HABITAT IMPROVEMENT
PROJECT
Fishery Division
OREGON STATE GAME COMMISSION
P. 0. BOX 3503
PORTLAND, OREGON 97208
Lower Oyhwee River
Number 25
STATE OF OREGON
OREGON STATE GAME COMMISSION
FISHERY DIVISION
C. J. Campbell, Chief of Operations
LOWER OWYHEE RIVER
F-20-D-33
State-Wide Fishery Rehabilitation
By
Lawrence E. Bisbee
District Aquatic Biologist
Lower Owyhee River
Number 25
COMPLETION REPORT
STATE-WIDE FISHERY REHABILITATION
LOWER OWYHEE RIVER
F-20-D-33
Period Covered:
March 1966 to November 309 1967
ABSTRACT
In earlier years, the lower Owyhee River provided excellent trout
angling.
In recent years, the fishery had declined to one maintained with
the annual stocking of legal size hatchery trout on a put and take basis.
Stream surveys completed in 1966 indicated the 16 1/2-mile section
of the lower river lying between the Owyhee Reservoir dam and the old Owyhee
diversion dam in Malheur County, Oregon, would lend itself to periodic
rehabilitation and restocking annually with rainbow fingerling.
Chemical treatment of this section of river was completed on
March 18, 1967.
A large population of bridgelip and coarsescale suckers,
squawfish, chiselmouth, redside shiner, and carp were reduced.
A kill
estimated to be in excess of 63,000 fish resulted from the aerial application
of 225 gallons of liquid pronox-fish by helicopter.
Test fish confined in
live boxes along with net sampling indicated an incomplete kill.
Failure
of the chemical to penetrate the deeper water and rapid detoxification were
the primary causes for the incomplete kill.
Detoxification at the old
diversion dam was necessary to prevent destruction of walw-water game fish
below.
Rainbow fingerling totaling 97,642 were restocked in mid-April and
5,072 legal size rainbow were planted in late May 1967.
entering the catch in August.
Fingerling began
Angler success was excellent.
Location and Past History
The sixteen and one-half mile segment of the lower Owyhee River
chemically treated on March 18 lies approximately 20 miles southwest of the
communities of Nyssa and Adrian in Malheur County, Oregon.
The project began
at the base of Owyhee Reservoir dam (Photo No. 1) and extended downstream to
the old Owyhee diversion dam located in Section 18, Township 21 South,
Range 46 East. (See Photo No. 2)
Prior to the construction of the Owyhee dam in 1932, salmon and
steelhead were present in the river.
However, these species became extinct
in the upper Owyhee basin after the completion of the dam.
fishery existed in the lower river for some time.
A good trout
Lack of minimum flows
during winter months, heavy siltation, and pollution all contributed to the
elimination of the salmonid fishery.
In recent years, the only fishery pro-
vided by this segment of river was on legal size hatchery
trout stocked
annually in the upper five miles below the dam and a minor warm-water game
fishery.
Angler use on the stocked trout was moderately heavy while pressure
on the warm-water species was very light.
Good access to this segment of the river is provided by a surfaced road
paralleling the river. (See Photo No. 3)
No rehabilitation,work had been previously attempted on the river.
Management consisted solely of maintaining a trout fishery with an
annual stocking of 3,000 to 4,000 legal size hatchery reared rainbow trout,
periodic creel census to obtain catch data and occasional population sampling.
- 2 -
A physical and biological survey of the river was completed
in March 1966.
This section of river is composed of 80 large pools
connected by short riffles. (See Photo 3)
was 25 to 75 percent.
The ratio of riffle to pool
The pools average 294 yards by 18 yards by 1.7
feet in depth and contained a total volume of 265 acre-feet of water.
A summary of pool quality and dimensions is presented in Table 2.
A list of individual pools with average depths, estimated
surface area and volume is presented in Table 30
Fish collections taken prior to the treatment indicated
the presence of an abundant population of undesirable species of fish
(87.5%), a smaller population of warm-water game fish (11.5 %) and
very few trout (1.0%).
A summary of fish collections taken by gill net
net and rotenone prior to treatment is presented in Table 4.
trap-
Photo No.
1
The Owyhee Dam and the stilling basin; start
of the Owyhee River rehabilitation project.
Photo No. 2
The diversion dam located at the lower end of the Owyhee River
rehabilitation project.
_3
Photo No. 3
A section of the lower Owyhee River showing the long pools with a good
access road along the righthand side.
Preparation
The watershed for this section of stream is limited, consisting
of small tributaries or washes which flow water only during the spring runoff or when a heavy rain fall may cause a flash flood.
