Service (NMFS). (1996). Coastal salmon conservation: Working guidance for
comprehensive salmon Restoration initiatives on the Pacific Coast: Appendix II: Making endangered
species act determinations of effect for individual or grouped actions at the watershed Scale. Portland,
OR: NMFS.
Stillaguamish Implementation Review Committee (SIRC). (2005). Stillaguamish watershed Chinook
salmon recovery plan. Retrieved from
http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CB4QFjAA&url=http%3A
%2F%2Fwww.stillaguamish.nsn.us%2FPublish%2FStillaguamish%2520Watershed%2520Salmon%2520Re
covery%2520Plan%2520--%2520Jun.pdf&ei=Fc9sVe--
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USDA-Forest Service. (1998). Stream inventory handbook: Level I & II. USDA, Region 6, Version 9.8.
Washington Forest Practices Board (2011). Standard Methodology for Conducting Watershed Analysis -
Board Manual. Version 5. Washington Department of Natural Resources, Olympia, WA.