### A

## STUDY

## OFFlSHJMPlNGEMENT AND

## SCREENPASSAGE ATHANFORDGENERATINGPROJECT

# A

## PROGRESSREPORT

R. H.Gray T.L. Page E. G. Wolf M.j. Schneider

January1975

BATTELLE PACIFIC NORTHWEST LABORATORY

RICHLAND,WASHINGTON 99352

### EXECUTIVESUMMARY
A study of screen impingement and passage of fish 

### with 

### 1/4 and 1/8-in. traveling screen openings isbeing conducted by Battelle-Northwest Laboratories 

### atthe Hanford Generating Project 

### (HGP). The data from March 197.3 

### through June 

### 1974 are reported here. The objectives of 

### this 

### phase of 

### the study were: 

### To determine the species 

### and estimate the total 

### number 

### of fish 

### (particularly salmonid outmigrants) impinged and 'passed by 

### the HGP intake screening system.

. 

### locompare the effects of screen mesh size (l/&versus 1/4-in. openings) on the impingement and passage offish. 

### loestimate the percentage of the salmonid outm'grant population impinged 

### and passed by the HGP intake screens. Preliminary conclusions ofthis phase of the study are:

0

8
8 The intake of cooling water does 

### not pose a threat 

### to resident 

### nonsalmonid species. The greatest impact is to 0-age chinook salmon recently emerged from redds during April and May between HGP and Priest Rapids Dam. Estimated impingement losses are 

### 12times greater with 

### 1/8 than with 1/4-in. screen openings but represent less than 

### 1%of fry emerging 

### from redds between HGP and Priest Rapids 

### Dam. Estimated passage losses are similar with both size screen openings and may represent a maximum 

### of 9%of the fry emerging from redds between HGP and Priest Rapids 

### Dam. The impact of screen impingement isless 

### than screen passage. The combined impacts of screen impingement and passage are virtually the same with both size screen openings, and may represent 

### a maximum 

### of 9%of the fry emerging from redds between HGP and Priest Rapids 

### Dam and about 3%of total estimated number ofchinook outmigrants passing HGP. Fish too big 

### to pass through the screen openings are able 

### to enter the intake. Three alternative routes around the screens have been identified but gaps between the screen frames seen to be the most likely alternative route. Ongoing studies are addressing these problems. iii 0ACKNOWLEDGEMENTS
The authors wish 

### toexpress their appreciation 

### to the technical staff involved in the 

### data collection: 

### Mr. D. D. Dauble, 

### Mr. D. A. Neitzel, 

### Mr. E. W. Lusty, 

### Mr. K. 

### 0. Schwarzmiller, 

### Mr. R. W. Hanf, Jr., and Ms. N. M. Rosentretet- and 

### tothose 

### who graciously agreed 

### to review the manuscript: 

### Dr. R. F. Foster, 

### Dr. 

### B. E. Vaughan, Mr. J. B. Vetrano, 

### Mr. W. 1. Templeton, 

### Dr. C. 

### D. Becker, 

### Mr. D. G. 

### Watson, Dr. 1. 1. Eberhardt and 

### Dr. J. 

### M. Thomas. We alsowish 

### to thank the HGP operations and maintenance personnel, particularly 

### Mr. R. 

### B. Pettus 

### and 

### Mr. A. MacDonald, whose assistance was i

### nvaluabl

### e i

### n conducting thi

### s research.C



### CONTENTS
LIST 

### OF FIGURES 

## .................. LIST 

### OF TABLES 

## .................. INTRODUCTION 

## ................... THE 

### INTAKE STRUCTURE 

## ................ MATERIALS 

### AND METHODS 

## ................ Beach Seining Observations and Dip 

### Netting 

## ........ Traveling Screen Wash Samples 

## ............ Intake Samples

## .................. Experimental Re1

### eases 

## ............... RESULTS 

### AND DISCUSSION


### .PRELIMINARY FINDINGS 

## ........ Timing and Abundance 

### of Fish

### Near 

### HGP 

## ........... Impact 

## .................... Total Impact 

## .................. SUMMARY OF 

### PRELIMINARY CONCLUSIONS 

## ........... REFERENCES

## .................... APPENDIX A

.

### Common and ScientificNames of 

### Salmonids ana Non-Salmonids 

## ............. 

## . vi .vii 

### .1 .4 .10 .10 

### .11 *13 

### .14 .16 .16 .19 .43 .45 

### .47 .A. 1

V

### LIST

### OFFIGURES
1 Schematic of 

### HGP Intake Showing Berms Before 

### and After Removal 

## . . 

# . . . . . . . . . . 

# . . 

# . . . 

## . . 2 Aerial View of HGP Intake (right) and Outfall (left)

## . . . 

## . 5 Schematic of 

### HGP Water Intake,Structure 

# . . . . . 

## . . 

## . 6 Plan 

### View 

### of HGP Water Intake Structure


### . . 

## . . '.



### . 

## . . 7 

### Top 

### of Vertical Traveling Screen Showing Hinged ScreenPanels

. 

## . 

# . . 

## . . 

# . . 

# . . 

# . . 

# - . 

## . . . 8 Beach Seine and Rainbow Trout Release Locations

. 

## . . . . . 11 Screen Wash Collecting Trap 

## . 

# . . . 

## . . 

# . . . . . 

## . 12 The Number of Salmonids Impinged/Screen/hr 

### and Collected by Beach Seine Haul in 1973

# . . . . 

## . . . . . 22 9 The Number of Salmonids Impinged/Screen/hr and Collected by Beach Seine Haul in 1974 

## . . . . . . . 

## . . . . 

## . 26 

### 10 Sizes 

### of 0-Age Chinook Impinged and Collected by Beach Seine in 1973 

## . . . . 

## . . 

# . . 

# . . . 

## . . 

# . . 28 11 Sizes of 0-Age Chinook Impinged 

### and Collected by Beach Seine in 1974 

## . . . . . 

## . . 

# . . . . 

## . . . ~ 28 12 Percent of Released Fish in the Intake After Different P

umping Periods


### . 

## . . . . '.


## . . 

## . . . 

## . . . . 36 13 Estimates of0-Age Chinook Screen Passage for 1974

. 

## . . . . 

### 39 14 Schematic Through One Intake Wall Traveling Screen and "Z-Frame"


### . . . . . . . . . . . . 

### . . 

### . . . 41 15 Gaps Between Screen Frames

. 

### . .. 

## . . . . . . 

## . . . 

### .421 L

LIST

### OFTABLES


### 1 Salmonids and Non-Salmonids Collected by Weekly Beach Seining atFour Locations from 11April 1973Through 19

### June 1974. 

## . 17 2 Numbers and Sizes of Salmonids and Non-Salmonids Collected by 

### Weekly Beach Seining atFour Stations During 

### the 1973 and 1974 Downstream Migration 

## ........... 18 

### 3 Number and 

### Percent Composition

### of Fish Species Collected on 1/4-in. Traveling Screens 

### from 28March 1973Through 13February 1974 

## ................ 20 4 Number and 

### Percent Composition of Fish Species Collected on l/4-and 1/8-in. Traveling Screens from 14February Through 5 

### June 1974 

## .............. 21 5 Numbers and Sizes of Salmonids and Non-Salmonids Impinged 

### ,on 7/4-in. Traveling Screens from 28 March 1973Through 13February 1974 

## ...............23 6 

### Numbers and Sizes of Salmonids Impinged on 1/4- and 1/8-in. Traveling Screens from 14 February Through 5 

### June 1974. 

## .. 24 7 

### Number and Sizes of Non-Salmonids Impinged 

### on 1/4- and 1/8-in. Traveling 

### Screens from 14FebruaryThrough 5 

### June 1974.


## ................ 25 8 Numbers of Salmonids Impinged on 1/4- 

### and 1/8-in. Traveling Screens 

### Versus Time of Collection (0945-1945 and 1945-0945) from 14 February Through 5 J.une 1974


### ........29 9 Impingement and Passage of Previously Released Rainbow Trout 

### on 1/4- and 1/8-in. Traveling 

### Screens from 27 Through 30 March 1974


## ................ 31 10 Salmonids and Non-Salmonids Sampled Inside 

### the Intake Behind 1/4-!n. Traveling Screens from 29 March Through 23 July 1973


### ................ 33 11 Salmonids and Non-Salmonids Sampled Behind 1/4- and 

### 1/8-in.Traveling Screens from 6 March Through 31 May 1974.


### ................. 34 12 Numbers of Rainbow Trout Released and Recaptured Inside Intake After Different Pumping Durations


### ....... 35

vii

### LIST

### OFTABLES (contd)
13 

### Daily Numbers of 

### Chinook Salmon Sampled on and Behind 1/4­ and 1/8-in. Traveling Screens by 

### Fintrol and 

### Dip 

### Net During Spring 1974 

## ................. 38 

### 14 Summary of 

### Estimates Impacts 

### Due to Impingement and Passage of

### 0-Age Chinook Salmon with 

### 1/4- and 1/8-in. Screens 

### During 1973and 1974 

## ................ 39

viii

### INTRODUCTION

### A STUDYOFFISHIMPINGEMENTANDSCREEN PASSAGE ATHANFORDGENERATINGPROJECT

# -A PROGRESSREPORT

R. H.Gray T.L. Page E. C.Wolf M.1. Schneider

INTRODUCTION
In March 1973, Battelle-Pacific Northwest Laboratories 

### (BNW) began an ecological baseline survey of the Columbia 

### River in

### the vicinity ofthe Washington Pub1ic Power Supply System's (WPPSS) Hanford Generating Project (HGP), and an assessment of interactions between plant operations and 