The main source of
flow originates from Owyhee Reservoir where irrigation water is released
April through early October, which in turn is diverted into the main diversion
canal at the diversion dam located 16 1/2 miles downstream.
A daily record of stream flow measurements for the period October
1964 to September 1965 taken at the USGS gage located one mile below the
Owyhee dam is presented in Table 1.
- 4
204
301
13.720
ONSE3iVEFi
Stream Flow Mesaurementa, U. S. Geological Survey
13-1830, Owyhee River below Owyhee Dam, Oregon
47,875.0
122.9
3.96
244
1,544
94,960
6.6130L
6.0
949
805
674
865
1,060
2,000
2,120
. 1,070
650
1,000
2,860
5,130
6.0
6.0
6.0
6.0
88
1,150
. 1,820
2,160
2,090
1,990
1,920
1,840
1,740
1,620
1,520
1,270
1,330
1,450
125,100
4,468
248,100
60,340
981
50,419.5
108
------
31,02:
1,001
61,530
1190
5,416
10,740
181
2,510
2,290
432
1,750
2,570
2,480
134
141
172
172
172
174
152
168
172
12622
.
.
166
542
750
565
265
118
144
168
2,120
2,200
2,150
2,070
2,000
1,390
324
May
BOO
114
114
114
264
111
112
105
106
108
.
. 106
108
120
128
122
101
102
117
126
126
126
102
108
111
2/
117
118
118
118
108
123
136
136
136
135
116
117
April
100
56
1,720
1,800
1,790
1,710
1,620
1,540
1,470
1,420
1,380
1,390
1.430
1,500
1,570
1,600
1,590
1,570
1,540
1,600
1,010
7.5
March
1221
3,190
3,200
2,630
2,170
2,030
1,900
1,800
1,840
1,880
1,930
* 1,890
1,830
1,810
7,600
8,720
8,250
7,600
7,530
7,810
7,740
7,690
7,510
6,980
5,940
4,590
3,900
3,440
Pabruary
2.5
3.0
Mean
Kean
.cre-feet
829,800
Acre-feet 1.619,000
Min
Min
12..2,000
73.1
720
Acre-feet
Acre -feet
55,100
521,500
_
Adjusted for diversions from ;Jake Owyhee. and change in lake cements
2,321
2,405
1,291
1,984
3,711
2,896
*
5.2
5.2
5.2
5.5
6.0
4.0
3.5
4.2
4.o
3.2
3.o
3.2
3.5
4.0
/.1.)
3.5
3.5
3.2
3.8
3.5
3.5
3.5
3.8
3.6
3.8
3.5
3.8
3.5
3.5
4.0
January
277
.)22.
9,560
'1,440
5e3
:5P
152
,,217.
.
4,721
186
liO
108
108
108
108
108
108
111
5,768
:?.tizi
214
206
190
* 214
146
147
147
146
156
*
148
140
142
147
156
170
145
120
120
172
166
162
186
117
124
128
128
200
208
200
196
190
184
172
164
176
180
1,1_,3E4
241
2,582
86.1
;,120
76
63
66
64
80
68
68
67
69
66
68
73
69
78
75
75
75
95
88
78
74
101
132
116
DI
September
Auguat
270
'6,070
250
214
226
150
148
174
202
228
218
208
224
212
208
208
214
228
228
206
192
180
174
162
172
180
. 180
180
180
182
170
164
150
July
8,102
*
176
178
156
134
134
1*0
_4-
202
222
222
222
224
224
224
210
196
186
885
209
180
IASI
June
Dischargs, in cubic feet Per second, water year October 1964 to September 1965
December
m Lischarge Measurement made en this day'.
1.4S6
ADJUSTED
Mean
1,45
Mar.
