FEDERAL WATER QUALITY ADMINISTRATION
NORTHWEST REGIONAL OFFICE
October • 1970
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An Evaluation of Salmonid Hatchery Wastes
Prepared by
Danforth G. Bodien
Technical Assistance and Investigations
U.S. Department of the Interior
Federal Mater Quality Administration
Northwest Region
Portland, Oregon
October, 1970
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TABLE OF CONTENTS
Page No.
"INTRODUCTION 1
Problem 1
Authority 2
Scope 2
Objectives 2
Acknowledgements 4
SUMMARY 5
Findings and Conclusions 5
Recommendations 6
HATCHERIES .SURVEYED. . .- 7
Salmon Cultural Laboratory 7
Eagle Creek National Fish Hatchery 8
Little White Salmon National Fish Hatchery 9
Dworshak National Fish Hatchery 10
SAMPLING PROGRAM AND ANALYTICAL METHODS 13
WASTE CHARACTERISTICS 17
Physical-Chemical Characteristics 17
Total Waste Load 29
EFFECTS ON WATER QUALITY 31
Physical-Chemical Effects 31
Biological Effects 33
TREATMENT METHODS AND NEEDS 39
Water Reconditioning/Reuse System 39
Other Treatment Methods 44
Design Criteria 45
DEFINITION OF TERMS 49
BIBLIOGRAPHY 51
APPENDIX 53
Letter of Request 55
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LIST OF FIGURES
Figure Page No.
1 Location of Salmonid Hatcheries in the Pacific
Northwest Indicating Those Surveyed 3
2 Diurnal Temperature Curves for Five Stations at the
Eagle Creek Hatchery 19
3 Diurnal Dissolved Oxygen Curves for Five Stations at
the "Eagle "Creek Hatchery 20
4 Diurnal Dissolved Oxygen Curves for Upper Pond
Influent and Effluent at the Eagle Creek Hatchery. . . 21
5 Diurnal Total Coliform Counts for Five Stations at
the Eagle Creek Hatchery. 24
6 Filter Backwash Mater BOD Curves 27
7 Schematic Drawing of a Typical Controlled Environment
System for Rearing Salmonids (4) . .- 41
8 Design Drawing of a Water Reclamation Filger (4) ... 42
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LIST OF TABLES
Table Page No.
1 Hatchery Sampling Sites 14
2 Waste Loading Factors of Hatcheries Surveyed with
Reconditioning/Reuse 22
3 Waste Characteristics of Oyster Shell Filter Backwash
Water. . 26
4 Removal Efficiencies of Settling for Backwash Water. . 28
5 Hatchery Discharge- Effects on Water Quality of
Eagle Creek 32
6 Hatchery Discharge Effects on Water Quality of
Abernathy Creek 34
7 Eagle Creek Biological Data 35
8 Oyster Shell Filter Waste Treatment. 43
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INTRODUCTION
Problem
Throughout the Northwest Region 114 State and Federal hatcheries
produce an estimated 8.6 million pounds of salmonid fish annually.
In addition, the Region contains numerous private hatcheries and fish
farms. In the Hagerman Valley alone such hatcheries produce over 4.5
million pounds annually with a developmental potential of 20 million
pounds. Large quantities of water are utilized in raising fish,
and generally the water used is discharged without treatment to the
receiving stream. In most cases no problems have been associated
with this method of operation. Within the past few years, during low
summer flows, however, wastes discharged from some hatcheries have
created nuisance conditions in receiving waters. These conditions
prompted the Bureau of Commercial Fisheries (BCF) and the Bureau of
Sport Fisheries and Wildlife (BSF & W) to seek assistance from the
Federal Water Quality Administration (FWQA, formerly Federal Water
Pollution Control Administration) to define the problem and recommend
methods for correction.
Problems associated with hatchery discharges are not unique to
the Pacific Northwest. Investigations in other parts of the country
have dealt with similar problems. Data from these studies were used
when applicable.
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2
Authori ty
Section 5(a) of the Federal Water Pollution Control Act, as
amended, and Executive Order No. 11507 authorizes FWQA to assist
Federal agencies with waste disposal problems.
In a letter dated December 24, 1968, the Program Director of
BCF requested the Regional Director, FWQA, Northwest Region to con-
duct a survey of hatchery pollution problems. (Appendix).
Scope
The study area, illustrated in Figure 1, included the States of
Idaho, Oregon, Washington and western Montana. Primary attention was
given to four hatcheries which were selected as representative of
hatcheries in the study area, Eagle Creek National Fish Hatchery,
near Estacada, Oregon; Abernathy Creek Salmon Cultural Laboratory,
near Longview, Washington; Little White Salmon National Fish Hatchery,
near White Salmon, Washington; and Dworshak National Fish Hatchery
at Asahka, Idaho. All four of these hatcheries are operated by
BSF & W.
Objectives
The objectives of the study were to answer the following
questions:
1. What is the total waste load produced by fish hatcheries in
the study area?