### the biotic components ofthe river. This report 

### presents progress to date of that part of the study which evaluates the impact of cooling water intake on the Columbia River fish community. A number of juvenile chinook salmon were observed behind the HGP traveling screens in

### the Spring of 1973. Sampling 

### was initiated to determine the magnitude of fish impingement and screen passage. Sampling problems precluded enumeration of the actual number offish passing the screens during the 1973 spring outmigration of juvenile salmon. Nontheless, the species of fish passed and the time of year that passage occurred were determined. A more comprehensive evaluation of passage and impingement was accomplished in 1974. One factor that appeared to increase the congestion of juvenile s'almonids in front of the intake was 

### a forebay caused by berms 

### hat exte ded some distance into the river both up and downstream (Figure 1). A gyre within this forebay apparently increased the potential formult ple exposure of fry to impingement and screen passage. To mitigate the impact of the intake 

### on outmigrating salmon, the Washington State.Department of

1

# ------ COLUMBIA RIVEi3 FLOW \ / I \ I \



### BEFOREBERMREMOVAL AFTER BERMREMOVAL

FIGURE 

### 1. Schematic of 

### HGP Intake 

### Showing Berms Before 

### and After Removal
Fisheries requested 

### that the intake forebay be modified 

### by removing the berms before the 1973 spawning season. Berm removal was accomplished 

### in September 1973and apparently diminished the gyre 

### infront on the pumphouse. Another factor 

### that appeared 

### to exacerbate fish passage through the traveling screens was the 1/4-in. size

### of the screen openings. The 

### travefing screens were 

### not specifically designed as fish barriers, but 

### to protect the circulating water system from particulate material in the water. As originally designed, the screens were only partially.effective in excluding fish. Therefore, 

### to reduce passage, the Washington State Department of Fisheries requested that the size of the screen openings be reduced 

### to 1/8-in. before the next salmonid outmigration. In February 1974, WPPSS began changing the traveling screen mesh 

### from 1/4 

### to 1/8-in. openings. However, inresponse to a request by BNW and WPPSS, the State Department of Fisheries agreed to leave one-half of the traveling screens unchanged. This action afforded the opportunity for direct comparison of impingement and passage of fish with the 

### two different traveling screen openings. A research program was designed with the following objectives:

# I

.

0 To determine the species 

### and estimate the total number of fish 

### (particularly salmonid outmigrants) impinged and passed by the HGP intake screening system. To compare the effects of screen mesh size (l/&versus 1/4-in. openings) on the impingement and passage of fish. To estimate the percentage of the salmonid outmigrant population impinged 

### and passed by the HGP intake screens.

3

## ’. 4

THEINTAKESTRUCTURE

### THEINTAKE

### STRUCTURE Washington Public 

### Powzr Supply System's 

### HGP is located at Columbia River Mile 380 next 

### to the Atomic Energy Commission's N Reactor. The 

### pumphouse 

### is 

### a typical bankside, shoreline installation (Figure 2). The site for the intake structure 

### was excavated to 

### about 70 ftbelow the normal river 

### bottom and extends into the river for 

### 75 

### to 125ft. 

### Atdesign low flow (36,000 cfs), the water in 

### front of the intake is 

### about 20 ftdeep. Itater entering the coolinq system 

### from the river firstpasses 

### through coarse trash racks, which consist of 

### 5- by 

### 1/2-in. vertical steel grates which are 3 

### 7/4 in. 

### apart (Figure 3). A curtain wall behind the trash racks extend 

### to within 22 ftof the 

### bottom and is 3 

### to 5 ftbelow the water surface for most 

### of the year. Vertical traveling screens are located There are 

### 6 screen bays (Figure 

### 4), abwt8 ftbehind the curtain wall. each with 

### a 

### row of vertical screens. Each vertical row consists of 

### a series r,f panels, 10

### ftby 2 ft, hinged into 

### a continuous chain (Figure 5). The panels are made of staipless steel mesh, originally with 1/4-in. openings. Trash collected 

### on the screens is lifted vertically 

### to the 

### top of L~G structure by screen rotation where 

### a high pressure spray (80psi) cashes impinged material into a trough (Figure 3) and returns itvia a sl:;ice-i.iay and pipe 

### to the river downstream of the plant (Figure 

### 2}. Internally, 

### the intake pirmphouse isdivided into 

### two replicate halves, eti::? with

### two 141,000 gpm ?amps drawing water through three vertical rows vf trzveling screens (Figgre 4). The total pumping,capacity of both halves
1s CjF,4,00@ gpni. The desi23 approach velocity (measured values are 

### not ?:z;lable) infront of the screefis is less than 1 fps. However, the actual i 1 ~ ~ ~ ~ ~ ~ ~ : velocity

~ is inot\the approach velocity, but rather the velocity . .

. tii:-(:!dgh the screefi mesh itself. The calculated velocity through the

L'reens is 1.95 fp; 

### atminimus water level for the 1/4-in. opening screens(1

### 1

:.it(.: x.35 fils through the sr.aller 1-8 in. screens. Since throughol;t
c;. ,:>I. all of the study period the river exceeded minimum low flow, the i!.,:iir:ging velo-,itics IO wtiich the fish 

### were exposed were less 

### than these

. > : !:cL, i2ted vtil~c3.



### 4U t tw

>o n 7 a3

I - F 0 L Q: L Q

w W CY 3 a W LLI 

# /

I



### FIGURE 3. Schematic of HGP Water Intake Structure

6C

I +-cow* , fCpuyps

TRASH RA

I TO COUDENSLRS 

## I 

# 1

?UNCI

FIGURE 4. Plan View of HGP Water Intake Structure

78

### During 

### the spring of 1974, one-half of 

### the 6 vertical rows of travel

### ing screens 

### were changed to 1/8-in. openings. By rotating 

### the screens 

### either 1/4- or 1/8-in. openings could be placed 

### inthe water. 

### On the upstream (No. 2) side of 

### the intake, 1/8-in. openings were 

### in

### the water at all times. For comparison, on 

### the downstream 

### (No. 1) side, screens with 1/4-in. openings remained 

### in the water throughout most of' the 1974 salmon 

### o

### utini

### gra

### tion

# .

9a 1

MATERIALSANDMETHODS

### -- MATERIALSANDMETHODS
The segment of the impingement and passage sampling program discussed below 

### was initiated in late March 1973 and continued 

### through mid-June 1974. Beach1 seine samples and visual observations 

### and dipnetting of the intake forebay were included 

### inthe investigative program to determine the 

### timing and abundance of salmon outmigrants emerging from spawning redds upriver from 

### the intake and the movement of resident fish species. Samples of the traveling screen washings 

### and from inside the intake were obtained 

### toestimate the magnitude of impingement on 

### the screens and passage through the screens. All of the above samples were collected 

### on a routine 

### basis except when' 

### the screen 

### wash sampling schedule was interrupted by the annual summer maintenance outage during June 

### and July 1973. Controlled experimental releases of rainbow 

### trout (Salmo gairdneri)(a)were made 

### in

### the river during March 1974 to simulate downstream migration. Samples 

### to detect these fish were taken from the screen 

### wash and inside the intake behind screens of both sizes. Releases were also made inside the intake 

### asa check 

### on sampling effic ency and 

### to estimate residence time once f 

### sh were insidi. the intake. All fish collected were identified 

### to species where possible, measured and preserved in 10%formalin. A few impinged fish were 

### too badly mutilated 

### or decomposed 

### to be identified. A number of sucker fry (Catostomus spp.) collected by beach seine (July-September 1973) could only be identified to genus.
BeachSeiningObservationsand Dip Netting Weekly beach seining was carried 

### out from 11 April 1973 

### through 19June 1974

### atfour locations in the river with 

### a 30-ft net of 1/8-in. mesh. 

### Two stations were located 

### on each side 

### of the river, 

### so that

### two

(a) Scientific and common names of all fish mentioned inthis report are listed in Appendix A. .

10

### -- 

### were above and 

### two were below 

### the intake (Figure 

### 6). 

### Dai y observat 

### ons and 

### dip

### netting of

### the intake and forebay 

### water were made 

### during 

### the salmon outmigration.

UTRELEASEPOINT

3.. i IcCC

.<­ --. 1_---- t FIGURE 

### 6. Beach Seine and Rainbow 

### Trout Release Locations
TravelingScreenWash Samples Traveling screen wash samples were obtained on odd 

### number calendar working days throughout most ofthe study period from 

### 28 March 1973 through 

### 19April 

### 1974. Samples were collected dailyduring 

### the work week from 21 April to 5 June 1974. The traveling screens 

### atHGP are usually washed for approximately 20 min daily

### duringmost of theyear. However, during the 

### spring freshet when large amounts of particulate matter are suspended in

### the water, the screens arewashed twice daily. This latter schedule usually begins 

### in mid-April and continues until late May when the plant ceases operation for summer maintenance. The 20 min morning 

### wash routinely occurs between 0830 and 1100 hr. During the spring freshet, the additional 20 min evening wash occurs between 1800 and 2130 hr. 

