Queen Charlotte Islands Stream Rehabilitation Studies
A Review of Potential Techniques
by D.R. Bustard'
'Consultant
Smithers, B.C. VOJ 2N0
P.O. Box 2792
Canadian Cataloguing in Publication Data
Bustard, David R., 1950-
studies Queen Charlotte Islands stream rehabilitation
(Land management report, ISSN 0702-9861 ; no. 28)
Bibliography: p. ISBN 0-771 8-8463-X
1. Fish habitat improvement - British Columbia - Queen Charlotte Islands. 2. Stream conservation - British Columbia - Queen Charlotte Islands. 3. Mass-wasting - Environmental aspects - British Columbia - Queen Charlotte Islands. I. British Columbia. Ministry of Forests. II. Title. Ill. Series.
SH157.8.887 1985 639.9'77'0971 131 C85-092058-2
0 1984 Frovince of British Columbia Published by the Information Services Branch Ministry of Forests 1450 Government Street Victoria, B.C. V8W 3E7
Copies of this and other Ministry of Forests titles are available at a cost-recovery price from Queen's Printer Publications, Parliament Butldlngs. Victoria, B.C. V8V 4R6.
ABSTRACT
The po ten t i a l techniques fo r the rehab i l i ta t ion o f smal l streams which
have been degraded by mass wasting on the Queen Charlotte Islands are reviewed. Experience with possible rehabil i tat ion techniques i n other parts
o f the Pac i f i c Northwest i s summarized and suggestions on t h e i r a p p l i c a b i l i t y
for Queen Charlotte Islands streams are made. It i s stressed that stream
r e h a b i l i t a t i o n i s n o t an a l t e r n a t i v e t o sound habi tat protect ion. Stream
rehab i l i ta t ion shou ld be considered only after an assessment of the factors a c t u a l l y l i m i t i n g f i s h p r o d u c t i o n i s made. This report summarizes studies and
l i t e r a t u r e r e s u l t s t o t h e end o f 1981.
ACKNOWLEDGEMENTS
The author would l i k e t o acknowledge the co-operation of various staff
members of the B.C. F ish and W i l d l i f e Branch, the Canadian Department o f
Fisher ies and Oceans, and the In te rna t iona l Pac i f i c Salmon Commission f o r
providing valuable background information on stream rehab i l i t a t i on p ro jec ts
not documented i n t h e l i t e r a t u r e . As wel l , var ious s ta f f members of the U.S.
Forest Service, the U.S. Bureau of Land Management, the Washington State Department of Fisher ies, and the Washington State Department o f Natura l
Resources provided valuable information. Dr . Jim H a l l o f Oregon State
Univers i ty k ind ly made avai lab le draf t copies o f a number o f manuscript
reports which were very helpful. Dionys deleeuw, Pat Slaney, and Craig Wightman reviewed the f i n a l d r a f t o f t h e manuscript. The assistance o f
l i b r a r i a n Leigh-Ann Topfer of Envirocon Ltd. i s g r a t e f u l l y acknowledged.
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TABLE OF CONTENTS
ABSTRACT ............................................................... iii
ACKNOWLEDGEMENTS ....................................................... i v
1NTRODUCTION ........................................................... 1
THE STUDY AREA ......................................................... 1
BACKGROUND: POTENTIAL IMPACTS OF MASS WASTING ON THE STREAM
ENVIRONMENT .......................................................... 4
Debris Torrents .................................................... 4 Other Forms o f Mass Movements ...................................... 6
HEVIEW OF REHABILlTATION TECHNIQUES .................................... 7
Spawning Habitat ................................................... 8
Gravel cleaning ............................................. 8
Gravel Dlacement and catchment .............................. 13
Improved spawner access ..................................... 16
Side channel development .................................... 18
Incubation boxes ............................................ 18
Rearing Habitat .................................................... 19 In-stream structures ........................................ 19
Side channel and pond development ........................... 23
CONCLUSIOh ............................................................. 24
\
LITERATURE CITED ....................................................... 25
APPENDIX: PROPOSED REHABILITATION PROGRAM FOR 1982 .................... 29
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FIGURE
1. Location o f Queen Charlot te Islands................................. 3
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INTRODUCTION
Forestry and f i sh ing have t r a d i t i o n a l l y dominated the economy o f the Queen
Charlotte Islands. During the last decade the forest industry has expanded and some operations have s h i f t e d t o steep, less-stable terrain. As a resu l t ,
an accelerated ra te o f mass wasting has occurred i n steepland areas, and
considerable attention has focused on the impact of th is process on f i s h
streams i n the Queen Charlotte Islands. Fishery agencies have expressed continued concern that landslides caused by logging are degrading many small
but productive salmonid streams.
I n response to th is s i tuat ion, the F ish/Forest ry In teract ion Program (FFIP) was in i t i a ted t o research t he resu l t s o f mass wasting on the f i sh and
forest resources of the Queen Charlottes, and t o develop s t ra teg ies to
minimize these impacts. One aspect of th is appl ied research i s the assessment
o f techniques f o r r e h a b i l i t a t i n g streams tha t have been damaged by landslides.
Considerable experience with stream rehab i l i t a t i on has been acquired i n eastern North America during the past 50 years. Although stream r e h a b i l i t a t i o n i s r e l a t i v e l y new to f i shery b io log is ts in the fo res ted reg ions
of the Paci f ic Northwest, a number o f programs have been undertaken with varying degrees o f success. To take advantage of previous experience, the
f i r s t phase o f t he FFIP stream rehab i l i t a t i on program has been t o review past
e f f o r t s i n the Pac i f i c Northwest.
This paper includes a review o f t he ava i l ab le l i t e ra tu re and reports on some on-site examinations of stream rehab i l i t a t i on techniques used i n the Pac i f i c Northwest. Comments are made on t h e a p p l i c a b i l i t y of these techniques
t o Queen Charlotte lslands streams tha t have been af fected by mass wasting.
The repor t summarizes studies and l i t e r a t u r e t o t h e end o f 1981.
THE STUDY AREA
The Queen Charlotte Islands consist of approximately 150 i s lands l y i ng of f
the cen t ra l coas t o f Br i t i sh Columbia (Fig. 1). Two major islands, Graham and
Moresby, comprise most of the 9940 km of land mass. 2
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Nearly 200 streams con t r i bu te t o salmon spawning escapements averaging
more than 1 m i l l i o n f i s h a n n u a l l y (Canada Dep. Fisher ies and Oceans 1978 and 1979). The predominant salmon species based on stream escapement counts since
1947 are as follows:
Species % of escapement
Pink salmon (Oncorhynchus gorbuscha) 54
Chum salmon (Oncorhynchus keta) 35
Coho salmon (Oncorhynchus kisutch)
Sockeye salmon (Oncorhynchus nerka) 7
3 Chinook salmon (Oncorhynchus tshawytscha) 1
Coho salmon probably comprise a higher proport ion of the escapement than ind i ca ted , bu t a re d i f f i cu l t t o enumerate e f fec t i ve ly . Many streams o f t he Queen Charlot te Is lands possess populat ions of steelhead trout (Salmo
gairdner i ) , an increas ing ly rare and recreat ional ly valuable f ish. The
steelhead catch per day on the Queen Charlotte Islands has consistent ly been the second highest of the seven regions i n B r i t i s h Columbia (B.C. F ish and
W i l d l i f e Branch 1979-1980). Populations o f cu t th roa t t rou t (Salmo c l a r k i ) and
Do l ly Varden char (Salvelinus malma) are also present i n many streams.
Many streams on the Queen Char lo t te Is lands or ig inate i n steep headwater
areas tha t have some low-gradient areas suitable for spawning salmonids o f ten
res t r i c ted t o t he l owes t few kilometres. Coho and s tee lhead are typ ica l ly
distr ibuted throughout the accessible length of streams, while pink and chum
salmon generally concentrate i n the lowest sections, which sometimes consist
o f only a few hundred metres o f su i tab le spawning habi tat .
Most small streams on the Queen Charlotte Islands are subject t o h igh ly
variable discharges result ing from heavy r a i n f a l l and few headwater lakes t o moderate flows. Although streamflow data only e x i s t f o r two lake-headed
systems, an 800-fold dif ference between low sumner f lows and peak winter
freshets has been recorded. I n streams without lakes, discharge extremes are
undoubtedly greater, p a r t i c u l a r l y on the west coast where r a i n f a l l averages
over 400 cm annually.
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FIGURE 1. Location of Queen Charlotte Islands.