Max
225
107.2
3.57
215
3.5
5.5
3.5
3.5
3.5
3.5
3.5
3.8
3.5
3.5
3.5
* 5.5
..------
3.8
3.5
3.5
3.5
3.5
3.5
3.5
3.5
3.8
3.5
3.5
3.5
3.5
3.5
3.5
4.0
3.8
LSI
November
aster year 964-451 Mean
Calendar year 1964:
Calendar year 1964;
dater year t566-0.1
k==1W.12,5241
Mean
1,719.6
55.5
3,410
4.0
31
Total
Mean
Acre-feet
3.8
4.2
4.0
3.8
3.8
4.0
4.0
29
30
23
24
25
26
27
28
5.2
3.5
3.5
3.5
3.8
.2.,2
18
19
20
21
22
3.5
76
98
97
100
100
86
86
88
100
102
111
130
/M
120
118
122
October
17
16
14
15
13
12
11
10
9
8
7
5
6
2
3
4
1
Day
Table
OWYHEE RIVER b&OIN
16.50
MP 12,25
through
MP 28.75
5
5
3
8 to 10
lo to 15
15 to 20
80
1
8
6 to 8
20 to 40
23
6
22
4
4 to 6
2 to 4
0 to 2
3
of
Pools
Depth
(feet)
Number
Pool zi
Figured on maximum depth
Total
Miles
Surveyed
Stream
and
Section
Good
Good
Good
Good
Good
Good
Good
Fair
Poor
Fair
Pool
Quality
35000
560.0
1100.0
1200.0
1300.0
7500
460.0
170.0
30.0
225.0
265.0
110.0
80.0
50,0
20,0
12.0
55.0
20.0
70.0
294.0
11922.
432 0
558.0
44000
603,0
318;3
161.5
90,8
25.0
133.8
Pool length(yards)
Max.
Min.
Ave.
6o.o
30.0
30.0
35.0
40.0
35,0
25.0
20.0
8.0
20.0
14.0
20.0
12,0
7.0
5.0
8.0
6.0
4.0
12.0
18.0
60.0
23.0
26.0
22.4
23.0
18.2
13.5
10.0
6.7
14.8
Pool width(yards)
Max.
Min.
Ave.
A summary of pool quality and dimension data for the lower
Owyhee River M.P. 12.25 through M.P. 28.75 - March, 1966
Table 2
263,7
1.7
5.7
38.0
3600©
43.3
30.0
70.4
48.9
11.0
105
0.3
0.6
18.9
303
2.6
2.1
1.4
0.62
0.9
0.2
0.45
3.2
16.5
13,1
9.3
7.3
4.7
2,5
3,1
1,2
1.5
Ave. Max.
Total
Ave.
Depth
AcreDepth
Feet
(feet)
(feet)
Table 3
Pool data for the lower Owyhee River from Owhyee
Dam down to the old diversion, M.P. 28,75 down to 12.25
Stream
Section
Milepost
Pool
Number
Owyhee Dam
MP 28.75
1
2
3
4
Culverts
110 yards
above
MP 27.75
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
MP 24.25
Stone Corral
MP 23,50
Tunnel
23
24
25
26
27
Average/1
Depth 4-(feet)
Surface
Area
Maximum
Depth
(acres)
(feet)
Volume
Acre-feet
19,0
1.7
1,3
1,2
2,0
104
0.9
2,5
36.0
7.0
5.0
5,0
38.0
2.4
1.2
3.0
0.3
0.3
0.5
0.9
0.3
0.3
1,5
0,09
0,7
1.4
0,3
2.9
2.0
2,0
3.0
4,0
3.0
10.0
4.0
2.0
800
700
3,0
5.0
5.0
4,0
5.0
1,5
3.0
6.0
101
0.7
2,8
0.9
0,4
1.3
1.9
0.8
1.3
0.5
3.9
0,7
4,9
0,2
1.1
2,1
0.9
0.2
0.6
1.4
0.7
0,03
0.06
0,9
0.7
0.2
0,5
0,04
1.8
1.6
0,06
0.3
1.5
28
4.2
1.3
0.7
29
30
0.4
0.4
31
1.1
32
1.6
0.5
0.6
0.30.8
0.8
0,9
0.6
1,0
2.0
33
34
35
36
37
38
39
40
41
0.3
0.4
2.2
3.9
0,1
0.4
0.02
0.5
005
0.5
001
0.5
2.4
7
0,3
0,09
0,2
1.7
0,06
2,0
1,3
0,12
3,8
704
0,6
6.4
001
2.3
0.6
0.06
0,04
1,3
18,0
5.0
4.0
1,3
0,08
2,7
607
0.08
0,2
2.0
4.0
9.0
8.0
3,0
3.0
2,0
3.0
4.0
6.o
3.0
5.0
11.0
0008
0,2
2,4
6.2
0.5
0.2
0.006
0,4
0.4
0.5
0.07
005
4,8
4.0
1.5
7.0
Table 3 (continued)
Stream
Section
Milepost
Pool
Depth L---
Surface
1
Area
Number
(feet)
(acres
MP 21.00
42
2,3
1.4-
16.0
3.2
2.9
1,9
2.9
1.2
1,2
1.7
4.6
2.8
0,09
8,1
0.60.5
1.5
0.5
9.0
4.0
8.0
3,0
3.0
6.o
15.0
3.0
1.8
2.6
0.6
2.6
1.9
0.4
1,9
0.7
0.5
0.07
3,5
10.0
6.0
6.0
3.0
7.0
5.o
3.4
1.8
0,3
0,18
6.7
0.5
2.2
1.4
1.5
0.6
0.01
0,08
3.0
10.0
4.0
5.0
3.0
0,005
004
0.3
2,9
0.05
1.6
1.8
1,5
1.0
0.05
1.9
0.08
0.7
2.9
5.0
6.0
5.o
5.0
8.0
17.o
1.6
0.07
0.09
0.3
71
0.9
1.4
1.3
4.3
1.6
1.2
1.4
3.0
4.0
3.0
15.0
5.0
72
2.1
8.7
10.0
18.3
73
74
0.6
2.8
0.1
4.8
4.0
13.0
13.4
75
76
1.5