### During this study, the morning wash was conducted at0945 hr. The time of the evening wash was more variable, but usually took place about 1945 hr. In order to collect screen washings, a 

### trap (Figure 7) was inserted into the trash return sluice-way. From 28 March 1973to-14February 1974,

11e 1L

t when the traveling screens all had 1/4-in. openings, the 

### trap was lined 

### with 1/4-in. mesh screen. 

### From 14 February 1974 

### until the termination of the study, 

### when the intake had both 

### 1/4- and 

### 1/8-in. traveling screens, the trap was lined with 1/8-in. mesh screen. When two screen sizes were 

### in

### use, each was washed separately on each sample date. From 

### 1 April through 15 

### April 1974, atthe 

### request of the Washington State Department of F-isheries, all intake screens had the smaller 1/8-in. openings 

### inthe water. 

### During this period 

### an evaluation by the 

### Department of Fisheries of the program resulted 

### intheir allowing the comparison of 

### 1/4- and 

### 1/8-in. screen impingement and passage to continue. Therefore, 

### atall other times during the 1974outmigration both 

### 1/4- 

### (No. 1 side) and 

### 1/8.-in. (No. 

### 2 side) openings were in the water and comparative samples were collected. Once a sample 

### was collected, the 

### trash

### was hand-sorted, fish were identified, and their condition noted. 

### Fish from morning screen wash samples that exhibited either body 

### or opercular movements were placed 

### inan aquarium 

### suppliedwith running river 

### water. Atthe end 

### of.24 

### hr the number of dead and living fish, determined by opercular movement, was recorded.
intakeSamples Several sampling schemes were considered 

### or tried for collecting fish passing the traveling screens during normal plant operation. Most of these schemes were unsuccessful due 

### to the internal configuration of the intake, the large volumes of water pumped, and the need to provide complete safety 

### for research personnel and not endanger steam plant operations. The successful sampling schemes are discussed below. To assess the number, species 

### and size of fish 

### thatpassed through the traveling screens during the initial phase of the passage program (29March 1973 .through 

### 13February 1974), dip netting 

### was conducted inside the No. 1 side of the intake (only 1/4-in. screens were installed inthe plant at this time). 

### On 23 July 1973, during the beginning of the annual summer maintenance outage, Fintrol 

### 5, a commercial fish toxicant 

### was used 

### to assist in collecting and quantifying the number of fish passing the

13traveling screens. 

### The 

### water inside 

### the 

### intake was 

### treated with 1 gal 

### (8lb

### 4 02) of 

### Fintrol 5 before dip netting. The active ingredient of 

### Fintrol 5, antimycin A, 

### is absorbed into the gills of fish, interferes 

### with respiration and eventually results 

### indeath. 

### Fish

### exposed 

### to Fintrol 

### 5 

### swim slowly 

### tothe surface and are easily collected, 

### Dip 

### netting after poisoning 

### continued for 

### an average of 

### 2.5 

### hr. 

### For the remainder of the period when there were 

### two screen sizes (14 February 1974 throuqh 

### 5 June 1974), 

### dip netting 

### was continued and quantification of effort attempted 

### inside both 

### sides of 

### the intake. To 

### provide 

### a comparison of the daily variation 

### innumbers of fish entering the intake structure through both size screens, records of the length of time spent dipping 

### (1 through 8 May) 

### and the number of 

### dips (9

### through 24 May) were kept. Samples from both sides.of the intake were 

### also collected using Fintrol 

### 5 

### on several occasions from late March through late Play 

### during the 1974 salmon outmigration. The 

### pumps 

### must be off 

### inorder to sample effectively with Fintrol 5 since pumping will result inrapid dilution of the chemical, thus making itineffective. Therefore, samples were collected during either scheduled or unscheduled plant outages. 

### Experimental

### Releases Experimental releases of rainbow trout (Salmo gairdneri) were made in late March 

### 1974. Rainbow 

### trout were used because of their immediate av~itr;la.­ bility. Prior notice of the outage timing was insufficient 

### toprocure other salmonid species. Since the released fish were the only rainbow fry in the vicinity of HGP 

### atthis time, they constituted 

### an easily identifiable experimental population. 

### Two sub-groups of rainbow fry were established by cold branding 

### on the 

### right 

### or left side above the lateral line. After branding, fish were held inthe laboratory for 

### a minimum of three days 

### to insure recovery before they were transported tothe site. 

### Thus, three experimental populations were established for these studies: unmarked fish, branded leftside, branded rightside.

14

### To estimate the portionof a given population of fish passing a specific point inthe riverthat might be impinged or passed by the HGP intakewith either 1/8- or 1/4-in. screen openings, 20,000 unmarked rainbow frywere released near shore 500 to 600 yd upstream of the intake (Figure 6). This distance was considered to be sufficient for the released fishto orient to rivercurrents before reaching the intake. Visual observation of released fish showed that they immediately oriented to the current and confirmed this assumption. Following the experimental release, the screen wash and intake bays were sampled daily. To estimate the number of fish that might be impinged or passed once behind the curtainwall, cold branded (left side) fishwere planted inthe six bays immediately infront of the traveling screens. Releases behind the curtainwall totaled 2400 juvenile rainbow infront of the 1/4-in. screens (No. 1 side) and 2098 infront of the 1/8-in. screens (No. 2 side) The screen wash was then sampled twice daily to estimate impingement of branded fish. The water inside the intakewas poisoned one day later to define passage of branded fish through the screens. Differences between passage and impingement by the two d fferent size screens were then compared. Releases of cold branded (right side) rainbow trout were made behind the traveling screens (inboth the 

### No. 1 and 

### No. 2 sides) to estimate the residence time of fish, inside the intake after a known pumping duration. Any subsequent appearance of these fish inthe screen wash would indicate that they passed from behind the screens tothe river side and then became impinged. Atthe time ofthese releases, the 

### No. 1 side had 1/4-in. screens inthe water while the No. 2 side was fittedwith 1/8-in. screens. Three seDarate releases were made behind the screens. They consisted of 1500, 1158 and 1150juvenile rainbow trout. The fishwere sampled by Fintrol and dipnet after pumping periods of different lengths. Additionally, another 1000 juvenile rainbow were released inside the intake and sampled imnediately (i.e., no pumping) to test the efficiency of the Fintrol sample method.

15* 7

RESULTSAND DISCUSSION

# - PRELIMINARY FINDINGS,



### RESULTSANDDISCUSSION

# - PRELIMENARY FINDINGS Timingand Abundance

### of 

### Fish NearHGP Chinook salmon (Oncorhynchus tshawytscha) made 

### up 99.5%of the salmonid

. catch and 32.2%of 

### the total catc'h from all stations inweekly beach seine hauls between 

### 11 April 1973 and 

### 19June 1974 (Table 

### 1). In 1973,juvenile salmon (mean fork lengths, range 4.0-5.4 cm) appeared 

### ingreatest 

### numbers in April and May (Table 

### 2). In 1974, juvenile salmon (mean fork lengths, range 4.2-5.4 cm) 

### were 

### most abundant from May 

### through 

### the firstpart of June (Table 2). That 

### is, the major portion of 

### the salmon outmigration occurred later in 1974 than itdid in 1973. The 

### most common non-salmonid species collected 

### were the redside shiner (Richardsonius balteatus), northern squawfish (Ptychocheilus oregonensis) and sucker fry (Catostomus spp.)

## - Other species of fish were collected less frequently (Table 

### 1). Nonsalmonids were collected 

### in

### greatest numbers from mid 

### to lateMay inboth years (Table 

### 2). Peak migration of 0-age chinook salmon past Priest Rapids Dam occurs in

### August.(3) Chinook from hatcheries and spawning channels (fork length 8-10 cm) are released from mid-May 

### toJuly. Naturally spawned Hanford chinook, however, still maintain the .historical migration pattern. Outmigration generally begins inmid-March and peaks 

### from April through June with fish averaging 4.1-4.9 cm (fork length). Sythe end of July most Hanford spawned chinook have apparently departed the area.

### (4) The timing of the 1973 and 1974 chinook outmigration,and the sizes of the fish reported here also agree with the historical migration 

### pattern, indicating that fish collected by beach seine are offspring 

### of adults spawning in the fall in the Hanford area. Fish produced 

### from redds, hatcheries and spawning channels upriver from Priest Rapids Dam appear later in the year when the plant is usual'ly 

### shut down for maintenance. These fish are also larger when they pass through the Hanford area and, therefore, less likely 

### to be affected by HGP pumping operations.

16

### --

-- -- TABLE 1. Salmonids and Non-Salmonids Collected by 

### Weekly Beach Seining atFour locations 

### from 11 April 1973Through 19

### June 1974 Total 

### No. % Total SALMONIDS Oncorhynchus 

### ts hawyt

### scha (Wal'baum) 'I359 32.2 Prosopium williamsoni (Girard) 3 0.1

- 0. nerka (Walbaum) 2

- 

### 0. kisutch (Walbaum) 1 Salmo gairdneri Richardson 1 Total Salmonids 1366 32.3 i\lON- SALMOti

### IDS Richardsonius balteatus

I(Richardson) 1257 29.8 Ptychochei

### 1

### us oregonensi

### s (Richardson) 710 16.8

I_ Ca

### tostomus fry 632 15.

## c Mylocheilus caurinus (Richardson) 173 4.1 Catostornus macrocheilus Girard 55 1.4

- -___­ -_ - Gasterosteus aculeatus Linnaeus 4 0.1 Cottus 3sper Richardson 

### 4 0.1

___- Cottus rhotneus (Srnith) 

### 4 0.1 Acrocheilus alutaceus Aqaqc;iz & Pickering 4 3.1 ____-_

.- Cottus perpl

### exus Gi1bert & tverrnann 1 Lepomis gibbosus (Linnaeus) 1

- -__­

_____ -. (Valenciennes) * l Rhinict& dataractae

- - R. falcatus Eigenmann 8 Eigenmann 1 Cyprinus carpio Linnaeus 1 Total Non-Salnionids 2851 67.5 Total Fish 4217