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BACKGROUND: POTENTIAL IMPACTS OF MASS WASTING ON THE STREAM ENVIRONMENT
Continuing studies on the Queen Charlotte Islands are assessing the
resu l t s o f mass wasting on the stream environment. Because these studies are
i n the early stages of development, resul ts are not avai lable. To provide
some background as t o why stream r e h a b i l i t a t i o n i s b e i n g considered, and i n
what d i rec t ion i t may be best oriented, a discussion of potential impacts i s
appropriate. This discussion i s prel iminary and speculative, and r e l i e s on
some f ie ld observat ions made i n conjunction with the 1981 stream studies and
on information derived from investigations elsewhere.
Mass wasting can be separated i n t o two categories useful for discussing
in-streams impacts: 1) debris torrents; and 2) a l l other mass movements such as debris sliaes, avalanches and flows, and slumps and earthflows as described by Swanston (1980).
Debris Torrents
Oebris torrents have the most v i s i b l e impact on streams i n the Queen
Charlottes. Although they generally occur i n the steeper gradient
i n te rm i t ten t channels and often terminate near the upper extent of
anadromous f i sh hab i ta t , some debr is torrents do move through anadromous
f i s h h a b i t a t (e.g. MacMillan Creek, Thurston Harbour Creek). The i n i t i a l
s l u r r y o f water and associated debris commonly entrains large quant i t ies
o f add i t iona l mater ia l from the steambed and banks. As the to r ren t moves
downstream, extensive areas of channel may be scoured t o bedrock and a
large matr ix of debr is and sediment i s deposited a t t he base o f the
tor rent . Veloc i t ies o f debr is tor rents , est imated to be up to severa l
tens of metres per second, are known only from a few spoken and wr i t t en
accounts (Swanston 1980). Although debr is tor rents pose s ign i f i can t
hazards t o anadromous f ish habi ta t , they have received l i t t l e study.
A to r ren t moving through a stream channel can r e s u l t i n massive
s h i f t i n g o f t h e streambed material, crushing and displacing eggs, alevins,
aquatic organisms, and juveni le f ish. Aside from the immediate impacts o f
the event, probable long-term impacts of debris torrents include the
fol lowing:
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1. In-stream debris i s r e d i s t r i b u t e d f o l l o w i n g a debr is torrent, and t y p i c a l l y accumulates i n the run-out zone o f t he t o r ren t or high on
the streambanks. Stable in-stream debris provides bed s t a b i l i t y i n stream channels (Swanson and Lienkaemper 1975). Pools formerly
developed around accumulations of debr is will be replaced by r i f f l e s ,
lead ing to a net increase i n r i f f l e areas and generally a loss i n stream rearing capabil i ty (Bryant 1980). Lower juveni le coho
standing crop has been shown t o be strongly correlated with decreased
pool volume (Nichelson and Hafele 1978). Debris destabi l ized by a to r ren t will continue to be mobile at high discharges and contr ibute
t o continued bed scouring and bank erosion problems.
2. Accumulations of debr is at the lower end o f a to r ren t may be up t o
6 m high and are usual ly barr iers to f ish movement upstream. These
debris accumulations can t rap bedload mater ia l resul t ing i n a
def ic iency of spawning gravels downstream (e.g. Showmar Creek).
3 . Water temperatures during low summer flows may exceed 20°C due t o an
absence of vegetation along a torrented creek.
4. Coarse bed mater ia l may accumulate i n a channel incapable of moving
it. This aggradation of material results i n a widened channel with fewer pools (L is le 1981) and low summer flows may become e n t i r e l y subsurface (e.g. Richardson Creek). Bed materials are most l i k e l y t o
accumulate i n the downstream low gradient section of a stream, which
generally has l e s s a b i l i t y t o move introduced material.
5. A debris torrented stream may experience a subsequent i n p u t o f s i l t
from material stored i n the channel and from scoured streambanks due
to surface erosion and small-scale slumping and sloughing (Swanson et - al. 1,076).
6. A short-term and possible long-term reduction i n the benthic fauna.
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A number of studies have reviewed t h e detrimental impacts of sediments on the spawning and rearing environments of salmonids ( P h i l l i p s 1971; Slaney " et a l . 1977; Bjornn " et a l . 1977; Cederholm and Salo 1979).
Many streams affected by mass wasting on t h e Queen Char lo t tes a re r e l a t i v e l y steep, high-energy systems, and may be capable of moving t h e finer sediment materials through the system quite rapidly. Cederholm and Sal0 (1979) found t h a t a stream system with a 2-4% gradient and a high maximum-minimum flow r a t i o (400-5OO:l) had t h e a b i l i t y t o f l u s h sediments caused by lands l ides . However, a low gradient system (14%) character ized by heavy accumulations of large organic debr i s retained sediments in t h e spawning g rave l s fo r a much g rea t e r time. Experience a t Carnation Creek has shown t h a t t h e sand component is accumulating i n the spawning grave ls i n t h e lower 2 km of the creek (Scrivener and Brownlee 1981).
Other Forms of Mass Movements The impacts of other types o f mass wasting occurring adjacent to a
stream channel depend on the nature , volume, and r a t e that ma te r i a l s a r e introduced and t h e capabi l i ty o f a s t ream to move them through t h e system. Slumps and ea r th f lows a r e fo r t h e most p a r t slow moving, and provide a continuous long-term source of sediment to the channel. Debris avalanches and debr i s f lows are rap id shallow mass movements that develop on steep hillsides and genera l ly cont r ibu te 60% or more of their i n i t i a l f a i l u r e volume almost immediately t o the channel (Swanston 1980).
Debris avalanches and flows into streams may result i n channel a l t e r a t i o n , a r ap id i nc rease i n bed and suspended loads, s i l ta t ion of
grave ls , and p a r t i a l or complete blocking of t h e stream channel through debr i s jam formation. Studies on Maybeso Creek, Alaska, indicate that l a r g e f l o a t a b l e deb r i s commonly des tab i l ized ex is t ing na tu ra l accumulations o f debr i s and eventual ly resulted i n fewer debr i s accumulations (Bryant 1980).
I n summary, deb r i s t o r r e n t s and other forms of mass wasting probably a f fec t bo th the spawning and r ea r ing capab i l i t i e s o f the stream system i n a va r i e ty of ways. Aside from the event itself which may be ca tas t rophic t o the stream ecosystem, longer-term impacts can include a de t e r io ra t ion
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i n g r a v e l q u a l i t y and s t a b i l i t y and a l o s s of access t o spawning areas. A reduct ion in juveni le rear ing habi ta t may result from a r ed i s t r ibu t ion of la rge o rganic debris i n the stream and from changes i n the channel c h a r a c t e r i s t i c s , which may lead t o less pool habitat and greater subsurface flows - a c r i t i c a l f a c t o r d u r i n g the la te summer low-flow period.
REVIEW OF REHABILITATION TECHNIQUES
In its strictest sense, s t ream rehabi l i ta t ion refers to r epa i r o f abused o r d e t e r i o r a t e d h a b i t a t t o speed up natural recovery. Stream enhancement refers t o t h e c rea t ion of a g rea t e r amount of su i t ab le hab i t a t t han would occur na tura l ly in a stream. In t h i s report , d iscussions will incorporate some small enhancement schemes wi th s t ream rehabi l i ta t ion , s ince t h e separat ion of the two is i l l o g i c a l i n p l a n s f o r the r e s to ra t ion of damaged hab i t a t .
This review of r e h a b i l i t a t i o n studies benefi ted from ava i l ab i l i t y o f two recent extensive reviews of the l i t e r a t u r e and cur ren t f i e ld appl ica t ions conducted by Hall and Baker (1982) i n Oregon, and Reeves and Roelofs (1982) i n northern Cal i fornia . As well, seve ra l reviews of techniques that can be used i n the r e s to ra t ion of streams have been prepared i n British Columbia (Parkinson and Slaney 1975; Canada Dep. Fish. and Oceans and B.C. Min. Environ. 1980).
The appl ica t ion of techniques suitable f o r use i n stream r e h a b i l i t a t i o n is rapidly evolving in t he Pacific Northwest, p a r t i c u l a r l y i n Oregon and Cal i forn ia where there has been a s h i f t i n emphasis from a r t i f i c i a l enhancement to res tora t ion of in -s t ream structures designed t o f a c i l i t a t e natural reproduction of wild s tocks. As Hall and Baker (1982) point out , many p ro jec t s have not been adequately documented, and those tha t have been o f t en lack an adequate design to provide an accurate assessment of t h e outcome. Few unsuccessfu l p ro jec ts a re repor ted in the l i t e r a t u r e , and va luable l essons to be learned from these fai lures are usual ly not shared.