2. What are the waste characteristics of fish hatchery
effluents?
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SALMON CULTURAL LABORATORY
DWORSHAK NATIONAL FISH HATCHERY
1 ll ~&
LITTLE WHITE SALMON
NATIONAL FISH HATCHERT
EAGLE CREEK NATIONAL
FISH HATCHERY
N E VkA D> '?
*- —
FEDERALLY OPERATED HATCHERY
STATE OPERATED HATCHERY
UNITED STATES DEPARTMENT Of THE INTERIOR
F«d»rel Wottr Pollu11or> Conrrol Admimitratien
durg 6/-fey POHtLANQ, OREGON
Figure 1
Location of Salmonid Hatcheries in the Pacific Northwest Indicating Those Surveyed
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4
3. What effect does the discharge of hatchery wastes have on
receiving waters?
4. What methods are available for controlling wastes from fish
hatcheries?
Acknowledgements
Acknowledgement is made of the valuable assistance and guidance
provided by the BSF & W and the BCF.
Thanks are expressed also to the personnel at the four hatcheries
surveyed.
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SUMMARY
Findings and Conclusions
1. Approximately 23 tons of Biochemical Oxygen Demand (BOD), with
a population equivalent of approximately 270,000, are discharged
per day by the 114 Federal and State hatcheries in the study
area.
2. Waste concentrations of hatchery effluents are small; however,
total pounds discharged per day can be of significant magnitude.
3. Hatchery discharges increase Chemical Oxygen Demand (COD), total
phosphorus (TP), orthophosphate, total kjeldahl nitrogen (TKN)
and ammonia nitrogen by 2.0, .036, .015, .20, and .058 lbs/100
Ibs fish/day, respectively.
4. Hatchery discharges can result in increased productivity in
receiving waters.
5. Hatchery discharges can increase the coliform bacteria count in
receiving waters to a small degree.
6. The discharge of waste resulting from the flushing of raceways
adds large amounts of solids and BOD to receiving waters.
7. Fish hatchery wastes are extremely amenable to biological treat-
ment.
8. The quantity and pollutional effects of hatchery wastes can be
greatly reduced when a water reconditioning/reuse system, in-
cluding sedimentation of skimming and backwash water is utilized.
9. A water reconditioning/reuse system employing an oyster shell
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filter converts virtually all of the ammonia nitrogen to the
nitrate and nitrate forms, as well as stabilizing pH, and
removing a portion of the solids.
10. Approximately 92 percent of BOD, 89 percent of suspended solids
(SS), 76 percent of TKN, and 84 percent of TP can be removed
from filter backwash water with 30 minutes of settling. These
removal efficiencies exceed the requirements for secondary
treatment.
11. The impact of hatchery discharges depends upon the quantity and
quality of the receiving water.
Recommendations
Hatcheries must be considered as a waste source. Water pollution
control measures should be considered for new hatcheries and at
existing hatcheries on a priority basis. Discharges from Federal
fish hatcheries must comply with applicable water quality standards
in accordance with Executive Order 11507.
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HATCHERIES SURVEYED
Salmon Cultural Laboratory
The Salmon Cultural Laboratory operated as a research hatchery
by the BSF & W, is located on Abernathy Creek, near Longview,
Washington.
About 22,000 pounds of fall chinook are raised annually at the
Salmon Cultural Laboratory. In addition, research is carried out
in areas such as fish diet, fish stamina, water supply, water steri-
lization, etc. One major development emanating from the laboratory
was a water reconditioning/reuse system developed by Burrows (4).
The system employs three 750 sg. ft. oyster shell filters which
biologically convert the ammonia (NH3) in the water to nitrates
(N03-). The water from the filter is then passed through an
aeration tower which strips out the carbon dioxide (C02) and adds
dissolved oxygen (DO). Discussion of this reconditioning/reuse
system is presented in the section entitled "Treatment Methods and
Needs."
The Salmon Cultural Laboratory obtains its water from wells.
The water is aerated, filtered for iron removal, and then heated or
cooled to bring the total sytem to the optimum temperature for fish
production. The make-up water at the Salmon Cultural Laboratory runs
about 5 percent, or 90 gallons per minute (gpm) for the 1800 gpm
system.
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8
Wastes from the Salmon Cultural Laboratory, consisting of 5
percent of the raceway effluent and backwash from the oyster shell
filters, are discharged without treatment into Abernathy Creek.
The Salmon Cultural Laboratory uses automatic feeders. These
disperse feed at 15-minute intervals. While moist pellets are used
at the present, a change to dry pellets is planned for the near
future. The possible effects of this change on water quality are
not known.
Eagle Creek National Fish Hatchery
The Eagle Creek National Fish Hatchery is located on Eagle
Creek, a tributary of the Clackamas River, 13 miles east of Estacada,
Oregon.