17L



### TABLE



### - 2. 

### Numbers and Sizes of

### Salmonids and Non-Salmonids Collected by 

### Weekly Beach Seining at Four Stations During the 1973 

### and 

### 1974 Downstream Migration

Sa1monids Non-Sa1monids Fork Lengk Fork Length1973 No. Hauls Total No. No/

__ Haul ALg. Range



### - (cm) (cm) Total 

### No. NO/

- Haul Avg. Range

__ 

### (4 (cm) April 6 129 21.5 4.7 3.5-16.0 2 0.3 3.6 2.2-5.0 1-21 22-30 8 69 8.6

, 5.4 3.4-14.5 1 0.1. 2.5 May 1-7 0 8-1!5 8 44 5.5 4.0 3.5-4.8 1 0.1 1.8 16-25 4 80 20.0 5.0 3.6-21.4 188

. 47.0 5.5 2.7-49.3 26-31 4 115 28.8 5.2 3.6-7.6 117 29.3 6.8 4.0-9.6 June 4 23 5.8 6.2 4.0-12.5 3 0.8 18.7 8.1-37.5 1-8 9-13 4 13 3.3 7.9 4.1-15.7 0 

## - - 

## - 1974 March 8 8 1.0 5.5 3.5-16.1 2 0.3 4.0 3.0-4.9 1-15 16-21 4 9 2.3 11.5 3.8-31.5 5 1.3 3.9 2.7-5.4 22-31 4 9 2.3 8.3 3.7-29.5 10 2.5 5.4 3.1-12.7 Rpri1 4 4 1.0 4.2 3.7-5.1 4 1.0 5.1 3.3-7.2 1-7 8-15 8 45 5.6 4.4 3.7-10.3 3 0.4 4.4 3.7-5.2 22-30 4 9 2.3 4.0 3.9-4.3 7 1.8 5.0 4.6-7.2 hY 4 46 11.5 4.2 3.8-4.6 2 0.5 5.2 4.0-6.3 1-7 8-15 8 244 30.5 4.2 3.6-5.2 15 1.9 5.7 3.0-14.0 16-22 4 io5 26.3 4.4 3.7-5.4 352 88.0 4.6 2.5-10.3 23-31 4 62 15.5 4.6 3.8-5.5 1 ' 0.3 4.7 

### - June 4 142 35.5 4.8 3.5-6.6 6 1.5 5.3 4.7-6.8 1-8 9-15 4 139 34.8 5.4 3.8-7.3 2 0.5 25.0 4.1-45.8 16-22 4 51 12.8 5.4 3.8-7.8 19 4.8 8.2 5.8-13.2 

### - - - - - 

## - - 

# ­

18These observations indicate that the salmonids 

### most susceptible 

### to screen impingement and passage 

### atHGP arejuvenile fall chinook spawned between the intake 

### and Priest Rapids 

### Dam. This conclusion 

### is supported by the appearance 

### of juvenile chinook salmon on and behind the traveling screens from mid-March through May (see IMPACT). The time of appearance and size of these fish indicate that they belong 

### almost exclusively 

### to the 

### O-age class and that they originate between Hanford and 

### Priest Rapids Dam. Daily observations and dipnetting of 

### the intake forebay water 

### through

### out the study period indicated 

### that salmonid fry and smolts were more abundant during 1973 than 

### in 1974. The fewer salmonids observed 

### in the forebay during 1974 may have resulted from 

### berm removal, but our ability to see the fish was influenced in 

### 1974by factors such as increased river runoff and water turbidity. Impact Impingement 

### on the Traveling Screens 

### Four salmonids and 

### 11 non-salmonid species totaling 243 fish were collected on the 

### 1/4 in. traveling screens 

### from 28 

### March 1973 through 13

### February 1974 (Table 3). Chinook salmon (Oncorhynchus tshawytscha) accounted for 57.6d of the fish impinged and 96.6%of the salmonids impinged. The threespined stickleback (Gasterosteus aculeatus), redside shiner (Richardsoni!Js balteatus) and peamouth chub (Mylocheilus caurinus) were the most common non-salmonids impinged. Other species were impinged less frequently. From 13 February through 5 June 1974 chinook salmon were the only salmonids impinged on either size traveling screens (Table 4). This species iiiade up 78.3%of 276 identifiable fish impinged 

### on 1/4-in. screens and 

### 90.9’:of 2637 identifiable fish impinged on 1/8-in. screens. Ten species of non-salmonid fish were impinged on both 1/4- and 1/8 in. screens. Three additional non-salmonid species (total 13)were impinged 

### on 1/8-in. screens. In 1974, the three-spined stickleback again 

### was the predominant non-salmonid impinged on either 1/4 

### or 1/8-in. traveling screens. The reside shiner--- -

----

-- --- 

### TABLE 3. Number and Percent Composition 

### of Fish Species Collected on 1/4 

### in. Traveling Screens from 

### 28 March 1973Through 13February 1974

SALMONIDS Oncorhynchus -__­ tshawytscha (Walbaum) Prosopium williamsoni
- (Girard) 

### 0. kisutch (Walbaum)

-. A­

- 0..nerka (Walbaum) Total Salmonids
NON-SALMON

### IDS Gasterosteus aculeatus Linnaeus

___ __-- Total % 

### of Total No. 

### Fish Collected

140 57.6 3 1.2 1 

### .4 1 

### .4 145 59.8

Richardsonius balteatus -__ -. -- _______ (Richardson) Mylocheilus caurinus

-__ - (Richardson) Cottus asper Richardson

~ Catostomus macrocheilus Girard

- ..- --- Entosphenus tridentatus (Gairdner)

--_-

___- -_ -_- Alosa sapidissima (Wi1son)

- -__- -. 31 12.8 19 7.8 19 7.8

8 3.3 7 2.9 4 1.G 4 1.6

~ - --___ -. __- Cottus beldingi Eigenmann 8 Eiqenman 1 

### .4

- -~

. Ptychocheilus oreEensis (gichardson) 3 1.2 Cyprinus c.arpio Linnaeus ' 

### .4 Perca flavescens (Plitchi11) 

### -4

- - Total Non-Salmonids 98 40.3 Total Fish 243

20

### TABLE 4. Number and Percent Composition of Fish Species Collected on llband7/8-in. Traveling Screens from 14 February Through 5 June 1974



### - 1/4- in. Screens 1

### /8- in. Screens


### X of

### Total % of

### Total Total Identifiable .Total Identifiable

No. 

### Fish Collected 

### No. Fish Collected _- 

### SALMON1DS Oncorhynchus tshawytscha (Walbaum) 216 78.3 

### 2398 90.9 

### NON-SALMONIDS 

### Gasterosteusaculeatus Linnaeus 21 7.6 85 3.2 

### Richardsoniusbalteatus (Richardson) 13 4.7 32 

### 1.2 Cottus asper Richardson 7 2.5 24 .9 

### Ptychocheilusoregonensis (Richardson)5 1.8 46 1.7 

### Cottus bairdi Girard



### -~ 3 

### 1.1 6 .2 

### CatastomusmacrocheilusGirard 3 1.1 

### 14 .5 

### Mylocheilus 

### -caurinus Richardson 3 1.1 

### 12 .5 

### Entosphenus tridentatus (Gairdner) 2 .7 

### 12 .5 

### Cottus beldingi Eigenmann & 

### Eigenmann 2 .7 ' 1 .4 

### Percopsis transmontana (Eigenmann& 

### 1 

### .4 4 .2 

### Ei

### genmann) Cottus rhotheus (Smith) 

### 1 Cyrpinus Carpio Linnaeus 1 

### Acipenser transmontanusRichardson
- - 

### - 1

-__ 

### Total Non-Salmonids 60 21.8 239 9.0 

### UNIDENTIFIABLE 22 7.4' 47 1.a1 

### Total Fish 298 2684
% of 

### total number of fish

### collected(Richardsonius balteatus)

### ,prickly sculpin 

### (Cottus asper) and northern squawfish (Ptychochei

### 1

### us oregonensis) were the next three most common nonsalmonids impinged. Other non-salmonid species were again represented less frequently on both 

### 1/4- and 1/8-in. screens. In 1973, the greatest impingement 

### of both salmonids and non-salmonids 

### on 1/4-in. traveling screens occurred between late April and mid-May (Figure 

### 8, Table 

### 5). The size of impinged 

### fish ranged from 2.3-71.5 cm fork length. Approximately half of the fish larger 

### than 10 cm and 

### a few smaller fish were decomposing indicating 

### thatdeath had occurred prior to impingement. Fish as large as 38.2 cm (gravid female whitefish) and apparently in good condition were also impinged. Comparison 

### of the average 

### sustained swim speeds (i.e., > 3 fps) 

### of these larger fish(5)to the calculated water velocity 

### of 1.95 fps through 1/4-in. screens 

### atminimum low water indicates that they were severely stressed (i-e.,disease), or were dead before impingement.
a500 1973



## -BEACH SEINE 

### -__-- SCREE&WASH 114 INCH

003c --LF-Li~-- JAlvUARY FEBRUARY WARCCI’ APRIL WY JUNE FIGURE 8. The Number of Salmonids Irnpinged/Screen/hr and Collected by Beach Seine Haul in 1973

22

### TABLE 5. Numbers and 

### Sizes of

### Salmonids and Non-Salmonids Impinged on 7/4-in. 

### ra

### ve7 ng 

### Screens from28 

### March 7973 Through

.