2.6
0.2
6.8
5.0
14.0
0.2
17.7
Averag91
Tunnel Canyon
80 yards above
MP 20.25
43
44
45
46
47
48
49
MP 18.50
Steel bridge 50
51
52
53
54
55
MP 17.25
56
57
58
59
60
MP 16.50
61
62
63
64
65
66
MP 15.50
Hot Springs
MP 15.00
MP 14.25
Siphon
MP 13.75
67
68
69
70
0.9
2.2
3.1
10 ©6
0,2
0.2
1.9
- 8 -
Maximum
Depth
(feet)
Volume
Acre-feet
0.17
30.7
0.7
006
2.6
2.3
1.2
0.09
2.9
0.07
1.5
9.0
0.6
0.13
0.4
5.1
2.2
0.06
Table 3 (continued)
Stream
Section
Milepost
Average
Surface
Pool
Depth Ll
Area Z1
Maximum
Depth
Number
(feet)
(acres)
(feet)
Volume
Acre-feet
77
78
79
0.7
0.6
0.7
0.06
0.06
0.05
3.0
3.0
4.0
0.04
0.04
0.04
Old Diversion
Dam
80
3.0
8.1
8.0
MP 13.00
24.3
At time of survey in March 1966, there was an estimated 90 cfs flow in the
river. At the time of treatment, the flow was down to 4.0 cfs at the dam
and 8.0 cfs at the lower end of the project. Pool depths were estimated
to be 0.5 feet lower at the time of treatment.
After preliminary stream surveys were completed, it was determined
that this section of the lower Owyhee River could be developed into an excellent
trout fishery similar to that on the lower Malheur River.
The isolation of
this section from the rest of the river by the Owyhee dam on the upper end
and the diversion dam on the lower end would assist in prolonging the
reinfestation of rough fish.
avenues.
Reinfestation could occur by three separate
First, if and when the reservoir filled and overflowed, some waLw-
water game fish and rough fish would survive the 300-foot plunge down the
overflow tube.
The reservoir has spilled about once every five years.
The
second avenue, and most probable source of reinfestation would be the main
canal and its three siphons which are drained into the river each fall at
the close of the irrigation season.
Every year varying numbers of fish are
found in the canal when it is shut down.
Partial treatment of the canal and
the three siphons just prior to the time they were drained would eliminate
most of the fish present.
It would be difficult to get all the fish in the
long tunnel leading back to the reservoir.
Any fish remaining alive could
find their way into the river down Tunnel Canyon.
-9
9.6
9.8
17.6
10.5
37.8
58
62
104
224
TOTAL
PERCENT OF TOTAL
57
44
_i
____i_
_i_
Gill net
October 11, 1965
1
6
M.P. 27.25
4
39
14
135
Gill net
October 12, 1965
18
M.P. 23.75
2
3
Rotenone
4
31
October 3, 1966
7
13
73
52
September 23, 1966 Trap net
M.P. 20.25
1
Redside
shiner
M.P. 23.00
3
4
9
30
Gill net
October 12, 1965
M.P. 18.50
Black
crappie
Method
Squawfish
Date
Bridgelip
sucker
Station
Location
Chiselmouth
9.1
54
1
25
24
4
Coarsescale
sucker
A summary of fish collections taken in the lower
Owyhee River between M.P. 12.25 and M.P. 28.75
prior to treatment, October 1965 - October 1966
Table 4
2.7
16
13
3
Dace
1.2
7
7
Bluegill
sunfish
1.0
6
3
2
0.5
3
2
1
Channel
Rainbow catfish
0.2
1
1
Carp
The third avenue of reinfestation could be by way of the diversion
canal at the lower end of the section.
Some fish and especially carp survived
in the deeperpotholes throughout the winter and could work their way back up
However, it would be possible to treat a good
the canal and into the river.
share of this canal and temporarily eliminate any fish that might be present.