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I t i s essent ia l that a r e h a b i l i t a t i o n program not be i n i t i a t e d u n t i l
f a c t o r s l i m i t i n g p r o d u c t i o n i n a given stream have been i d e n t i f i e d and evaluated. I f salmonid production i n a stream i s l i m i t e d by rearing, nothing
i s t o be gained by enhancing spawning habi ta t . For coho and steelhead, the avai labi l i ty of rear ing habi tat i s usual ly the
main factor inf luencing production, and habi ta t improvement ef for ts should be
aimed at improving sui table rear ing areas. It i s important to recognize which
phase o f r e a r i n g i s l i m i t i n g . For example, Mason (1976) found that despi te
increasing the summer carry ing capaci ty of coho i n a small Vancouver Is land
stream s i x - t o seven-fold, the benefits were o f f se t by the natural carry ing
capaci ty l imi ta t ions o f the stream over winter. Other species such as chum
and pink salmon enter the ocean as fry with l i t t l e or no freshwater rearing, and improvements t o spawning habi ta t will be most benef ic ia l (Canada Dep. Fish. and Oceans and B. C. Min. Environ. 1980).
I n th is rev iew, po ten t ia l rehab i l i ta t ion techniques have been separated
i n t o two' categories: 1) those designed t o r e h a b i l i t a t e spawning habi tat ; and 2) those fo r j uven i l e rea r ing hab i ta t rehab i l i t a t i on . I n some cases, the same
technique can be valuable for both spawning and rear ing habi ta t restorat ion.
Spawning Habitat Spawning hab i ta t rehab i l i ta t ion inc ludes the fo l low ing op t ions : 1 )
gravel cleaning; 2) spawning gravel placement and catchment; 3) the
prov is ion o f access fo r adu l t spawners above bar r ie rs ; 4) side channel
development; and 5 ) the use of incubat ion boxes.
Gravel cleaning
During the past 15 years a v a r i e t y o f e f f o r t s have been undertaken i n the Pac i f i c Northwest t o remove sediments accumulated
i n spawning gravels. These include techniques to d is lodge f ine
sediment from gravels, such as bul ldozers and f i r e pumps, or more
elaborate systems involv ing large t racked vehic les wi th v ibrat ing buckets or hydraul ic je ts .
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Bulldozers and gradalls: Gravel cleaning by bulldozer i s generally performed a t h igh
discharges when eggs and alevins are not present. A t the Meadow
Creek Kokanee Spawning Channel on Kootenay Lake, sca r i f i ca t i on o f t he
channel i s usual ly done i n ear ly August, p r i o r t o t h e annual spawning
run. E f f o r t s a r e l i m i t e d t o downstream s i t e s i n a watershed to avo id further degradation of spawning gravels below the area of cleaning.
The use o f heavy equipment precludes these kinds of operations i n small streams with abundant accumulations of large organic debris,
t y p i c a l o f streams on the Queen Charlotte Islands. As well, r ehab i l i t a t i ng spawning habi ta t with a bul ldozer has been successful
only af ter the source of f i n e sediments has been s tab i l i zed or eliminated (Reeves and Roelofs 1982).
The Washington State Department o f F isher ies (WSDF) has undertaken a number o f gravel cleaning programs with the use o f a
bulldozer. Included among the areas cleaned was one downstream o f a landsl ide on the Dungeness River (Heiser 1972) and some on the Cedar
and Sti l laquamish Rivers. Dick Al len (WSDF, personal corrmunication)
ind icates that although these operations were undertaken without
adequate design for subsequent evaluation, the streams appeared t o
r e t u r n t o a degraded condi t ion wi th in a single storm event. The WSDF no longer uses bulldozers t o clean gravel. I n B r i t i s h Columbia, bul ldozers have been used to c lean spawning gravel i n speci f ic
s i tua t ions such as i n the Meadow Creek spawning channel (C. Wightman, B. C. F ish and Wi ld i fe Branch [BCFW] , personal communication) and i n the Qualicum River (a controlled-flow system).
A g rada l l with a 2.1-m wide bucket modified by the add i t ion o f a
v ib ra to r and a screened bottom has been used to c lean gravel i n the Nadina River, a sockeye spawning r i v e r i n nor thwest Br i t ish Columbia (Andrew 1981). Gravel i s dug from the streambed with t h i s bucket,
which is then dipped i n and out o f the water while being vibrated,
causing the f ines t o drop through the screen and in to the ho le i n the streambed. The cleaned material i s then spread on top i n a layer
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approximately 30 cm deep. Although the Nadina i s lake-headed and
car r ies a re la t i ve l y sma l l sediment load, cleaned gravel was
gradually recontaminated with f ines. The In te rna t iona l Pac i f i c
Salmon Commission (IPSC) i s no longer conducting gravel cleaning
operations i n r i v e r s due to the short- term benef i ts der ived from cleaning and the downstream adverse e f f e c t s o f sediment (F. Andrew,
IPSC, personal communication). However, i n an emergency where
upslope s i l t a t i o n had been control led, the gradal l with a mounted
vibrat ing bucket could be a feasible gravel c leaning technique.
Manual techniques: Manual techniques, such as the use of f i r e pumps and hoses, are
r e s t r i c t e d t o l o c a l i z e d s i t e s and general ly must be sustained on a
regular basis. For example, a 100-m sect ion o f spawning grave l a t t h e o u t l e t o f Ruby Lake on the Sechelt Peninsula i n B r i t i s h Columbia
is 'cleaned annually with f i r e pumps and rakes (C. Wightman, BCFW,
personal communication). Gabions designed t o c o l l e c t spawning gravels, such as on a t r i bu ta ry of the Tr in i ty R iver i n northern
California, are cleaned at higher flows with f i r e pumps (K. Overton,
U.S. Forest Service [USFS], personal comunication).
Hydraul ic jets: A self-propelled amphibious veh ic le fo r c lean ing f ine sediment
from gravels was developed i n Alaska and Ca l i fo rn ia i n the 1960's
(Meehan 1971). The " R i f f l e S i f t e r " was abandoned due to operat ional
problems, but the concept of a hydraulic gravel cleaner has been revived i n the State o f Washington (Mih 1981). This machine uses
h igh ve loc i ty water j e t s t o d i s lodge sediments. The s i l t - laden water
was co l lected by a suct ion system and discharged on the streambank. Test resu l ts ind ica te that despite some promise, the gravel
cleaning machine has considerable l imi ta t ions (A l len " e t a l . 1981).
The machine i s n o t e f f e c t i v e i n non-uniform substrates, shallow
r i f f l e s , or i n systems with abundant organic mater ia l that has t o be
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removed beforehand to a l low the machine t o operate i n the stream. Gravel sampling i n Kennedy Creek, Washington, ind icated that the
l e v e l o f f ines re turned to pre-c leaning leve ls within one month, due
t o a recruitment o f f i nes from upstream areas. Test resu l t s were
more successful on Clear Creek which had ideal condi t ions o f f low con t ro l and uniform substrate size. Dick Al len (WSDF, personal
communication) ind icates that i n the future the gravel c leaning
machine will be used for c leaning spawning channels and side channels
that are being developed with contro l led- f low in le ts . He suggests that smal l llflashyll watersheds with unstable upslope areas are
to ta l l y unsu i ted for a gravel cleaning machine.
For the past 10 years, the IPSC has successful ly been using a
machine fo r c lean ing s ix spawning channels i n the Fraser River drainage. This machine i n j e c t s an a i r water mixture through pipes
inser ted 20 cm in to the subst rate (Andrew 1981). It i s only sui ted
f o r use i n spawning channels, as i t encounters d i f f i c u l t i e s i n
negot ia t ing t igh t corners and cannot operate if there are any stones
larger than 10 cm i n diameter, or i f a substant ia l amount of organic
mater ia l i s present. The cleaning operations are conducted when
f lows a re su f f i c ien t to car ry the s i l t - laden water out o f t he
spawning channel. In summary, a v a r i e t y o f experimentation with d i f ferent gravel
cleaning techniques i n the Pac i f i c Northwest appears t o have ar r i ved
a t a common consensus that gravel c leaning i s only useful i n spec i f i c
situations. Experience has shown that gravel cleaning operations are
most su i ted fo r s tab le systems such as lake-headed t r i b u t a r i e s or locat ions where some degree o f f low cont ro l has been achieved such as
i n spawning channels. I n s i tua t ions where the source o f sediment i s
not cont ro l led, the benef i ts o f gravel c leaning are qu ick ly negated. The gravel cleaning techniques discussed do not appear t o be
appropr iate for use i n t y p i c a l Queen Charlot te Is land streams tha t
have been damaged by mass wasting. Sediment inputs cont inue to occur
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a f te r t he l ands l i de event, and experience from e f f o r t s elsewhere
suggests tha t any benefits from mechanical gravel cleaning would be
short- l ived.
Upslope s t a b i l i t y programs:
I n stream systems with excessive accumulations o f sediments, the
most e f f e c t i v e r e h a b i l i t a t i o n measures will l i k e l y be those that
attempt t o s t a b i l i z e t h e upslope areas. It makes l i t t l e sense t o conduct extensive cleaning efforts i n the run-out and accumulation
zone, if excessive amounts of material are s t i l l entering the stream
from upslope areas.