### 13 

### February 

### 1974

Salmonids Non-Salmonids Sampl i ng Effort

(hr) Fork Length No-1 

### ‘la) Total Screen/ Avg. Range

No. hr Total 

### No. fork Length No./ screen/(a) Avg

### . :,ax.:

hr (cm) (irn) March 48 0 

### .0000 

### - - 1 .0035 5.5 - Apri1 220 6 ’ -0045 3.8 3.3-4.0 16 .0121 5.6 2.3-14 1 1-21 Apri1 22-30 28 18 .lo71 4.6 3.2-9.5 9 .0536 4.7 3.2-6. May 1-7 42 

### 61 .2421 5.3 3.5-9.2 17 .0675 4.7 3.5-71 5 May 8-15 42 44 .1746 5.1 3.5-19.4 2 .0079 16.8 4.3-29.3 May 16-25 56 2 .0060 4.9 4.6-5.1 2 .0060. 4.2 3.9-4.4 June(b) July(b) August 168 1 .OOl0 38.2 - 3 .0030 17.7 15.8-19.5 September Oct ober 264 72 1 0 .0060

.0000 43.3



### - -

- 15 15 .0095 .0035 6.3 5.3 3.3-19.8 4.5-8.9 November 120 8 .OD11 51.9 38.9-71-5 2 .0028 3.6 3.0-4.1 December I20 1 .0014 29.3 

### - 2 -0028 5.4 5.1-5.5 January 168 0 .oooo 

### - - 6 .0060 8.6 3.6-14.7 February 1-13 96 2 .0035 6.3 3.9-8.7 9 .0156 6.3 4.2-10.0

(8)Six vertical rows of traveling screens were washed on each sample date. (b) Plant shutdown for annual summer maintenance.

Number and size of all fish impinged per screen per hour on 1/4- and 7/8-in. screens from 14 February through 5 June 1974 are shown inTables 6 and 7. Dlrring this period, non-decomposed larger (up to 52.0 cm) fish were impinged on both size meshes. Again, based 

### on capable sustained swim speeds and the calculated velocity through the screens (2.36 fps with 1/8-in. openings atminimum low water), itis unlikely that these fish were impinged without experiencing some debilitating preimpingement event.

23I

I

0 0 0 0

I

- i
0 SZ om 3 -or0 aJL mt SI­ 0 cu 05 Lo

*- aJ I i SLL 0 Eb c3 cr

I Ln I m OG
mm wc h a m m

Ln 7 N W c 7 c 0
I

- I n: . 3 - s c 3 c­ ozt0 33

13

v

h I Ln h I

24h

v 

# f j 0 

# !

I . . . . . , S d.j-fmlnCn -r

I a2 m 1 ./I c ON* Q Ncncu Ln bhNLn mmo0



### . . .7 I

Ohhm Lnw N

C O O N cu ewm h

.. 

# - mm -7 7 I 1 I 1 I CON

.. N NLO m -3-0 aJaJ lns CON

&E X U zo maJ om om ~n ul .... I ln3 am corn cul w WCC LO

CO-NmOLnO m--c~moho ioem~moo 0000000

....... j UU 1 I +s om

u3 I. -.

1 c - 

## - N a

25Y The sampling technique was not conducive tocollecting impinged fish alive. Fish could be impinged for several hours before being washed into the collection basket. Live-dead counts for morning samples indicatethat about 6%ofall fish impinged on 1/4-in. screens in1974 were alive atthe time of collection. Approximately 1%of all fish impinged on 1/8-in. screens were collectedalive during this period. Though these estimates of live impingement may be low, nonetheless comparison.of survival between the two screen sizes isreasonable. The data do indicate the percent offishthat might be expected to survive impingement on both size screens under the present screen wash regime. 

### In 1974, peak chinook impingement on the 1/4-in. screens occurred from lateApril through early May (Tsable 6, Figure 9). However, peak chinook impingement on 1/8-in. screens shifted tomid-May was up to 200 times greater than impingement on 1/4-in. screens.’ Additionally, there was an early impingement peak inMarch and April on 1/8-in. traveling screens that did not occur on 1/4-in. screens. This clearly indicated that 1/8-in. screens resulted in greater impingement of chinook outmigrants over a longer period.

1914



## -BEACH SCINE -----SCREEN WASH lld INCH



### --SCREEN WASH 1R INCH 18

16

14

12

10

## r

rn a w g m

5 z
6
4 4

2

0 JANUARY FEBRUARY MARCH APRIL MAY JUNE 

### FIGURE 9. The Number of Salmonids Impinged/Screen/hr and Collected by Beach Seine Haul in 1974

26The 

### timing and maximum abundance 

### of 0-age chinook impinged on 1/4-in. screens 

### in 1973 

### and on 

### 7/4- and 1/8-in. screens in 1974 occurred before 

### maximum catches collected by beach seine 

### (Figures 8 and 9). This is probably a function of fish size. The fish collected by beach seine after impingement had declined to zero were older, larger, and more capable of avoiding intake approach velocities butnot beach seine hauls. The average size (i.e.¶ fork length) of impinged 0-age chinook are compared with those of 0-age chinook collected by beach seine inFigures 10 

### and 

### 11. As average size increased during early June in beach seine samples (Figures 10 and ll), salmon impingement fell 

### tonear zero on both 1/4- and 

### 1/8-in. screens (Tables 

### 5 and 

### 6). The early impingement 

### that occurred 

### on 1/8-in. traveling screens in 

### 1974 and the greater numbers impinged 

### was probably due 

### tothe smaller openings and the higher approach velocities. Average sizes of impinged salmon did not differ between 1/4- and 1/8-in. screens (Table 

### 6), nor did average size of salmon impinged in 1973 differ from those impinged on the 1/4-in. screens 

### in 1974 (Tables 5 

### and 6). According to Mains and Smith,(6) 0-age chinook move through the Hanfot-d reach of the Columbia River mainly 

### atnight. More than 70%of their catch was made between 1800 and 0600 hrwith peak numbers between 0300 and 0600 hr. Our results indicate that impingement may be greater during the day (0945­ 1945 hr) than 

### atnight (1945-0945 hr) 

### on traveling screens of both sizes (Table 8). This may be the result of congregation of 0-age chinook juveniles in shoreline feeding area (i.e., around the intake and intake forebay) 

### ?c:?­ ing the day. Estimates of Total Impingement Estimates of total impingement during the 1973and 1974 outmigration can be obtained from the number of fish impinged per screen per hour (Tables 5 and 6). Multiplication 

### of these values by the number of screens (6)and the number of hours ina day (24) gives the number offish impiEg?d daily. Each of the values isthen multiplied by the number of days in each of the period reported. Finally, the number of fish in each period (Tables 5 and 6) is summed over the entire impingement season to obtain an estimate of the total number of fish impinged.
27

# ------

---

--

# ------It)> 

### 60

f 

### 55



# - E



### 35 

### 30

65 60 E � 

### 55 1 c 0 

### 510 z

I.. -1 2 

### 45 Cc 0 

### 40 

### - 1973 BEACH SEINE

- 

### SCREENWASH 114 INCH

-

I I 

### I I I



### JANUARY FEBRUARY MARCH APRIL MAY ' 

### JUNE



### FIGURE 10. 

### Sizes of 

### 0-Age Chinook Impinged and Collected by 

### Beach Seine in 1973

.



### 1974



### - BEACH SEINE

- 

### SCREENWASH 114 INCH SCREEN WASH 

### 1/8 INCH



### - 35 I" 

### 30 L L l I I 

### JANUARY FEBRUARY MARCH APRIL MAY JUNE 

### FIGURE 11. 

### Sizes of 

### 0-Age Chinook Impinged and Collected by 

### Beach Seine in 

### 1974

28h

0 00- In d h m -0 0 h oom al m VI 0 -0 0 m 000Ln h m In I coo 0 Ln 

### ?Y'l 0 In 

### 9 m Nh 0 '4 

# .. .- mm

In b m h I Wrn 0 

# - e 0 hm 7 m "

h cn m m om 0 W 43 m a h om 0 u co m

# - 0 em 0



## ... 0 '4 cu e h 

### ?d: 0 

# - cu me

-ha mh d d h h W cum 0 0 h f-m m In e ­

oom N m coin e 00- In 

# z o mcu 

# z 0 0 0 00'5 I I m N d Nd cu h



## ... 0 ? cu 

### 99 9 0

u ma L -0-e W OCN I I d m N cum .- c, W 

# s c -C

00- m N 0 om0 0 c 00- m Lo om0 0 00- I 1 03 Ln 0 omco 0 000 0 ID

# - 000

- 0 

### ... 

## ...

00- I I In d 

# -- 0-W 0
7

>. Ln L fi I a I c 3 7 0 7 L cu m a n I I E aJ W N a 3 LL 

# - cu IT 3

29

### 1973

### Season: By this 

### method about 

### 600 0-age chinook salmon are 

### estimated to have been impinged on 1/4-in. traveling screens 

### during the 1973 outmigration. 

### The total number of chinook outmigrants 

### from upriver passing the 

### HGP intake in 1973 is estimated by the Washington 

### StateDepartment of Fisheries 

### to have been 

### 2.1 million.(7) Most (1.86 million) of these came from natural spawning or spawnin? channels above or atPriest Rapids Dam. The remainder (0.24 million) represent emergent fry from fall chinook spawned between Priest Rapids Dam and the intake. This estimate, however, based 

### on 1972 aerial 

### redd 

### counts may be low because of adverse weather conditions contributing 

### topoor visibility 

### during 

### the aerial surveys.

### (8) 

### The estimated 

### 600 fish impinged on 1/4 

### in. traveling screens, 

### in 1973, represent 

### 0.3%of the estimated outmigration emerging between 

### HGP and Priest Rapids Dam. 1974 Season: The values inTable 

### 6 (i.e., number 

### of salmonids impinged/ screedhour) can be used to estimate the number of chinook salmon impinged during the 1974 outmigration if the entire intake had screens of only one size. Impingement losses were estimated 

### to be at least 1200 fish with 

### 1/4 and 14,278 fish with 1/8-in. screens. Total impingement over the entire 1974 outmigration 

### was about 12 times greater on 1/8- 

### than 

### on 1/4-in. screens. lhe Washington State Department of Fisheries estimates that the number of chinook outmigrants passing HGP in 1974was 5.56 milli~n.'~) Of this total, 1.61 million were 0-age chinook emerging from redds between the intake and Priest Rapids 

### Dam. The 

### total impingement 

### loss 

### tothis salmonid resource,as a result of the entire intake being 

### at 1/4- or 1/8-in. screens in 1974, would have been <O.l and 0.9%,respectively. Experimental releases of rainbow 

### trout in 1974 support the estimated impingement of naturully occurring chinook. Number and size of marked and unmarked rainbow trout impinged by 1/4- and 1/8-in. traveling screens are presented in Table 9. The half of the intake with 1/4-in. screens impinged 49 fish, representing 0.25%ofthe 20,000 unmarked fish released 500-601) yd

30ln P S N -7 m c9 m TJ m m c la h 22. 

