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<br />PLANT 6 REACH 6
<br />/"/.
<br />~.
<br />PLAN!:'(:? I REACH 5
<br />/ ,._.~
<br />I ../ R CH 4
<br />/.....:' PLAN j
<br />/ ;...-'.. 1
<br />/" \
<br />.,....,...:.:..;PLANl{ 3 "
<br />/-/ 'b" \.
<br />/...,., ").-0.....'"'
<br />1:'/ REACH 2 :..>'~ '..... '/
<br />'.' c....
<br />~ ('/~LANT2 -9~~....\\
<br />/. , +}
<br />1 if :/
<br />" N / +'1\ //
<br />// / ,.'!S /.1
<br />'.<6: \. ....-", \"J:. .' ..'
<br />'~, .. - ./." t I'
<br />,'/of .......__ ~d i"'" .' .
<br />) '~C?!$.BISHOp'~C.~EK I~ ..,/,1~. .......
<br />') -,'-..-" (?; ;; / I /'
<br />',,-, 'v, ,/ .
<br />/~ i:r i j,-
<br />I /?U i~ ,...
<br />\. )-iAKE SABRIN~\.~ ';
<br />...... 19.. .(<'\
<br />\ if; )"f- /
<br />,\~ ,; (
<br />)'~ O'SOUTH LAKE LEGE!'il)
<br />\ i'l... I. __ Wal......h..d boundary
<br />d. 'r' \. (aboH' PO\.H'rplant 6
<br />(" ;' .... ~ ) - - Crf'-..k
<br />\ <J.,.; 'I / ..... Din'l'Sion
<br />-_/ --, 1,. 1
<br />. I'o......rplanl
<br />,~) b_>, 'I ~ 3
<br />___...... 1 'r I
<br />
<br />.'Jil<1077
<br />
<br />rns such as Bishop
<br />Qung age of many
<br />indicates that cli-
<br />,d Cotton .....ood es.
<br />resence of cotton-
<br />density in man v
<br />as an i~dicator of
<br />nstream flows for
<br />r maintenance aff'
<br />Episodic recruit-
<br />Bishop Creek has
<br />'eriodic pr~nce
<br />g appropriate pe.
<br />er becomes avail-
<br />:apacity of the hr-
<br />:n is exceeded in
<br />'~quent years of
<br />in stress and mor-
<br />~velopment of in-
<br />dels for riparian
<br />
<br />
<br />!leased into the
<br />, lowermost pow-
<br />'mal "ears, these
<br />99% greater than
<br />'eaches between
<br />vears the.... have
<br />~nd Nachlinger
<br />diverted reaches
<br />'\m1 in dry years
<br />years. flows in
<br />high, with daily
<br />.year flood limit
<br />>40 m'/s).
<br />located in four
<br />~ek, as described
<br />
<br />'M'
<br />
<br />FIGURE 1. Lo~~tion of study re~~hH ~t Bishop Creek, Inyo County, C~lilorn;,1.
<br />
<br />'M
<br />
<br />Grev. & Balf.), quaking aspen (Populus (rem-
<br />uloldes Michx.), water birch (Betula oCCldell-
<br />tailS Hook), and ",,'iIIow (SaTix spp.). Black
<br />cottonwood is present discontinuously
<br />within the reach.
<br />Reach 4 is between power plants 4 and
<br />5 al ca. 1.475 m. It is an effluent reach in
<br />an alluvial outwash plain, ",,'ith a stream
<br />gradient of ca. 4%. Annual flows have av-
<br />eraged ca. 13.6 hm), of which 100% has
<br />been in the growing season. Riparian veg-
<br />etation is sparse and discontinuous, with
<br />only scattered patches of trees. Two s~cit'S
<br />of cottonwood, black cottonwood and Fre-
<br />mont cottonwood (P. f,emont,i Wats.). grow
<br />in the reach.
<br />Reach 5 is between power plants 5 and
<br />6 at ca. 1.390 m in an alluvial outy,'ash plain.
<br />The upper portion of the reach may be
<br />effluent, but in the lower portion surface
<br />flow is augmented by a series of springs
<br />(Hess and Smith 1987; Space et al. 1989).
<br />
<br />wer plants 2 and
<br />t020 m. It is an
<br />Iped valley with
<br />stream gradient
<br />Associates 1990).
<br />I 196Q to 1988 for
<br />been ca. 9 hm1,
<br />the growing sea-
<br />Ire 2). (Prt'-1969
<br />:or this reach and
<br />Annual average
<br />~ woody riparian
<br />'nst', consisting
<br />xi (Populu'f. ,,/Clro-
<br />ne (Pmu5 JejJ,.'.1I1
<br />
<br />January I q91
<br />
<br />I J. C. Stromberg and D. T. Patten
<br />
<br />Stream gradient averages ca. 3%. Annual
<br />flows have averaged ca. 16.4 hm', with
<br />91% occurring in the growing season. Ri-
<br />parian vegetation is scanty, with only scat.
<br />tered pockets of Fremont cottonwood and
<br />other riparian plant species.
<br />Reach 6 is below the discharge dam at
<br />power plant 6, in an alluvial outwash plain
<br />at 1,380 m. Surface flow in this flo......sup-
<br />plemented reach has averaged ca. 103.8
<br />hm 1, about 85% greater than in diverted
<br />reaches. The area immediatelv below the
<br />power plant has been modified by human
<br />activity and has steep, stabilized banks. Ri-
<br />parian vegetation is dense and is domi-
<br />nated by exotic locust trees (RobInia pSi'udo-
<br />aCQcia L.). Few Fremont cottonwoods are
<br />present. perhaps becausE' of the modified
<br />streambank conditions combined with sea-
<br />sonal flow peaks that no longer coincide
<br />with the vernal cottonwood recruitment
<br />periods_
<br />
<br />3 II~
<br />
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