Another possible source of reinfestation at this point would occur any time
the Owyhee dam overflowed.
Excess water would spill over the old diversion
dam making it possible for fish to pass on upstream.
However, in normal
years, the dam can be made into a total barrier.
The early spring of the year just prior to the release of irrigation
water was chosen as the time for treatment for several reasons.
By late
September when treatment work is generally done, the Owyhee River is choked
with thick mats of green algae.
The algae would not only consume the
In
rotenone rapidly, but it would also prevent penetration in many areas.
early spring, the algae is not present in such abundance.
be at a minimum prior to start of the irrigation season.
Stream flows would
The chemical could
be applied to the pool areas and then flushed out as the release of irrigation
water began for the season.
Restocking could occur shortly afterward.
Coordination with local groups was not a major factor, since public
use of the area was almost nonexistent except for a short period in the spring
following the stocking of legal trout.
Public opinion favored the project.
Some coordination was necessary with the North Board of Control (Owyhee
Irrigation District) in timing the project just prior to the release of
irrigation water.
It was necessary to secure the cooperation of the Oregon Ditch
Company that controlled the operation of the old diversion dam and of the
private landowners along the river.
® 11
Preparation for the project followed the general pattern of
activities prior to any treatment.
Live boxes of test fish were placed at
various points throughout the section.
at the starting point.
Rotenone and equipment were assembled
Drip stations were installed on the tributaries.
News releases explaining the project were placed in the local newspapers and
Arrangements were made with an aviation company
on the local radio station.
for the use of a helicopter.
up.
Necessary personnel for the project were lined
Detoxification equipment was set up on the canal below the diversion dam.
A chemical analysis of the water was taken prior to treatment.
Results of the analysis is presented in Table 5.
Table 5
A summary of chemical analysis of water
samples taken in the lower Owyhee River
between the diversion dam and Owyhee Reservoir Dam
Station No.
Station No.
Station
Number
1
2
Location:
Location:
Date
pH,
M. P. 13.75, road crossing below siphon
USGS gage station, one mile below Owyhee
Dam at M. P. 27.75
Conductivity
Micromhos
Alkalinity
Total dissolved
Carbonate Bicarbonate per cm
Solids (ppm)
1
June 2, 1965
7.91
145
0
72.8
195
2
June 2, 1965
7.96
175
0
7408
190
August 16, 1965 7.95
184
0
90.0
240
A series of water temperatures were taken with a maximum-minimum
thermometer at M.P. 14025 to determine the suitability of the lower stretch
of river for trout populations.
The data is presented in Table 60
- 12 -
Installed
Averages
,31
29
30
27
28
23
24
25
26
22
21
20
19
17
18
13
14
15
16
12
11
10
8
9
7
6
5
4
3
2
1
June
Min.
Max.
Day
63 ©5
54
54
54
62
65
Min.
MAX,,
July
56
55
66
54
56
54
Min,
67
62
67
Max.
68
August
63
65
61
54.4
57
52
September
Max.
Min.
62
61
Max.
63
47.5
51
44
October
Min.
Removed
Max.
Min,
WATER TEMPERATURES IN DEGREES FAHRENHEIT
Maximum-minimum
Location 1/4 mile above the
thermometer
Stream or Impoundment Owyhee River
Type of Instrument
siphon on north bank - MP 14.25
Dates Covered June 29, 1965 through October 14, 1965
Table 6
Water temperatures taken with a pocket thermometer just prior to
the treatment at 8:00 a.m. were 46 degrees F., one-half mile below Owyhee
Dam and 56 degrees F., at the detoxification station below the diversion
dam.
Chemical Treatment
Side Tributaries
1. Equipment and supplies used:
2.
a.
Three 30-gallon drip barrels with constant flow dispensers.
b.
Three barrel racks.
C.
One backpack can
d.
One 5-gallon bucket
Personnel Needed:
Two men
3.
Man-days required:
4.
Chemical:
two
Pro-noxfish
5 gallons for drippers
1 gallon for backpack cans
5.
Tributaries Treated:
Stream
Miles Treated
Tunnel Canyon Creek
1.0
0.3 cfs
Snively Gulch
0.5
0.2 cfs
100 yards
0.5 cfs
Snively Spring
6.
Flow
Drip stations were turned on at the time the treatment started
and were operated for eight-hour period.
A spring seep area
above the drip station on Snively Gulch was treated with a backpack can.
- 14 -
Main Stem
1.
2.
Equipment Used:
a.
One 4-man rubber boat with oars
b.