## *

I N \ 

# -
S 0 P cu c, 

### P P 1 3 

### 9 ln 0 L m m 4J I- S W 3 h 3 c9 I 0­ 0 m m W n v) E: n -7 3 v) h I U m I c m a W

I I 

### 9 

### P v) c, =I h 0 m 0 c, -u .C

v) I c9 I m C W m m W L V a0 I h v) LL 0 0 N 

### s nL: 

# I zl w I h I N I- N N ce Oh W > cu. 0 w lu a, L tnE e- e- c, a0 l I I wlL m v) TI E m m .Ir W a w "9 W m m. Y IU c, E .C W in In' -0 .C S r VI w aJ C a, W -r we QI L L a0 u cu u V I m.- h 0.- in in C wo in u *r­ -m OL E ­ wv oww os W CLO w >Y L -r -0 2 I .C m
- 1 OLc, W u) o as E\ E w Lo 3 -C -7 u

I- Q 

# 4 4

7 c h 0 v)



## . 

# .. 7 c IZ

31

# . 1

upriver from the intake. Assuming equal numbers would be impinged ateach half

### of the intake ifscreens on both sides were of 1/4-in. openings, itis estimated that 0.5%would be impinged. Since 60%

### of the natural outmigrants move down the sides of the river(6) and conservatively assuming equal numbers 

### on each side (30%) these data indicatethat 0.15% of the outmigrants emerging from redds between HGP and Priest Rapids Dam would be impinged on the 1/4-in. screens. The half of the intakewith 1/8-in. screens impinged 280 fishor 1.4% of the 20,000 fish released. Using the same assumption (equal numbers impinged on each half), 2.8% of the released populationwould be impinged with the entire intake using screens of 1/8 in. Assuming equal numbers of outmigrants on each side of the river, 0.84% of the outmigrants emerging from redds between HGP and Priest Rapids Dam would be impinged on the 1/8-in. screens. Impingement was 5.7 times greater on 1/8-than on 1/4-in. screens for fish released upriver and 5.3 times greater for those released infront of the screens. The difference between these values and the 12-fold impingement increase on 1/8-in. screens for natural chinook populations may reflect a species difference. Young 0-age rainbow trout are deeper-bodied than naturallyoccurring 0-age chinook and impingement on 1/4- and 1/8-in. screens may not be the same for each species. The 1/4-in. screens impinged 2%of the fish released behind the curtain wall and infront of the traveling screens, while 13%were impinged on the 1/8-i1-1.screens. These values, however, do not simulate outmigration and therefore, they reflect only the relative difference inimpingement potential between 1-/4- and 1/8-in. screen openings for fish behind the curtain wall. Additionally, comparison of impingement for fish released behind the curtainwall with those released upriver indicate that impingement potential increases for fish once they are behind the curtain wall and infront of the traveling screens.. Impingement potential iseven greater for a fish immediately infront of 1/8-in. than it is infront of 1/4-in. openings.

32Passage Through 

### the Traveling Screens A large 

### number of 

### fish were observed inside 

### the intake 

### during the 1973 outmigration. 

### An estimate of the total number of fish 

### passing to the inside was not possible for 

### this period, alt-hough4,869 fish were collected inside 

### the intake from 29.March through 

### 23 July 1973 (Table 10). Many of the fish sampled 

### behind the screens were obviously too big (body depth 

### >0.9 

### cm) to have passed through the 1/4-in. screen openings 

### which are 0.64 cm 

### on a side. However, 

### a small fish

### with a body 

### depth (maximum distance between dorsal and ventral surfaces) greater than 

### 0.64 

### cm could potentially enter the intake by passing diagonally through 

### the screen

### mesh. The diagonal opening for the 1/4-in. screens is0.9 cm. The largest 

### fish sampled behind the screens was a sculpin (Cottus asper) which measured 2.9 (body depth) and 11.6 cm (fork length). These larger 

### fish could have either entered through the screens ata smaller size and resided in the intake for a period of time or entered recently around the screens. Data on residence 

### time obtained 

### in 1974 and identification of other possible avenues of entry (discussed below) 

### indicate that recent entry ismore likely.


### TABLE 10. Salmonids and Non-Salmonids Sampled Inside 

### the Intake Behind Screens from 

### 29 March Through 

### 23 July 1/4-in.

Total No. March 8 April 1436 hY 1851 June 84 July 15 1-20 July 23 1464 Total 4858 (a! F = Fintrol; DN

# - DiO kt Traveling 1393

Salmonids Mn-Salmonids Fork Length Fork Length Avg
. Total No. Avg. Range SarPD’2; 

### 0 

# B

- 0 MeTrvJ ’! 3.8 3.5-4.1 0 DN 3.9 3.2-4.9 8 3.5 3.1-4.1 ON 4.O 3.4-5.9 0 DN 4.7 3.3-7.1 0 DN 6.2 5.4-7.5 0 Dli
6.7 5.4-8.3 - 

## * 7.4 3.6-11.6 F.Dh 11

33

### --

-- -_ In 1973, 

### chinook salmon 

### (fork length range, 3.2-8.3 cm) made 

### up 

### the 

### entire salmonid catch (4858 

### fish) behind 

### the 1/4-in. traveling screens and 99.8% of 

### the total 

### fish catch (Table 10). In 1974, chinook salmon again made 

### up the 

### entire salmonid catch behind 1/4-in. screens (2451 

### fish, fork length range, 3.2-13.5 cm) and 

### 1/8-in. screens (1967 fish, fork length range, 3.4-12.7 cm). This species represented 98.9%(1/4-in. screens) and 99.2%(1/8-in. screens) of 

### the total 

### fish catch (Table 

### 11). Eleven 

### nonsalmonid individuals (fork length range, 3.1-11.6 

### cm) 

### were sampled behind 

### the 1/4-in. traveling screens in 1973 (Table 10); in 1974, 28 non-salmonid individuals (fork length range, 3.2-13.5 

### cm) were sampled behind 

### the 1/4-in. screens and 15 individuals (fork length range, 3.4-12.7 cm) were sampled behind the 

### 1/8-in. screens (Table 

### 11). The total number of.salmon collected
TABLE 

### 11. Salmonids and Non-Salmonids Sampled Behind 1/4- and 1/8-in. Traveling Screens from 

### 6 March Through 31 May 1974

1/4-in. Screens 1/8-in. ScreE Salmonids -.-___

~ Non-Salmonids Salmonids Non-Salmonids Fort Lenqth ___. (CT~ NO. (m) (cn\ Method NO. (cmi icm) NO. (cm) (cm) Method(d) Yar:b :' 4.; :.a-z.o 6 3.- 3.5-4.1 F,DN 35 4.1 3.7-4.1 5 8.3 4.0-12.7 F,DN A,-,..,: s?::b) 4.1 3.5-2.5 3 4.6 4.1-c.5 C.3N 456") 4.0 3.5-i.4 2 3.? 3.4-4.5 F,DN

?!5, I-> ;65 c.0 2.6-d ' D - 30 min Dip Net 79 3.9 3.5% 1 32 F,il. 3i; %! Fork Le3tL- Fort Length Fork Length Total Avg. Range Total Avq. Range Sample Total Avo. Range Total Avg. Range Sample NO. ICIP.)

u3 L 352 4.3 3.3-5.? 1 5.6 135 di?s 292 4 9 ?.3-5.G 1 3.9 - :?5 di:; q-:4
Yav !_3_L1 4.1 3.5-5.: ;6 L.: 3.2-12.5 F,DN

__ 1255 4.2 3.4-5.5 L 4.5 4.i-4.9 ;.?'.

- 15-31

. i = Firstro',:b = Dip x.7.

. , I. .-2P*> WE'+ e- ??-;- Lc-. . a:..' I*.)-. Sa->],"; (I$ An--:';

. .i,?. .r .,' :> 5­ in 1974was 

### not much greater behind 1/4-in. screens than behind 1/8-in. screens and estimates of total passage during the 1974 outmigration (discussed below) indicate that passage does notdiffer markedly witheither size screens.