The ef fect iveness of concentrat ing on watershed r e h a b i l i t a t i o n has been demonstrated on the South Fork Salmon River i n Idaho ( P l a t t s
and Megahan 1975). Road bu i ld ing and lands l i de ac t i v i t y i n t h i s
watershed increased the r iver bedload to the point that mainstream
spawning areas were choked with f ines. A moratorium on logging and a watershed r e h a b i l i t a t i o n program has resul ted i n a progressive
decl ine i n sediments i n spawning gravels, to the po in t tha t logg ing
a c t i v i t i e s have been allowed t o resume.
A second example o f e f f o r t s t o c o n t r o l sediments before they
enter the stream has been undertaken on Horse L i n t o Creek, a
t r i b u t a r y o f t h e T r i n i t y R i v e r i n northern Cal i fornia. A lands l ide
on t h i s system resul ted i n s i l t and sand accumulations two to th ree
t imes the pre-sl ide levels, and the spawning gravels have become imbedded with f i nes (G. Barnes, USFS, personal communication). In
1981, the U.S. Forest Service spent $200 000 to s tab i l i ze t he t oe o f
th is lands l ide , to s top the flow of f ines from contaminating the
substrate. These measures are costly, but should be e f fec t i ve and
long-last ing.
Probably the most extensive watershed r e h a b i l i t a t i o n program i n
North America i s present ly under way i n Redwood Creek, Cal i fornia.
Approximately $30 m i l l i o n i s being spent i n e f f o r t s t o s t a b i l i z e
sediment sources i n t h i s watershed. The program has successfully
- 13 -
reduced erosion from logging roads and landings, but has been unable to successfu l ly rehabi l i ta te debr is s l ides and avalanches and stored
channel sediments (Kelsey " e t a l . 1981).
Gravel placement and catchment
I n s i t u a t i o n s where spawning gravels are l imited, attempts have
been made t o add addi t ional gravel or t o s tab i l i ze ex i s t i ng g rave l
with in-stream structures. Most o f these attempts on West Coast
streams have been unsuccessful (Ha l l and Baker 19821, but continued
e f f o r t s and design modif icat ions are result ing i n greater success.
Gravel addition:
Addit ion of spawning gravel t o a natural, uncontrol led stream i s usually not successful (Canada Dep. Fish. and Oceans and B .C. Min.
Environ. 1980). Unless prevented from moving downstream, added gravel will often be deposited i n pools and around rocks and l o g
jams, to the det r iment o f salmonid rear ing habi tat . I n a t y p i c a l
small stream wi th a maximum width o f 10-14 m, slopes i n excess o f 0.3% produce veloci t ies that dur ing f reshets will readi ly move
spawning gravel (Canada Dep. Fish. and Oceans and B.C. Min. Environ.
1980). Successful pro jects invo lv ing gravel placement have general ly
taken place i n areas with stable f lows and dense spawning
populations. Examples o f use fu l add i t ions o f g rave l to spawning
areas include the Lardeau R iver a t the ou t le t o f T rou t Lake (Parkinson and Slaney 19751, and the ou t le ts o f Ruby and Chil l iwack
Lakes (C. Wightman, BCFW, personal comnunication) . Most streams af fected by mass wasting on the Queen Charlotte
Is lands are not gravel def ic ient unless they have e i ther been scoured
by a debr is tor rent or unless debris accumulations prevented adequate gravel recruitment downstream. Gravel s t a b i l i t y i s g e n e r a l l y a
greater concern, and techniques designed t o s t a b i l i z e e x i s t i n g
spawning gravels may be usefu l i n some streams where natura l
- 14 -
in-stream stabi l iz ing features, such as large organic debris, are
missing. Other techniques which have been used elsewhere are
gabions, log s i l l s , and rock weirs.
Gabions:
Gabions (rectangular wire-mesh baskets f i l l e d with rock) have been commonly used i n the Pac i f i c Northwest i n attempts t o h o l d
spawning gravel i n place. Hal l and Baker (1982) conducted an extensive review of gabion instal lat ions i n Oregon and Washington
streams, and concluded that the major i ty o f attempts t o i n s t a l l
gabions i n streams have been unsuccessful due t o s t r u c t u r a l
i n s t a b i l i t y or t h e f a i l u r e o f gabions t o r e t a i n adequate-sized
spawning gravels. There have been recent improvements i n gabion designs, which
suggest they can be a usefu l technique for co l lect ing and s t a b i l i z i n g
spawning gravels (Reeves and Roelofs 1982). One modif icaton that has
improved t h e s t a b i l i t y o f s t r u c t u r e s i s t h e use o f V-shaped
structures rather than the more conventional method i n which gabions
were placed perpendicular to the stream. A V-shaped gabion set a t 30' t o t h e bank will spread the water over double the distance o f a
conventional structure, and will reduce scour below the gabion (Anderson 1981).
The ends o f gabions are toed 1-1.5 m i n t o t h e banks and
r ip-rapped to prevent f lows from washing around the ends. Sections
are cabled together, and the en t i re s t ruc tu re i s cab led t o l a rge
trees or rocks near the banks. Anderson and Cameron (1980) estimate
tha t 90% o f the gabion structures instal led i n the Coos Bay D i s t r i c t
i n Oregon have remained reasonably stable. Construction costs f o r 38
structures completed i n 1981 ranged from $12-17 per l i nea l f oo t and
$500-2000 per structure (Anderson 1981).
Another recent improvement i n gabion design has been the use of
perforated pipes i n the base of gabions. The movement o f sands and
s i l t s through holes i n the pipes helps maintain cleaner gravels
- 15 -
behind the gabions ( K . Overton, USFS, personal communication). Perforated 10-cm diameter pipes placed i n the g rave l a t l - m i n te rva l s
are being used by the U.S. Forest Service i n northern Cal i fornia.
This "passive cleaning" modification may be par t icu lar ly appl icable
t o streams downstream of lands l ide areas which are subject t o t h e
deposi t ion of f ines f rom upstream si tes.
Log s i l l s :
Log s i l l s a r e an a l t e r n a t i v e t o gabions for use as s tab i l i ze rs
o f spawning gravels i n systems where l o g m a t e r i a l i s r e a d i l y
available. Although log s i l l s have been used i n a va r ie t y o f streams i n the Pac i f i c Northwest for the past 20 years, l i t t l e information on
t h e i r r e l a t i v e success as been documented.
Bender (1978) r e p o r t s t h a t f i v e l o g s i l l s p l a c e d i n Anv i l Creek,
Oregon, successful ly held spawning gravel that was subsequently used
by chinook salmon. Submerged logs have been used t o s t a b i l i z e spawning grave ls a t the ou t le t o f Ruby Lake (Canada Dep. Fish. and
Oceans and B.C. Min. Environ. 1980).
A r e h a b i l i t a t i o n program on Clear and Granite creeks i n Oregon
i s making extensive use of l o g s i l l s t o s t a b i l i z e g r a v e l s and develop
pool habi ta t (Andrews 1981). Over 100 log weirs, a t a cost o f approximately $900 each weir, are planned f o r these two creeks. Anderson (1981) repor ts that the const ruct ion costs o f 16 l o g s i l l s ranged from $400-900 per structure. The logs, keyed i n t o t h e bank up
t o 5 m, are l ined with a f i l te r fabr ic to p revent undercu t t ing . Log s i l l s t ruc tu res ins ta l led i n the Medford, Oregon, area have
remained i n t a c t a f t e r 8 years and despite a severe storm (B. Besey,
Bureau o f Land Management [BLM], personal communication). The WSDF
s t a r t e d u s i n g l o g s i l l s i n the l a te 1960's, changed t o gabion
construction, but are now re tu rn ing t o log s i l l s (D. Allen, WSDF,
personal communication). They are less expensive and are expected t o
l a s t as long as gabion structures.
- 16 -
Gabions o f fe r t he advantage of being l ight-weight, portable, and
possess more give than the log structures. As well , gabions and rock
weirs are not watertight. This promotes a good exchange o f f low
between the stream and the gravel spawning bed f o r a considerable
distance upstream o f the s t ruc tu re (Canada Dep. Fish. and Oceans and
B.C. Min. Environ. 1980). On the other hand, la rge wood mate r ia l f o r
l o g s i l l s i s abundant and readi ly ava i lab le on many streams i n the
Queen Charlotte Islands.
Both techniques have promise as methods of s t a b i l i z i n g and
co l l ec t i ng spawning gravels i n small Queen Charlotte Islands streams
tha t have h i s t o r i c a l l y had good f i s h runs but may be lack ing s tab le
spawning gravels.