One 14 foot aluminum boat
c.
One 18 HP outboard motor with gas
d.
Ten live boxes with floats and ropes
e.
One venturi attachment with hose and barrel fittings,
f.
One 30-gallon drum
g.
One rotenone pump
h.
One barrel bung opener
i.
Four backpack cans
j.
One 30-foot seine
k.
Two 5-gallon buckets
1.
One trailer house
m.
Two detoxification units with electric pumps attachments.
Personnel Needed:
Photographer - 1 man
Rotenone supply - 2 men
Helicopter pilot and mechanic - 2 men
Coordination - 2 men
Detoxification station - 1 man
3.
Man-days required:
a.
Preliminary - 7
b.
Treatment - 7
c.
Detoxification - 6
d.
Post treatment - 2
- 15 -
4,
Chemical Used:
Pro-noxfish - 225 gallons
0 2.0 ppm
Potassium permanganate - 350 pounds
5,
Miles Treated:
16 1/2 miles
The chemical treatment of the main stem of the river began on
the afternoon of March 17, 1967.
The stilling basin below the dam
(see Photo No, 1) was treated with 30 gallons of pro-noxfish toxicant
applied by boat and outboard motor equiped with a venturi attachment.
Chemical treatment of the remainder of the river began at 8:30 a.m.
on March 18, 1967, one-quarter mile below the Owyhee Dam and progressed
downstream to the diversion dam®
Application of the chemical was made by
a helicopter leased from Helicopters, Inc., Boise, Idaho.
For proper
application it was necessary for the helicopter to fly not more than three
or four feet above the surface of the water. (see Photo No, 4)
A drip station was placed at the culverts just below the Reclamation
headquarters to introduce rotenone into an area where power lines and trees
prevented the helicopter from obtaining adequate coverage.
A pickup loaded with rotenone followed the progress of the helicopter
downstream.
Numerous open level areas provided landing strips for the machine
when it was necessary to refuel and replenish the supply of chemical.
(see Photo No, 5)
Application time required approximately three hours; however,
were several lengthy delays required to modify the equipment.
- 16-
there
Photo No. 4
Helicopter applying rotenone to a long pool
on the lower Owyhee River, March 18, 1967
Photo No. 5
Game Commission crew replenishing the supply
of rotenone in the helicopter tanks.
-17-
Detoxification began at the lower end of the project area at
2:00 p.m. when test fish indicated that rotenone was beginning to pass
through the station. (see Photo No© 6)
The station was operated on a 24-hour basis®
Detoxification
was discontinued at noon, March 22, when test fish no longer indicated
distress.
Areas which were either missed or were located where the helicopter could not adequately cover them were treated by hand with backpack
cans. (see Photo No. 7)
Some problems were encountered during the operation.
Weather
conditions were not the best for flying on such a hazardous job.
A
blustery wind made flying in and around power lines, trees, and the narrow
canyon difficult.
An accurate rate of application to maintain a continuous
concentration of 2.0 ppm throughout the entire river section required
constant surveillance.
There was considerable public interest in the treatment project.
A large crowd estimated at several thousand people turned out to view the
operation and salvage fish. (see Photo No, 8)
Results of the Treatment
In the stilling basin below the dam, rainbow trout and redside
shiners began surfacing within 30 minutes after treatment began.
and carp took somewhat longer to appear.
Suckers
In the remainder of the river
distressed fish did not begin to show for an hour or more.
However, by
mid-afternoon many carp, suckers, chiselmouth and squawfish were in distress.
(see Photos No. 9 and 10)
- 18 -
Photo No. 6
The detoxification station located on the
canal below the old diversion dam.
Photo No. 7
Treating areas by hand which could not be
reached with the helicopter.
- 19 -
Photo No. 8
Sportsmen waiting to salvage game fish.
Photo No. 9
View of the shoreline after rough fish began surfacing.
- 20-
Photo No. 10
Species and average size of fish killed in the
lower Owyhee River.
Distressed fish were still abundant on March 21.
Some live carp
and suckers were found in the vicinity of the tunnel and Tunnel Canyon as
late as March 27.
A number of live carp were observed in the Hot Spring
below the siphon in April, long after the river had been flushed out by
irrigation water.
Strip counts along the various sections of the shoreline were
made in an effort to estimate the total kill.
removed.
About 63,000 adult fish were
Many small redside shiners and dace were not counted since they
deteriorate rapidly or settled to the bottom of the pools and were no longer
visible.
Unknown numbers of large fish were also lying on the bottoms of the
deeper pools and could not be included in the estimate.