34Rainbow'trout released insidethe intake and immediately recaptured by means of Fintrol and dipnet (i.e., no pumping) indicate the sampling method may be 60%efficient (Table 12). Other rainbow trout released inside the intakewere recaptured similarly after 16.5, 19.5, and 19.75 hr of pumping (Table 12). Extrapolation to the abscissa of the line (Figure 12) which shows the percent of fish remaining inthe intake atdifferent pumping periods, suggests that maximum residence time ofjuvenile rainbow trout insidethe intake is22 hr. Few fish (~1%) released inside the intake passed to the outside and subsequently became impinged (Table 9). Although this number was 6 times (12 versus 2 fish) higher with 1/4- than 1/8-in. openings, the number of individuals involvedwas too small toaffect estimates of passage losses. The data on residence time and direction of movement suggest that fish insidethe intake exit only through the plant condensers. Survival of condenser passage isnot possible due toa combination of thermal and mechanical stresses. Therefore, all fish passing behind the traveling screens are assumed to be destroyed.
TABLE 12. Numbers of Rainbow Trout Released and Recaptured Inside IntakeAfter Different Pumping Durations

llG. No. Percent of Corrected Percent o\f Pumping Time Intake Re1eased Recaptured Re1ease Re1

### easda, (Hr) ___- Side

__I~ 1000 599 60 100 

### 0 2 1500 259 17 28 16.5 1 1158 77 7 12 19.5 1 1150 

### 58 5 8 19.75 

### 2 (a) Correction based 

### on sample efficiency

35

# *I

I 0 5



### FIGURE 12. Percent After 

### D Passage Estimates RESIDENCETIMEONCE INSIDEINTAKE

o .ACTUALVALUES

VALUESCORRECTEDFOR SAMPLINGEFFICIENCY

0

I I I 10 15 20 HOURSOFPUMPING

of Released Fish in the Intake fferent Pumping Per ods

Estimates of passage behind 1/4- and 1/8-in. traveling screens can be made 

### from experimental releases 

### of rainbow 

### trout. Since 188 

### (or0.9%)of 20,000 fish released upriver 

### on the intake side were collected inhalf the intake behind the 1/4-in. traveling screens (Table 9) and with sampling efficiency estimated at 60%,approximately 313 (or 1.6%)of the released fish may pass behind the 1/4-in. screens. If the entire intake had been

36fittedwith 1/4-in. screens the estimate would increase to626 or 3.1% of the fish released on the intake side. However, 60%of the natural outmigrants move down both sides of $he river.(6) Assuming equal numbers on each side (30%),an estimated 0.9% of the natural outmigrants emerging from redds between HGP and Priest Rapids Dam would pass behind the 1/4-in. screens.. One hundred three or 0.5% of the released fish passed behind the 1/8-in. screens. Usi.ng the same assumptions and correcting for sample efficiency, 172 fish may have actually passed. Ifthe entire intake had been fittedwith 1/8-in. screens, about 344 (or 1.7%)of the released fish and 0.5% of the natural outmigrants emerging from redds between HGP and Priest Rapids Dam would pass behind the 1/8-in. screens. These data indicatethat changing the screens from 1/4- to 1/8-in. openings reduced total estimated passage from 3.1 to 1.7%of the 'released fish popu-lationand 0.9 to 0.5% ofthe natural populations emerging from redds between HGP and Priest Rapids Dam. For fish released behind the curtainwall and infront of the traveling screens, passage was 4.6 t.imes greater with 1/4- than 1/8-in. openings. However, these fish do not simulate natural outmigration but merely what happens once fish are behind the curtain wall. As with impingement, the potential for passage increases once rainbow trout get behind the curtainwall and the relative differences between the two screen sizes becomes greater. To place these data in perspective, consider that the released fish (rainbow trout) are deeper bodied than naturally occurring 0-age chinook and may not pass the screens to the same extent. Chinook of the same body length are more likely than rainbow trout to pass through an opening of a given size. Since rainbow trout inside the intake apparently exit through the plant condensers in

### less than 24 hr (Table 12 and Figure 12), each of the samples listed inTable 13 for March, April, and May 1974 may represent 24-hr chinook samples. When the values for these months are considered by day and corrected for sample efficiency, and assuming the entire intake isat either 1/4- or 1/8-in. openings, the estimated values can be plotted against time to show

37

### TABLE 13. Daily 

### Numbers of Chinook Salmon Sampled 

### on and 

### Behind 1/4- and 1/8-in. Traveling Screens by 

### Fintrol and Dip 

### Net During Spring 1974 1/4-i 

### n. 1/8-in.

-. Screen Impinged Screen Impinged March 27 

### 21 1 11 

### 4 28 15 2 

### (AM) ' 5 

### 34 (AM) 29 5 0 7 85 30 39 

### 0

. 12 3 No. Behind 

### No. No. Behind No

### -

total passage (Figure 13). The area under.the resulting curves for 1/4­ and 1/8-in. screens are estimates oftotal chinook passage 

### with the entire intake with 1/4- 

### or 1/8-in. screens 

### from March-June 1974. 

### An estimated 142,000 0-age chinook would have been passed with the entire intake at 1/4-in. and 120,000 fish if all the screens had been 1/8-in. (Table 14). This represents 8.8 and 7.5%of the 1974 estimated 1.61 million(9)chinook fry emerging from redds between the intake and 

### Priest Rapids Dam. These estimates based on numbers of chinook fry collected behind the screens are higher than the estimates based 

### on releases ofrainbow trout. The disparity

38

## -- -- ---lBlN.MESH

n 5112026 s11Zo; MARCH APRIL MAY 

### FIGURE 13. Estimates of O-Age Chinook Screen Passage for 1974


### TABLE 14. Summary of Estimated Impacts 

### Due 

### to Impingement and Passage of 

### O-Age Chinook Salmon with 

### 1/4-and 1/8-in. Screens During 1973 and 1974 Impingement Passage Tota1 Impact Impact Impact

­ % O-Age % O-Age % O-Age ChiPO:: !I( No.(a) Chinook(b) No. (' Chinook(b, No ___I_. __ 1973 1/4-in. Screens 600 

### - <1(e) 

## - ­ 1974 1/4-in. Screens 1,100 <1(dl <1(e) 141,800 1(dl 142,800 1(d) 9(e 1/8-in. Screens 14,100 1(dl 120,400 1(dl 134,500 1(d) 8(e

- (a) Based on estimates derived from screen wash samples, corrected for impinged fishcollected alive and rounded to the nearest hundred. (b) Fry emerging from redds between HGP and Priest Rapids Dam. (c) Based on estimatesderived from 24 hr intake samples and rounded to the nearest hundred. (d) Based on releases of rainbow trout. (e) Based on estimates of number impacted and Washington Department of Fisheries estimatesof 0.24 (1973) and 1.61 (1974) million chinook fry emerging .from redds between HGP and Priest Rapids Dam.



### 39may reflect species differences 

### inbody shape and behavior. Since much of the estimated impact 

### depends on residence time, and estimates from 

### data collected for rainbow 

### troutmay not be directly applicable to chinook, 

### it

### is possible that chinook residence time 

### inthe intake may be shorter than 

### 24 hr. Chinook losses in 

### this case would be higher than the above estimates.. 

### But, 

### the data 

### suggests that these may be worst case estimates, and that chinook residence inthe intake may be longer than 24 hr. Comparison of the daily numbers 

### of chinook sampled on and behind the traveling screens Table 

### 13) indicates 

### that the number of chinook seen behind the screens 

### on April 

### 18 and 23, and on May 

### 28 bears little, if any, relationship to the number of chinook impinged on the same dates (on other dates, however, the magnitude of passage is similar to impingement values). The magnitude of passage sample sizes on April 18 and 23 and May 28 suggest that these fish represent an accumulation of fish over 

### a longer period of time 

### than 24 

### hr; i.e. 

### ,residence time ofchinook in the intake may be longer than that for rainbow trout. Hence, passage rates for chinook extrapolated from trout data may overestimate chinook losses. 

### For example, if chinook resided 

### in the intake twice as long (i.e., 48 hr) as 

### trout, passage losses would be halved and total passage would represent 

### about 4.5%of the chinook population loriginating between HGP and Priest Rapids 

### Dam. To refine these values, itis essential to estimate chinook salmon residence time. Ongoing investigations are addressing this problem. During their first 3 weeks as fry, juvenile chinook salmon may pass the 118-in. openings. As the fry develop, however, 1/8-in. screen openings should prevent 0-age chinook passage. The appearance of fish behind the 1/8-in. traveling screens throughout the 1974 outmigration and the sizes offish sampled behind both size screen openings indicates that fish may be entering by some other means. There are several possible alternative routes for fry 

### tobypass the traveling screens and thereby enter the intake area other 

### than through the screen mesh. These are:

40t

0 Around the screens: engineer drawings of the intake show design openings of up to 5/16-in. along the sides and 1 1/8-in. at the ends where the "Z-frame" fits into the concrete side of the screen bay (Figure 14).(11)

0 Between the screen frames: the screen frames are not true, and openings between the frames vary greatly and inplaces are up to 3/8 in. wide (Figure 15). Under the screen: a design opening of at least 3/8 in. exists between the bottom of the screen and the bottom of the intake floor.