Improved spawner access
A t h i r d approach t o spawning h a b i t a t r e h a b i l i t a t i o n i n the Queen Charlotte Islands i s the p rov is ion o f access f o r a d u l t spawners above
l o g jam ba r r i e rs . Ha l l and Baker (1982) repor t that despi te
extensive log jam removal programs throughout the Pacific Northwest,
few e f f o r t s have been made t o evaluate the ef fects o f l o g jam removal. They estimate that during the past 45 years, approximately
1000 debris accumulations have been removed on one r i v e r i n Oregon
alone.
Baker (1979) po ints out that a careful analysis should be made,
weighing the short-term impacts o f sediment and debris releases on
downstream rear ing and spawning habitat against the increased use by
anadromous f i s h above debr is jams. As an example, Brown (1975)
estimates that 300-500 m3 o f m a t e r i a l i s t y p i c a l l y s t o r e d behind a
3-5 m h igh l og jam, and Beschta (1979) indicated the removal of a l a r g e l o g jam i n coastal Oregon resul ted i n the release of 5000 m
of sediment. On the posit ive side, a l o g jam removed on Haslam Creek near Nanaimo resul ted i n improved adul t access t o an addi t ional 13 km
o f stream (Narver 1971).
3
- 17 - Many o f the debris accumulations associated with debr is torrents
on the Queen Charlotte Islands are formed near the upper extent of
anadromous f i sh hab i ta t , and only smal l gains to addi t ional spawning
areas may be made with the removal o f jams. A more important
consideration might be whether or not these jams are in ter rupt ing the f low o f g rave ls to downstream spawning areas. Consideration should
be g i ven t o t he pa r t i a l removal o f the jam around the side, to a l low
for cont inued movement o f bed materials without enormous releases of
sediment, and t o a l l o w f o r f i s h passage when i t i s determined tha t s ign i f i can t hab i ta t ex is ts above the barr ier . It should be
recognized however, t ha t t h i s cou ld l ead t o some bank erosion i f the
thalweg o f the stream re loca tes t o t h i s opening.
Log jam removal has been undertaken on the Queen Charlotte
Islands, often because the logs threaten bridges. For example,
debris accumulations from torrents have been removed on Sachs Creek
and South Bay Dump Creek ( K . Moore, WW, personal communication).
Oppor tun i t ies a lso ex is t to improve access t o upstream areas by
removing na tu ra l l og or rock barr iers. For example, extending
su i tab le access f o r coho, steelhead, and pink salmon i n t o upper Gate
Creek, Lye11 Island, might result i n far greater benef i ts to the
fishery resource compared to equiva lent stream res to ra t i on e f fo r t s i n Sandy Creek o r Richardson Creek, two streams on the same i s land which have been subject to extensive mass wasting events i n the past.
Methods of l o g jam removal depend on access and equipment
avai lable. A grapple yarder was used t o remove a l o g jam on Sachs
Creek a t a cost of approximately $2000. I n some s i tuat ions i t may be poss ib le to burn or salvage wood i n a jam and t o remove mater ia ls
from behind a jam (Canada Dep. Fish. and Oceans and B.C. Min.
Environ. 1980). Any res tora t ion work should be conducted as soon
a f te r t he event as poss ib le ( in the case of debris accumulations
associated with tor rents) so that the stream recovery will be
uninterrupted by subsequent stream r e h a b i l i t a t i o n a c t i v i t i e s , and so tha t merchantable wood may be recovered to he lp o f fset costs .
- 18 -
Side channel development
An a l t e r n a t i v e t o r e h a b i l i t a t i o n o f spawning gravels i n the main
channel o f a stream i s the development o f s ide channel spawning p a r t i c u l a r l y f o r p i n k , chum, and coho salmon. Under most s i tuat ions
s ide channels provide a more stable f low and temperature regime than
the main channel, and production i s usua l l y l im i ted by inadequate
water during certain periods. Efforts to concentrate seepages and
subsurface flows to p rov ide adequate spawning and incubation f lows
can be complemented with a v a r i e t y o f channel improvement e f fo r ts ,
such as establ ishing gradient controls with gabions, improving
spawning gravels, and const ruct ing pools for ho ld ing f ish (Canada
Dep. Fish. and Oceans and B.C. Min. Environ. 1980). Chum salmon spawning areas have been developed i n a number o f
groundwater-fed side channels i n southwestern B r i t i s h Columbia (L i s te r " e t a l . 1980). Egg-to-fry survival i n these areas was
approximately double the average recorded a t n a t u r a l spawning locat ions i n the province. The development o f a side channel
spawning area f o r chum salmon has been i n i t i a t e d on the Satsop River
i n Washington (D. Allen, WSDF, personal communication). This channel
has been dyked, water l eve l s a re con t ro l l ed a t a c u l v e r t i n l e t , and a
ser ies o f gabions have been i n s t a l l e d t o h o l d g r a v e l i n place.
The development o f s tab le s ide channel spawning areas i n some
streams on the Queen Charlot te Is lands may serve as a compensatory
measure i n l i e u o f spawning area r e h a b i l i t a t i o n o f those small streams d i rec t l y a f fec ted by mass wasting, but which themselves are
poor candidates f o r g r a v e l r e h a b i l i t a t i o n due to unstable upslope
areas. Even side channels could be af fected by h igh l eve l s o f
suspended sediment resu l t i ng from upslope fa i lu res .
Incubation boxes
Stream-side incubat ion boxes can be used i n conjunction with r e h a b i l i t a t i o n p r o j e c t s t o ensure that stocks are maintained and tha t
stream production i s rapidly brought to i t s p o t e n t i a l i n areas where
- 19 -
spawning gravel restorat ion has occurred. I n Washington State,
incubation boxes are also used t o p a r t i a l l y m i t i g a t e salmonid
production losses due t o land-use act iv i t ies (Bauersfe ld " e t a l . 1981).
On the Queen Charlot te Is lands incubat ion boxes have been used
with some success i n Sachs and Hans creeks on Moresby Island, and i n
Thorsen Creek, Sewel l In le t . As experience i s gained and stable water suppl ies ident i f ied, th is program should improve and incubation
boxes may o f fe r a l im i ted subs t i t u te spawning environment t o a t l e a s t
maintain stocks i n streams where spawning gravels have deter iorated
as a r e s u l t o f mass wasting. The c o s t o f i n s t a l l a t i o n and maintenance o f the two boxes on Hans and Sachs creeks was $20 000
d u r i n g t h e f i r s t year and should be less dur ing subsequent years
(B. Pollard, MacMillan Bloedel Ltd., personal communication).
Before outplanting fry from an incubation box i n t o a debris torrented stream, an assessment o f the to ta l ava i lab le hab i ta t i n
tha t stream should be made.
Rearing habitat
There are a number o f techniques suitable for juvenile coho and
steelhead rear ing habi tat rehabi l i tat ion. These include the
placement of in-stream structures to improve hab i ta t d i ve rs i t y and increase cover for juveni le f ish, side channel development, and the enhancement o f backwaters and groundwater-fed pond areas. Techniques
such as f low augmentation, semi-natural rearing channels, and stream
enrichment are not discussed i n this report s ince they are not
considered real ist ic opt ions for use i n the types of streams that are
damaged by mass wasting i n the Queen Charlotte Islands.
In-stream structures
In-stream structures t o enhance trout populat ions have been used extensively i n the mid-eastern United States. The most deta i led and
comprehensive evaluat ion o f t rout habi ta t development has been
carr ied out i n Lawrence Creek, Wisconsin (Hunt 1976). The use o f
- 20 -
in-stream structures t o increase pools and overhead cover resul ted i n substantial increases i n the older age classes of brook t rout . White
and Brynildson (1967) have reviewed many of the techniques suitable
f o r use i n small, meandering streams with moderate f low regimes. The
app l ica t ion o f these techniques t o West Coast streams i s probably l i m i t e d t o t h e more stable lake-out let systems.
A number of in-stream structures for rear ing habi tat improvement
have shown promise fo r Pac i f i c Northwest streams. Boulder clusters, l o g placements, gabions, and the development of pools by blast ing i n bedrock streams are presently used t o improve rear ing habi tat .
Boulder placement: The use of boulders to increase rear ing habi ta t for juveni le
coho and steelhead i s probably the most e f fec t i ve technique i n most
B r i t i s h Columbia streams (Canada Dep. Fish. and Oceans and B.C. Min.