Results of shoreline
strip counts used to determine the kill is presented in Table 7.
- 21 -
50,990
Many small fish lying in deep pools not included in the estimate.
TOTALS
11,950
306
561
0.1
Rainbow
11
51
501
2,499
151
Li
5.8
0.1
0.5
1.2
1,3
1,3
Yellow perch
Dace
693
11
Channel catfish
Unidentified
60
Cottid
143
Black crappie
155
155
Li
Black bullhead
Bedside shiner
1.1
0.3
0.6
0.1
1.0
4.9
62,940
561
151
317
693
100.0
0.9
0.2
0.5
1.1
0.1
0.1
6o
62
1.0
0.3
4.2
0.5
653
155
2,654
293
0.2
102
1.6
191
Largemouth bass
0.6
35o
0.1
51
2.5
299
Bluegill
3.3
2,107
50.0
27.6
3.1
1,581
4.4
Sqauwfish
31,487
17,381
9.6
9.9
55.3
23.4
Total Kill,
Estimated
Percent
of
Kill
6,016
526
5,048
8.1
LI
28,198
27.5
11,932
968
3,289
Bridgelip sucker
and
Coarsescale sucker
45.6
SECTION 2
M.P. 18.50 to M.P. 28.75
Number
Percent
Chiselmouth Li
5,449
Carp
Species
SECTION 1
M.P. 12.25 to M.P. 18.50
Percent
Number
Species and estimated numbers of fish killed, determined by
shoreline strip counts on the lower Owyhee River, March 18, 1967
Table 7
The Diversion Canal and Siphons
On October 13, 1967, at the end of the regular irrigation season,
the main diversion canal was shut down.
When the flow had dropped to an
estimated 30 cfs, a drip station was turned on at the outlet of the tunnel
at Tunnel Canyon and rotenone was carried down the canal and through the
three siphons.
Water from the siphons would later be emptied into the
section of river previously treated on March 18, 1967.
By evening the flow in the canal had diminished to a trickle.
Any fish remaining in the tunnel above the drip station could conceivably
work their way out and down Tunnel Canyon and into the river.
Treatment
of the tunnel is impossible.
An estimate of the fish killed in the canal and the siphons was:
Species
Size Range(inches)
Black crappie
1
to 3
5 to 7
160
Yellow perch
4 to 7
250
Rainbow
9 to 15
13
Bridgelip sucker
9 to 11
4
Chiselmouth
7 to 8
3
Black bullhead
6 to 9
3
Carp
13
1
Number
35
Testing for Completeness of Kill
Eight live boxes containing species of rough fish and warmwater
game fish were placed at various stations.throughout the section to determine
the effectiveness of the treatment.
A number of live boxes were placed in
the deeper pools to check the penetration.
-23-
In Live Box No. 1, placed at a 36-foot depth in the stilling basin
below the dam, carp and bass did not show any distress until the fifth day.
All were dead by the sixth
day after treatment, Live Box No. 2 was stolen.
In Live Boxes No, 3 and 4, placed at depths of 13 to 19 feet,
12-inch carp survived.
Live but distressed suckers and carp were still
observed swimming on the surface in the vicinity of Stations No. 3 and 4 on
March 27.
Test fish in live boxes at Stations No. 5 and 6, placed at depths
of two to eight feet were dead on the second day after treatment.
A series of water temperatures were taken at Stations No. 1, 3,
and 4 on March 24, 1967.
Temperature data is presented in Table 8.
As a further check for the completeness of kill, five over-night
gill net sets were made on March 28, 1967.
stations except No
1 below the dam.
Live fish were taken at all
Results of the net sets is presented
in Table 90
Testing for Toxicity
Largemouth bass and bluegill fingerling were used to test for
toxicity after treatment®
In one live-box placed at a depth of four feet
in the large pool just below Tunnel Canyon on March 21, bass and bluegill
fingerling survived seven hours before expiring.
A live-box containing
bass and bluegill placed just above the detoxification station on March 20
still contained live fish on March 22®
A live-box was placed in shallow
water one-half mile above the detoxification station on March 21,
The
fish were dead after one and one-half hours of exposure. Additional bass
and bluegill placed in the same livebox on March 22 were still alive after
6 1/2 hours but were showing some distress.
-24-
On March 24 they were dead.
Table 8
Water temperature taken at three stations
March 24, 1967, six days after chemical treatment
Station No.
Location
0
Depth
Temperature
1
hee Dam
mile above Tunnel Can on
Temperature
Temperature
(°F.)
(°F.)