# -= 5/16 IN.-=

-_____ 14. FIGURE 

### INS1DE 

### INTAKE 

### INTAKE

### WALL

FRONT

### OFTRAVELING SCREEN



### 1518IN. CLEARANCE BETWEENPOSTANDWALL 

### SECTIONTHRU SCREENANDZ - 

### FRAME Schematic Through One Intake Wall Traveling Screen and "Z-Frame"

41

### The 

### least likely path of entry 

### is beneath the screen. Chinook fry are mainly surface oriented and the majority occur 

### inthe upper few meters of water

# .(6) About 30%of the fish collected at Beyers Landing, which 

### is shallower than infront of the HGP intake, were near the 

### bottom. SCUBA diver observations indicate 

### that there are deposits of siltand debris located along the entire outside length of the base of the traveling screens, which could serve to preclude passage under the screen. Additionally, attempts by SCUBA divers 

### to insert a thin 

### (1/8

### in.) metal 

### bar under the screens were unsuccessful, indicating that the possibility of passage of chinook fry under. the screens is unlikely. Wh-ile passage around the sides of the screen 

### is possible, a constant 5/16-,i.n. gap probably does 

### not exist along the sides 

### of the screens for the entire distance (60 

### ft)from top 

### to bottom. According to the screen manufacturer itis almost impossible 

### to pour concrete walls parallel for 60 ftthat provides a perfectly plum gap.(2) The most likely path of entry of small fish is through the gaps between the screen frames. These potential routes present considerable area 

### to the fry and are capable of passing fish. Closing the gaps between the screen frames can,beexpected 

### to lessen fish passage. However, itmay increase screen impingement.


### Total Impact 

### In assessing the potential impact 

### of the HGP intake with either 1/4- or 1/8-in. screen openings on O-age chinook from the Columbia River, 

### the total loss 

### of fish from screen impingement and passage must be determined. The total impact has 

### not changed if a reduction in screen passage is accompanied by 

### an increase in screen impingement of equal magnitude. Impingement 

### of chinook outmigrants has been estimated 

### tobe 12 times greater 

### on 1/8-in. than 

### on 1/4-in. screens. Total estimated passage of chinook outmigrants, however, is only 1.2 times greater on 1/4- than on 1/8-in. screens. The total number impinged is relatively low incomparison

43to the estimated total number of 

### fish passed and, therefore, 

### impingement makes a minor contribution 

### tothe total impact (Table 14). 

### The estimated impingement and passage losses (total impact) 

### with 1/4-in. screens in use across the entire intake during the 

### 1974chinook salmon outmigration are 

### 1100 impinged(a) and 141,800 fish passed 

### for a total impact of about 143,000 fish, or 

### 9%of the 0-age chinook emerging from redds inthe Columbia River between HGP and Priest Rapids Dam (Table 

### 14). The total impact with 1/8-in. screens equaled 14,100 (impingement 

### loss) plus 120,400 (passage 

### loss) or a loss 

### of 134,500 fish or 8%of the chinook emerging from redds between HGP and Priest Rapids Dam (Table 

### 14). While impingement was clearly greater on 1/8-in. screens, passage was 

### not changed from that which occurred with 

### 1/4-in. screens. Since impingement impacts are small in relation 

### topassage, the total estimated impact was virtually the same with both size screen openings. Chinook produced between HGP and Priest Rapids Dam represent about 

### 29% of

### a1

### 1 chinook outmigrants (natural 

### and spawning channel releases) passing the intake. Therefore, impingement and passages losses during any one year may represent 

### a maximum of3%ofthe outmigrants originating from upriver and passing HGP.

(a)Corrected for estimates 

### of the numbers of impinged fish which were collected alive.



### 44SUMMARY

### OF PRELIMINARYCONCLUSIONSSUMMARYOFPRELIMINARYCONCLUSIONS


### A study of screen impingement 

### and passage of fish 

### is being conducted by 

### BNW atHGP. The data from March 1973 through June 

### 1974 are reported here. 

### Based on these data preliminary conclusions of 

### this study are: Impact 

### is limited almost exclusively tojuvenile chinook salmon emerging from redds between HGP and Priest Rapids 

### Dam. Peak screen impingement and passage will occur inApril and May during the firstpart of the annual outmigration if the plant 

### is operated 

### at this time. Although the outmigration may continue through June, the fish are larger and are apparently not vulnerable to cooling water intake.
0 Use of 1/8-in. traveling screens resulted 

### inabout 

### 6 (experimentally released rainbow trout) and 

### 12times (naturally outmigrating juvenile chinook) greater impingement 

### than 1/4-in. screens. Impingement losses of 0-age chinook salmon vary as a function of intake screen size, intake velocity and source of fry. The estimated losses in 

### 1974 for fish emerging 

### .from redds between 

### HGP and Priest Rapids 

### Dam are <l%for 1/4-in. and 1%

### for 1/8-in. screens.
0 The impact of screen impingement was less 

### than screen passage. While 

### a few impinged fish may be washed off and survive, 100%of those passing the screens must be assumed 

### to be killed in passage through the plant condensers. Use of 1/4-in. traveling screens resulted in 

### 1.8 (experimentally released rainbow trout) and 1.2 times (naturally outmigrating juvenile chinook) greater passage than 1/8-in. screens.
0 The 1974 passage losses of0-age chinook salmon emerging from redds between HGP and Priest Rapids Dam were estimated to range from 1 (experimentally released rainbow trout) 

### to 9%(naturallyoutmigrat juvenile chinook based 

### on a residence time of 24 hr) for 1/4-in. and 1 (experimentally released rainbow trout)to 7%(naturallyoutmigrat juvenile chinook) for 1/8-in. screens.

450 The estimated combined impact of impingement and passage in1974 were about the same for 1/4- and 1/8-in. screens, and represented 1 (experimentally released rainbow trout) to 9%(naturally outmigrating juvenile chinook) of the chinook salmon emerging from redds between Priest Rapids Dam and the intake. These losses represent about 3%of the total estimated chinook outmigrants passing

### HGP.
0 Reducing the screen size from 1/4- to 1/8-in. has notgreatly reduced passage. Most of the fishapparently pass the screens inplaces other than through the mesh. Three possible pathways have been identified. These are openings or gaps thatoccur 1) inthe Z-frames, 2) atthe bottomof the traveling screens, and 3) between the screen frames. The latter seems the most likelypossibility. Closing these gaps should reduce passage through both size screens. This should make the 1/8-in. screens more effective inprecluding fishpassage than the 1/4-in. screens. Ongoing studies are addressing these questions.

46REFERENCESREFERENCES
1. Washington Public Power Supply System Corps of 

### Engineers Application No. 071-04B-2-000570, 13Apri

### 1 1972. 

### 2. R. H. Arrowood, 

### Mgr. Screening Equipment, Envirex, Inc., Personal 

### Communication. 3. 

### D. L. Park, Seasonal Changes inDownstream Migration of Age-Group 

### 0 Chinook Salmon 

### in

### the Upper Columbia River, 

### Trans. her. Fish. 

### SOC., 98(2):315-317, 1969. 4. C. 

### D. Becker, Temperature Timing and Seaward Migration ofJuvenile Chinook Salmon from 

### the Central Columbia River, USAEC 

### R&D Report, BNWL-1472, Battelle-Pacific Northwest Laboratories, Richland, 

### WA, 21 p., 1970. 

### 5. M. C. Bell, “Fisheries Handbook of Enqineerinq Requirements and Biological Criteria, Fish.

### -Eng

# . Res.lProg., torps of Engineers

### , North Pacific Div. 

### , Portland, OR, February 1973. 

### 6. 

### E. 11. Mains and 

### J. M. Smith, 

### The Distribution, Size, 

### Time, and Current Preferences of Seaward 

### Migrant Chinook Salmon inthe Columbia and Snake Rivers, Fish. Res. Papers, Wash. State Dept. Fish., 2:5-43, 1964. 7. Letter, Thor C. Tollefson, Director, Wash. Dept. 

### Fish. to M. J. Schneider, Battelle-Pacific Northwest Laboratories, 

### 12November 1973. 8. D. G. Watson, 

### “Fa11 Chinook Salmon Population Census,” In: 

### Ann. Rept. for 1972, Vol. 

### I, Part 2, Ecol. Sci., BNWL-1750. Battelle Pacific Northwest Laboratories, Richland, 

### WA, pp. 6.16, 1973. 9. R. Allen, Washington Dept. Fish., Wenatchee, WA, Personal Communication. IO. f.1. C. Bell, College of Fish., University ofWashington, Seattle, WA, 

### Persona

### 1 Communicat ion. 11. Rex Chainbelt Inc., Milwaukee, Wisconsin, Field Service Manual, Operation and Maintenance Instructions and Parts Catalog for Traveling Rater Screens 4 Post, The Hanford Electric Generating Project, Richland, W.4, Washington Pub1ic Power Supply System.

47

### APPENDIXA 

### CommonandScientificNamesof

### SalmonidsandNon-Salmonids--

-- APPENDIX A

Commonand ScientificNames

### of Salmonids and Non-Salmonids
SALMON1DS Oncorhynchus kisutch (Malbaum) 0. nerka (Walbaum)

- 0. tschawytscha (Malbaum) Prosopiumwill iamsoni (Girard) Salmo gairdneri Richardson
NON-SALMON

### IDS AciDenser transmontanus Richardson Acrocheilus alutaceus Agassiz & P Alosa sapidi-1 son) Catostomus macrochei1us Girard Cottus asper Richardson

- C. bairdi Girard

- C. beldi ngi Eigenrnann & Ei genmann

- C. perplexus Gilbert & Everrnann

- C. rhotheus (Smith) Cyprinus carpio Linnaeus Entosphenus tridentatus (Gairdner

-___ Gasterosteus aculeatus Linnaeus

-____ iepomis gi bbomaeus) Mylocheilus caurinus (Richardson) Perca f1avescmtchi 11) PercoDsis transrnontana Eiaenmann &

-

__I--- Richardsonius balteatus (Richardson Coho salmon Sockeye salmon Chinook salmon Mountainwhitefish Rainbow (steelhead) trout

White sturgeon .eri

### ng Chise1mouth American shad Largescale sucker Prickly sculpin Mottled sculpin Piute sculpin Reticu1ate scu1pi n Torrent sculpi n Carp Pacific Lamprey Threespine stickleback Pumpkinseed sunfish Peamouth chub Ye1low perch Eigenrnann Sand roller

1) Northern squawfish Longnose dace Leopard dace Redside shiner

A- 1