Environ. 1980). A deta i led s tudy o f d i f ferent conf igurat ions o f
boulder placement was conducted i n the Keogh River on northern
Vancouver Is land (Ward and Slaney 1979). Boulders arranged i n
c lus te rs o f up t o seven were an e f fec t i ve means of improving steelhead parr and coho f i nge r l i ng rea r ing hab i ta t i n a sect ion o f
r i v e r t h a t had previously been logged and had much o f i t s in-stream
cover removed by a stream clearance program. Boulders o f approximately 60-100 cm i n diameter proved t o be the best for both
s t a b i l i t y and scour effect. Boulder V-notched weirs, and boulder def lectors with l o g cover were found t o be less s tab le and had lower
d e n s i t i e s o f f i s h use than the clusters. Attaching log cover to
boulder c lusters resul ted i n s l i gh t l y h ighe r f i sh dens i t i es (Ward a;d
Slaney 1979). The use of a hel icopter to p lace boulders compared favourably with the costs of using heavy equipment.
Boulder placements i n Red Cap Creek, California, increased the
steelhead parr populat ion three-fold over control sections (Brock
1982). Some boulders were bur ied i n deposited bedload during a
- 21 -
winter freshet. More severe problems were encountered on the Salmon River, Vancouver I s land , where boulder placements were ine f fec t ive due t o t o o much bedload being deposited around the boulders. A t l eas t four o ther s t reams in southwes tern Br i t i sh Columbia have recent ly had boulders added t o improve t r o u t and coho rear ing habi ta t (C. Wightman, BCFW personal communication). As well, a small program of boulder placements is presently being undertaken on Brent Creek i n the Gueen Charlot te Is lands (6. Pollard, MacMillan Bloedel Ltd. , personal communication).
Boulder placement i n clusters could be a useful technique f o r improving rearing habitat on some Queen Charlotte Island streams, pa r t i cu la r ly i n sma l l s t ee lhead systems that lack overwinter cover fo r pa r r . As wi th most s t ream rehabi l i ta t ion methods, t h i s technique i s most s u i t e d f o r s t a b l e , lake-headed systems, and boulder placement elsewhere will result i n a high p o s s i b i l i t y of structure f a i l u r e .
Log sills and gabions: Log sills and gabions were discussed previous ly as a means of
s t a b i l i z i n g spawning gravels . The plunge pool formed below the gabion or log si l l may also provide juveni le rear ing habi ta t (Anderson and Cameron 1980; Andrews 1981). In many of our small coastal streams, t h e a v a i l a b i l i t y of pool habitat during lowest flows may limit t h e s t ream's rear ing capac i ty , par t icu lar ly for o lder age c l a s s e s of juveni le s teelhead and coho. The addi t ion of pool hab i t a t could increase the rearing capacity of these streams.
Gabions i n s t a l l e d i n the Keogh River d i d not increase the abundance of s tee lhead par r (Ward and Slaney 1979). They provided l i t t l e hab i t a t d i v e r s i t y and were s t r u c t u r a l l y unsound compared t o boulder structures. The gabions d i d provide some winter cover for s teelhead, and i t was noted that they may be useful i n some small coho nursery s t reams, par t icu lar ly i f combined w i t h boulder placements.
- 22 -
Blasting pools:
The importance of poo l hab i ta t to juven i le rear ing has
s t imu la ted e f fo r ts to c rea te new pools i n streams lack ing pool
habi tat . For example, a program o f b las t i ng and excavating pools i n the bedrock substrate of Vincent Creek, Oregon (80% r i f f l e and 2lX
poo l hab i ta t a t low f lows) resulted i n a s igni f icant increase i n the
abundance of juveni le coho salmon (Anderson and Miyajima 1975). Several other programs involv ing pool b last ing i n Oregon streams have
met with mixed success ( H a l l and Baker 1982). Developing pool
habi ta t i n bedrock streams i s also a continuing stream improvement
program i n Alaska (Sweet 1975). Reported costs for pool b last ing range from $200-400 per pool (Sweet 1975; Anderson 1981).
B last ing bedrock pools may have potent ia l for improv ing coho
rear ing habi ta t on some Queen Charlot te Is land streams tha t possess bedrock substrate and lack pool habi ta t . However, new pools would have t o be designed t o ensure they did not completely fill with bedload, and cont inued to of fer sui table habi tat dur ing f reshets.
Other in-stream techniques:
A number of other in-stream techniques aimed a t p rov id ing cover
f o r j u v e n i l e salmonids i n streams def ic ien t i n na tura l cover may have
merit . For example, t rees can be attached to t he streambank and t o
instream boulders, or root wads can be anchored a t key l oca t i ons t o
provide cover (Canada Dep. Fish. and Oceans and B .C. Min. Environ.
1980). Root wad structures have been i n s t a l l e d i n Colquitz Creek
near V ic to r ia to p rov ide cover fo r coho and c u t t h r o a t t r o u t i n t h i s
small urban stream. These techniques are essentially untested i n the Paci f ic
Northwest, but have the advantage of using natural mater ia ls readi ly
avai lable. However, the i r potent ia l for creat ing debr is
accumulations i n small streams and the i r re la t i ve l y sho r t l i f e -span
may limit their appl icat ion.
- 23 -
Side channel and Dond develoDment:
Side channel areas t y p i c a l l y o f f e r more s tab le rear ing
conditions than main channel s i tes. Ef for ts to concentrate seepages and provide stable f lows i n side channels can be complemented with a var ie ty of in-stream structure developments t o improve rear ing
habi ta t (Canada Oep. Fish. and Oceans and B.C. Min. Environ. 1980).
This approach could he lp to compensate for habi tat degradat ion i n main channel s i tes, where r e h a b i l i t a t i o n e f f o r t s may be short-term
due t o extreme flows and high bedload movement. In te rmi t ten t f lood channels and groundwater-fed pond areas
adjacent t o streams provide important overwinter ing habi tat for juven i le coho (Bustard and Narver 1975; Peterson 1980). Improvement
o f these areas by developing access and concentrating f lows may be a useful technique to increase a stream's c a p a b i l i t y t o produce coho smolts. It might also prove less labour-intensive than using
in-stream structures.
CONCLUSION
A var iety of avai lable techniques of fer some po ten t ia l means of
r e h a b i l i t a t i n g Queen Charlotte Islands streams af fected by mass wasting. I n th is rev iew i t was assumed tha t po ten t i a l impacts t o spawning f i s h would include a deter iorat ion o f spawning gravel qual i ty and s tab l i t y , and a loss o f
upstream access t o former spawning areas.
After considerable experimentation with gravel cleaning techniques i n the
Pac i f i c Northwest, there i s a common consensus that gravel c leaning i s
unsui table for use i n the small, high-energy streams typ ica l l y sub jec ted to landsl ides i n the Queen Charlotte Islands. A program o f watershed
s t a b i l i z a t i o n t o reduce sediment i npu ts t o stream systems, i n add i t i on t o
temporary measures such as incubation box f a c i l i t i e s t o ensure the maintenance
o f spawning stock, may be the on ly e f fect ive means of deal ing wi th
deter iorated gravel qual i ty i n spawning areas. Gabion and l o g s i l l s t r u c t u r e s
o f fe r a means of improving spawning g r a v e l s t a b i l i t y i n areas where natura l
- 24 -
s tab i l i z ing fea tures have been los t . Recent improvements i n structure design, inc lud ing V-shapes and perforated pipes for passive cleaning of f ines, should
improve the success r a t e of these in-stream structures. As well, the
development of stable side channel areas f o r spawners holds promise as a means
o f spawning s tock rehab i l i t a t i on i n s i tua t ions where su i tab le s i t es can be
ident i f ied .
Mass wasting events may also adversely af fect the rear ing habi tat of
juveni le salmonids as a r e s u l t of the red is t r ibu t ion o f la rge o rgan ic debr is and o f changes i n channel character is t ics that resul t i n less pool habi ta t and
more subsurface flows. A var ie ty of techniques have promise as means o f
r e h a b i l i t a t i n g r e a r i n g areas, ranging from the development o f in-stream
structures such as boulder placements, l o g s i l l s , and gabions t o improve
hab i ta t d i ve rs i t y and the amount of pool area; to off-channel developments such as side channel and pond rear ing areas. Each o f these techniques centres
on d i f f e r e n t l i f e h i s t o r y stages of salmonids, and requires a thorough
understanding of the factors l imi t ing product ion before they can be
e f fec t i ve l y undertaken. Techniques that focus on areas adjacent to, rather than i n the main channel i t s e l f , will probably be most durable and ef fect ive.
I n conclusion i t i s important to point out that i t i s more economical t o
prevent i n i t i a l hab i ta t deg rada t ion t han t o repa i r it, and some damage i s not
reversible (Narver 1973; H a l l and Baker 1982). Resource managers must be cautioned that, at the planning and execution stage of forestry operations,
stream r e h a b i l i t a t i o n i s n o t a reasonable a l te rna t i ve t o sound habi ta t
protect ion measures.