(feet)
Surface
4
3
Tunnel
43
49
48
1
43
49
47.5
2
43
47.5
47.5
3
43
47.5
46.5
4
43
46.5
46
5
43
46
45
6
43
46
44
7
43
46
44
8
43
45.5
44
9
43
45.5
44
10
43.5
11
43
45
43.5
12
43
45
43.5
13
43
45
43
14
43
44.5
43
15
43
44.5
43
16
43
43.5
43
17
43
43.5
18
43
43.5
30
42.5
36
42
-25-
Table 9
Results of five gill nets fished overnight
in the lower Owyhee River, March 28, 1967
Percent
of Total
1-1-
Number
Taken
Coarsescale sucker
31
11 to 19
53.4
Chiselmouth
14
6 to 10
24.1
Bridgelip sucker
10
8 to 14
17.3
Species
Size Range
(inches)
Squawfish
2
8 to
Black bullhead
1
9
9
3.5
1.7
LI Live carp were observed swimming around; however, none were taken
in the net samples.
No further tests for toxicity were made since the release of
irrigation water began on April 3 and any toxic water remaining was
flushed out.
Restocking
Restocking of the river with fingerling and legal size rainbow
trout commenced on April 11, 1967.
Fingerling rainbow were distributed
throughout the upper 13 miles of the rehabilitated area.
Legal trout
were released in the upper five miles below the dam.
A record of the trout stocked in the lower Owyhee River in
1967 is presented in Table 10.
The rainbow fingerling began entering the angler catch in early
August.
By mid-August these fish averaged approximately eight inches in
length.
The legal trout released at 8 inches were now averaging 12 inches.
-26-
Table 10
Rainbow trout stocked after chemical treatment;
lower Owyhee River, 1967
Date
Number
Released
April 11, 1967
58,514
864
69.6
3.3
April 12, 1967
10,163
179.5
56.6
3.5
April 13, 1967
5,072
1,059
28,965
599
5,072
1,059
May 27, 1967
TOTAL -
Legal
Fingerling
97,642
Pounds
Released
Number
per pound
4.79
48.4
Average Size
(inches)
8.0
3.75
1,642.5
Creel Census
Anglers began fishing the rehabilitated section by early August
in small numbers.
Little angling occurred on the legal size trout planted
early in the spring.
By October, anglers were using the upper five miles
of the area in fair numbers.
Of the anglers checked, 29 percent origin-
ated from the State of Idaho.
Angler success was excellent.(see Photos
No. 11 and 12)
atremely mossy conditions in the river hindered angling
and many would-be fishermen were discouraged.
A summary of creel census data for 1967 is presented in Table 11,
-27-
Population samples were taken in the rehabilitated section
on October 24, 1967, with three gill nets and one trapnet set overnight.
A large number of rough fish were taken. Many )f these were fish of the
year.
Few trout were taken; however, this does not correlate with the
excellent angling success experienced by those fishermen utilizing the
riffle areas.
Many large crayfish were also taken in the net sample.
The fall population inventory results for the lower Owyhee
River rehabilitated section are presented in Table 12.
293
211
30
2
16-18
598
Total
Fish
146
Total
Anglers
276
Total
Hours
4.1
Fish per
Angler
2.1
255
2
2
151
19
14
259
245
31.9
22.3
20.2
12.8
7.5
3.2
5
Ito 11
(inches)
2 to 17
1
to 15
1
to 4
1
to 6
1
to 4
0.3
37.4
35.4
2.8
2.0
21.8
0.3
of Total
Size Range
rrariet.2-LL--f-
Number
of Total
283
2
2
5
0.6
0.3
0.3
20.1
158
26
38
36.8
33.8
4.8
3.3
N.)
Percent
of
Total
289
266
Total
2.17
Fish per
Hour
Table 12
A Summary of the Catch Taken by Trapnet and Gill net in the Rehabilitated Section,
Lower Owyhee River, October 24, 1967
62
Gill Net
Number
Size Range
Species
(inches)
Coarsescale sucker 30 11 to 18
21
10 to 16
Bridgelip sucker
Chiselmouth
7 to lo
19
12
6
to 13
Squawfish
5
to 7
7
Carp
Black bullhead
9
to 10
3
2
Rainbow
9
Yellow Perch
28
Crayfish
Rainbow
Species
Size Groups (inches)
10-12
6-8
8-10
12-14
Table 11
A Summary of Creel Data for the Rehabilitated Section,
Lower Owyhee River, 1967
Photo No. 12
Rainbow trout taken by anglers in November in the lower Owyhee River after chemical treatment and
restocking with trout. All but one fish shown are from the April fingerling plants.
Photo No. 11
0