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LlTERATURE CITED
Allen, R.L., J.E. Seeb, and D.D. King. 1981. A prel iminary assessment o f f ie ld opera t ions with a salmon-spawning gravel cleaning machine. In: Salmon-spawning gravel: a renewable resource i n the Paci f ic Nor thwzt? Rep. No. 39. Washington State Water Research Center, Pullman, Wash.
Anderson, J.W. 1981. Anadromous f i sh p ro jec ts . 1981. U.S. Dep. Agric. Bureau o f Land Manage. In: Proc. Propagation, Enhancement, and Rehabi l i ta t ion of Anadromous SalEnid Populat ions and Habitat i n the Pac i f i c Northwest Symp., Oct. 15-17, 1981. Humboldt State Univ., Arcata, Cal i f .
Anderson, J. W. and J. J. Cameron. 1980. The use o f gabions t o improve aquatic habi tat . U.S. Dep. Agric. Bureau Land Manage., Ore. Tech. Note No. 342.
Anderson, J.W. and L. Miyajima. 1975. Analysis of the Vincent Creek f i s h rear ing pool pro ject . Tech. Note No. 274. U.S. Bureau o f Land Manage., Coos Bay, Ore.
Andrew, F.J. 1981. Gravel cleaning t o increase salmon production i n r i v e r s and spawning channels. In: Salmon-spawning gravel: a renewable resource i n the Paci f ic Nor thwestF Rep. No. 39. Washington State Water Research Center, Pullman, Wash.
Andrews, J. 1981. Clear Creek and Granite Creek anadromous f i s h rehab i l i ta t ion . Tech. Rep. U.S. Dep. Agric. For. Serv., Pendleton, Ore.
Baker, C.O. 1979. The impacts o f l o g jam removal on f ish populat ions and stream habitat i n western Oregon. M.Sc. thesis. Oregon State Univ., Corval l is , Wash.
Bauersfeld, K.L., L.R. Cowan, and T.J. Burns. 1981. Salmon Natural Production Enhancement Program, 1979-80 season. Progress Rep. No. 136. State o f Wash. Dep. of Fish.
Bender, R. 1978. Log s i l l s . In: Proc. o f f i s h h a b i t a t improvement workshop, Sept. 26-27, 1978. Oregonxep. o f F i sh and W i l d l i f e Br., Portland, Ore.
Beschta, R.L. 1979. Debris removal and i t s e f f e c t s on sedimentation i n an Oregon Coast Range stream. Northwest Sci. 53:71-77.
Bjornn, T.C., M.A. Brusven, M.P. Molnau, J.H. Mi l l igan, R.A. Klamt, E. Chacho, and C. Schaye. 1977. Transpor t o f grani t ic sediments i n streams and i t s e f fec ts on insects and f i sh . For. W i l d l i f e and Range Exp. Stn., Completion Rep., Water Resour. Res. Inst. Proj. 8-036. IDA. Univ. Idaho, Moscow, Idaho.
B.C. F ish and W i l d l i f e Branch. 1970-80. Steelhead harvest analysis. B.C. F i sh and W i l d l i f e Br., Victor ia, B.C.
- 26 -
Brock, 8. 1982. Enhancement of rear ing habi ta t for juveni le s tee lhead t rout by boulder placement i n a t r i b u t a r y t o t h e Klamath River. M.Sc. thesis. Humboldt State Univ., Arcata, Ca l i f .
Brown, G.W. 1975. Managing water quality. In: Logging debris i n stream workshop. Oregon State Univ. , Corval l is , Ore.
Bryant, M.D. 1980. Evolut ion of large, organic debr is af ter t imber harvest: Maybeso Creek, 1949 t o 1978. U.S. Dep. Agric. For. Serv., Gen. Tech. Rep. PNW-101.
Bustard, D.R. and D.W. Narver. 1975. Aspects of the winter ecology o f juven i le coho salmon (Oncorhynchus kisutch) and steelhead t rout (Salmo gairdner i ) . J. F ish Res. Board Can. 32:667-680.
Canada Department of Fisher ies and Oceans and B.C. Min is t ry o f Environment. 1980. Stream enhancement guide. Salmonid Enhancement Program. Vancouver, B.C.
Cederholm, J. and E.O. Salo. 1979. The ef fects o f logging road lands l ide s i l t a t i o n on the salmon and t r o u t spawning gravels o f Stequaleho Creek and the Clearwater River basin, Jefferson County, Washington, 1972-1978. F i n a l Report - Part 111. Univ. Washington, Fish. Res. Inst., FRI-UW-7915.
Department o f Fisher ies and Oceans. 1978 and 1979. Prel iminary catalogues of salmon streams and spawning escapements o f s t a t i s t i c a l areas 1, 2E and 2W (3 separate reports). Vancouver, B.C.
Hall , J.D. and C.O. Baker. 1975. B io log ica l impacts of organic debris i n Pac i f i c Northwest streams. In: Logging debris i n streams workshop. Oregon State Univ., C o r v a l l i g Ore.
. 1982. Rehabi l i ta t ing ana enhancing stream habi ta t : 1 Review and evaluation. ReDort 12, In: Influence o f fo res t and rangeland management on anadromous f i s h h a b i t a t i n Western North America. W.R. Meehan (ed i tor ) . U.S. Dep. Agric. For. Serv., Gen. Tech. Rep.
"
Heiser, D.W. 1972. Spawning ground improvement - gravel loosening 1971-72. Progress Rep., Wash. Dep. Fish., Olympia, Wash.
Hunt, R.L. 1976. A long-term evaluation of t rou t hab i ta t development and i t s re la t ion to improv ing management-related research. Trans. Amer. Fish. SoC. 105(3) :361-364.
Kelsey, H.M., M. Madej, J. ? i t l i c k , P. Stroud, and M. Coghlan. 1981. Major sediment sources and l im i ts to the e f fec t i veness o f e ros ion con t ro l techniques i n the highly erosive watersheds of nor th coasta l Cal i forn ia . - In: Symp. of Erosion and Sediment Transport i n Pac i f i c R i m Steeplands, Christchurch, N.Z., IAHS Publ. No. 132.
- 27 -
L is le , T.E. 1981. The recovery o f stream channels i n nor thern Cal i forn ia from recent large f loods. In: Proc. o f a Symp. o f Habitat Disturbance and Recovery, sponsored byxa l i fo rn ia T rou t , Inc . and the American Fisher ies Society, January 29, 1981, San Lu is Obispo, Cal i f .
L is te r , D.B., D.E. Marshall, and D.G. Hickey. 1980. Chum salmon surv iva l and product ion at seven improved groundwater-fed spawning areas. Can. MS Rep. Fish. Aquat. Sci. 1595.
Mason, J.C. 1976. Response of underyear l ing coho salmon t o supplemental feeding i n a na tura l stream. J. Wildl. Manage. 40:775-788.
Meehan, W.R. 1971. Ef fects o f gravel cleaning on bottom organisms i n three southeast Alaska streams. Prog. Fish-Cult. 33(2) :107-111.
Mih, W.C. 1981. Research and development o f a salmon spawning gravel cleaner (Gravel Gertie). In: Salmon-spawning gravel: a renewable resource i n the Pac i f i c Northwest? Rep. No. 39. Washington State Water Research Center, Pullman, Wash.
-
Narver, D.W. 1971. Ef fects o f logging debr is on f i s h production. In: Proc. o f a Symposium on Forest Land Uses and Stream Environment, Oregon State Univ. Corval l is , Ore.
. 1973. Are hatcheries and spawning channels a l t e rna t i ves t o stream protection? Fish. Res. Board Can. Circ. 93. Pac. B io l . Stn., luanaimo, B.C.
Nichelson, T.E. and R.E. Hafele. 1978. Streamflow requirements of salmonids. Progress Rep. Oregon Dep. F ish and Wildl. AFS-62. Contract 14-16-0001-77-538, Portland, Ore.
Parkinson, E.A. and P.A. Slaney. 1975. A review of enhancement techniques app l icab le to anadromous gamefishes. B.C. F ish and Wildl. Br., Fish Manage. Rep. No. 66.
Peterson, N.P. 1980. The r o l e o f s p r i n g ponds i n the winter ecology and natural product ion of coho salmon (Oncorhynchus kisutch) on the Olynpic Peninsula, Washington. M.Sc. thesis. Univ. o f Wash., Seattle, Wash.
Ph i l l i ps , R.W. 1971. E f fec ts o f sediment on the gravel environment and f i s h production. In: Proc. o f a Symp. on Forest Land Uses and Stream Environment, Oregon State Univ., Corval l is , Ore.
Pla t ts , W.S. and W.F. Megahan. 1975. Time trends i n channel sediment s ize composition i n salmon and steelhead spawning areas: South Fork Salmon River, Idaho. Trans. North Am. Wildl. Nat. Resour. Conf. 40:229-239.
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Reeves, G.H. and T.D. Roelofs. 1982. Rehabi l i ta t ing and enhancing stream habi tat : 2 Field appl icat ion. Report 13, In: In f luence o f forest and rangeland management on anadromous f i s h h a b x a t i n Western North America. W.R. Meehan (ed i tor ) . U.S. Dep. Agric. For. Serv., Gen. Tech. Rep.
Scrivener, J.C. and M.J. Brownlee. 1981. A prel iminary analysis of Carnation Creek grave l qua l i t y data, 1973-1980. In: Salmon-spawning gravel: a renewable resource i n the Pac i f i c Northwest? Rep. No. 39. Washington State Water Research Center, Pullman, Wash.
Slaney, P.A., T.G. Halsey, and A.F. Tautz. 1977. Ef fec ts o f fo res t harves t ing pract ices on spawning hab i ta t o f stream salmonids i n the Centennial Creek Watershed, B r i t i s h Columbia. B.C. F ish and Wildl. Br., Fish. Manage. Rep. No. 73.
Swanson, F.J. and G.W. Lienkaemper. 1975. The h i s to ry and phys ica l e f fects o f large organic debr is i n western Oregon Streams. In: Logging debris i n streams workshop. Oregon State Univ., Corva l l i s ,x re ,
Swanson, F.J., G.W. Lienkaemper, and J.R. Sedell. 1976. History, physical e f fects , and management impl icat ions o f large organic debris i n western Oregon streams. U.S. Dep. Agric. For. Serv., Gen. Tech. Rep. PNW-56.
Swanston, D.N. 1980. Impacts o f n a t u r a l events. In: Inf luence of forest and rangeland management on anadromous f i s h h a b i t a F i n Western North America. W.R. Meehan (edi tor ) . U.S. Dep. Agric. For. Serv., Gen. Tech. Rep. PNW-104.
Sweet, M. 1975. Fish habi ta t improvement in format ion for the Alaska Region. U.S. Dep. Agric. For. Serv., Region 10, Aneau, Alaska.
Ward, B.R. and P.A. Slaney. 1979. Evaluation of in-stream enhancement structures for the product ion of juveni le steelhead t rout and coho salmon i n the Keogh River: progress 1977 and 1978. B.C. Min. Environ. Fish. Tech. Circ. No. 45.
White, R.J. and O.M. Brynildson. 1967. Guidelines for management o f t r o u t stream habi ta t i n Wisconsin. Wisc. Dep. o f Nat. Resources, Tech. Bu l l . No. 39.
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APPENDIX
PROPOSED 1982 PILOT REHABILITATION STUDIES
The fo l l ow ing ou t l i ne f o r po ten t i a l stream rehab i l i t a t i on s tud ies which can be implemented by the FISH/FORESTRY INTERACTION PROGRAM i n 1982 has been
prepared without the benefit of resu l t s from ongoing impact studies.
Accordingly, this stage of the program should be kept small and f l e x i b l e un t i l such resu l t s can be incorporated i n t o t h e design. Pre l iminary rehabi l i ta t ion
s t u d i e s i n i t i a t e d i n 1982 could serve as a t e s t program for techniques which
may be applied on a larger sca le a t a l a t e r date. Based on information derived elsewhere, it i s assumed tha t downstream of
mass wasting, spawning gravels i n streams less than 2 percent gradient are accumulating coarser part icles, not readi ly f lushed out during freshets. It
i s a lso assumed that gravels i n spawning areas have become less s tab le as a
r e s u l t of red i s t r i bu t i on of large organic matter and the accumulation o f
excessive bedload material. These factors probably resul t i n poorer survival
of salmonids, pa r t i cu la r l y pink and chum salmon. Fo r t h i s reason, i t i s
recommended tha t a major emphasis o f stream rehabi l i tat ion should focus on the
prov is ion of a stable spawning environment with clean gravels for p ink and
chum salmon egg and a lev in development. The most f ru i t fu l approach f o r long-term inprovement o f stream condit ions
is t o s t a b i l i z e upslope s i t e s which are cont r ibut ing t o in-stream problems. It i s recommended tha t any in-stream rehabi l i tat ion program should work i n close conjunction with upslope watershed s t a b i l i z a t i o n e f f o r t s .
Sachs Creek, with i t s h i s to ry o f l ogg ing - re la ted mass wasting problems, i s
a good candidate watershed t o conduct p i l o t s tud ies o f several stream r e h a b i l i t a t i o n techniques. It has h i s t o r i c a l l y had good escapements o f p ink
salmon (annual average 2,500 f i sh) . As well, Sachs Creek has a run of chum and coho salmon, steelhead and cu t th roa t t rou t (Salmo c l a r k i ) and Dol ly Varden
char (Salvelinus malma). There i s good access to the lower 2 km o f Sachs
Creek, the main spawning and rearing area for anadromous fish. Furthermore,
MacMillan Bloedel Ltd. i s in terested i n a j o i n t r e h a b i l i t a t i o n program i n t h i s
watershed. An ex is t ing incubat ion box program for p ink and coho salmon on
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t h i s stream should assist continued spawner recruitment despite apparent de t e r io ra t ed cond i t ions i n t he spawning gravels following a major debris t o r r e n t i n upper Sachs Creek i n October 1974.
A p i l o t rehabi l i ta t ion s tudy on Sachs Creek could involve the following projects:
1) A series of gabions and log sills could be e s t a b l i s h e d i n the lower 2 km of Sachs Creek t o s t a b i l i z e spawning areas . Long riffles could be separated t o c r e a t e p o o l - r i f f l e complexes which would improve the s t a b i l i t y of spawning grave ls and d ive r s i fy rear ing habi ta t . Perforated pipes i n s t a l l e d i n t o t h e gab ion s t ruc tu res t o improve g rave l qua l i t y by 'Ipassivell movement of f i n e s is the most promising technique t o improve spawning grave l qua l i ty . A series of 10 log sills and 10 gabion structures i n pa i r s t o compare ef fec t iveness and du rab i l i t y o f t h e two techniques would cost approximately $40,000
based on experience elsewhere. 2) A s tudy of r e a r i n g h a b i t a t development aimed primarily a t improving
juven i l e coho overwinter ing habi ta t in side channels and ponds could be undertaken on Sachs Creek. A p o t e n t i a l side channel development s i te is loca ted 1500 m upstream on Sachs Creek. Possible opt ions f o r t h i s s i te include the development of channels and pools on the f l a t s between t h e main and side channels, a control structure a t the top end of t h e channel to modify winter freshets and ensure adequate. flows during low summer periods, and the placement of log structures for diversity and cover.
A small pond located at approximately 1900 m on Sachs Creek may be suited f o r coho rear ing. The development of access i n to t h i s pond from Sachs Creek or s tocking i t using coho f ry produced i n the incubat ion box could be tested t o enhance the coho r ea r ing po ten t i a l of Sachs Creek.
Cost es t imates for these developments would be dependent on further f ield evaluations including preliminary enqineering work assess ing the s u i t a b i l i t y of these sites f o r d e t a i l e d work. Additional cost allowances for any in-s t ream rehabi l i ta t ion p ro jec ts
- 31 - should include the cost of maintenance of s t ructures on an annual
basis (est. l a ) and contract administration costs. As well,
programs designed to evaluate the ef fect iveness of in-stream works
would be required. For example, the rear ing projects would require
deta i led assessments o f j uven i l e salmonid production pre- and
post-development, including the possible use of t rapping dev ices to
determine smolt output from the side channel and pond area.
Other stream rehab i l i t a t i on p ro jec ts which might be undertaken
include the fo l lowing : P a r t i a l l o g jam removal programs on debris torrented creeks which no longer have adequate gravel recruitment. For example,
the removal o f p a r t o f t h e log jam on Showmar Creek ( t r i bu ta ry of the Deena River) and on a t r i bu ta ry o f Mosquito Lake may
benef i t downstream areas which are deficient of spawning gravels.
Pond and side channel developments i n other systems fo r bo th rear ing and spawning habi ta t ho ld promise. This program would
depend on f i e l d crews ident i f y ing su i tab le s i tes dur ing the
course o f stream surveys. The Deena River may of fer a number o f
oppor tun i t ies fo r such developments.
A program to re -es tab l i sh s t ream cont ro l s t ruc tu res to co l lec t and stabilize gravels i n MacMillan Creek has a h igh p robab i l i t y o f f a i l u r e due t o upslope i n s t a b i l i t y , a high gradient channel
(3.5% slope i n lower reach) and h i s t o r i c a l l y poor recruitments
o f f ish. It does have the benef i t o f easy access and large
woody mater ia l readi ly ava i lab le. It i s improbable that the benef i ts to the f isher ies resource from rehab i l i t a t i on works i n
a stream with the character ist ics of MacMil lan Creek could ever
be cost-effect ive.