This hatchery has two sections. The upper section consists of
three banks of rearing ponds, each with 12 raceways. The lower
section includes the hatchery, three banks of rearing ponds, each
with 13 raceways, plus the fish ladder, holding pond, and spawning
facilities.
Water for this hatchery is obtained solely from Eagle Creek and
is used without treatment. Obtaining an adequate supply from this
source is a large problem at the hatchery, especially during the dry
summer months. When the water supply becomes extremely low, fresh
water is added only at the head end of the upper section, and the
water passes in series through both the upper and lower sections
before discharge. When the water supply is normal, each raceway
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9
receives fresh water. Water temperature is also a problem at the
hatchery, as low winter temperatures severely retard fish growth.
Wastes from the rearing ponds, holding pond, and hatchery room
are discharged without treatment into Eagle Creek.
During 1969, 46,000 pounds of silver salmon, 43,000 pounds of
spring chinook salmon, and 27,000 pounds of steelhead were raised at
the Eagle Creek Hatchery. The heaviest fish load at the hatchery is
during late summer and early fall.
The feed used at the Eagle Creek Hatchery is a moist pellet.
Feeding is accomplished by hand, and frequency of feeding varies
from hourly for small fish to two or three times a day for larger
fish.
Little White Salmon National Fish Hatchery
The Little White Salmon National Fish Hatchery, is located in
the State of Washington on the Little White Salmon River about one
mile above its confluence with the Columbia River.
The facility has two sections. The upper section is composed
of the fish ladder, holding ponds, spawning facilities, and 41 rear-
ing ponds. The lower section includes the hatchery room, six rearing
ponds, and a water reconditioning/reuse system. The water recon-
ditioning/reuse 'system is used only for the hatching of eggs. It
consists of three rearing ponds converted to oyster shell filters and
an aeration tower.
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The hatchery utilizes three water supply sources: two springs
and the Little White Salmon River. This water is used without treat-
ment. Fish are reared in spring water and converted to river water
before release. Water supply at the hatchery has never been a problem
from the standpoint of either quantity or quality, and all ponds are
run on a once-through basis.
The wastes from the rearing ponds, holding ponds, and the
hatchery room are discharged without treatment into Drano Lake, a
backwater on the Little White Salmon.
During the year 1969, 70,000 pounds of fall chinook, 13,000
pounds of spring chinook and 32,000 pounds of silver salmon were
raised at the Little White Salmon National Fish Hatchery. The
heaviest fish load at the hatchery is from December to January.
During summer months only 20 of the total 56 rearing ponds are uti-
lized; however, the same pond loadings are used as during months of
heavy loads. These loadings run from 7 to 12 pounds of fish per
cubic foot of tank, with a flow of approximately 470 gpm per tank.
The feed used at the hatchery is the moist pellet. Feeding is
done by hand about twice per day.
Dworshak National Fish Hatchery
Dworshak National Fish Hatchery is located in Asahka, Idaho, at
the mouth of the North Fork Clearwater River.
This facility, less than a year old, is the largest hatchery
presently utilizing a water reconditioning/reuse system. The hatchery
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has 84 rearing ponds, 25 of which are on the reuse system. The
ultimate plan calls for 50 ponds on reuse and 34 on river water.
Eight oyster shell filters, each with a surface area of 1650 sq. ft.
are used for treatment of the rearing pond effluent. Eight additional
filters are planned for the 25 ponds to be added to the reuse system.
Water for make-up in the reuse system and for the ponds not on
the system comes from the North Fork Clearwater River. Make-up
water for the reuse system is filtered and sterilized with ultra-
violet light before it is combined with the reconditioned water from
the oyster shell filters. At the present time, the make-up water
constitutes ten percent of the total water in the system.
Backwash water from the oyster shell filters, hatchery room
wastes, and effluent from the rearing ponds not on the water reuse
system is discharged without treatment into the North Fork Clearwater
River.
Although the hatchery has not operated for a full year, the
calculated production for fiscal year 1970 is 295,000 pounds. For
fiscal years 1971 and 1972, production is estimated at 520,000 and
620,000 pounds, respectively. The majority of fish raised are
steel head; rainbow trout make up the rest.
Dworshak uses an automatic feeding system. Moist pellettzed
food ts now used; however, a conversion to a dry pellet is expected
in the near future. Frequency of feeding varies with the size of the
fish, ranging from once an hour for small fish to four times per day
for the large fish.
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SAMPLING PROGRAM AND ANALYTICAL METHODS
Sampling sites were selected to determine incremental changes
in the water quality through individual rearing ponds, a group of
ponds, or the hatchery as a whole. Table 1 lists the sampling sites.
Stream sampling was done above and below two hatcheries to measure
pollutional effects and stream recovery.
For the most part, grap samples were taken for analysis. One
24-hour composite was made with physical-chemical samples taken every
two hours and bacteriological samples taken every four hours.
Biological sampling was done in the receiving stream above and
below Eagle Creek Hatchery to assess the effects of hatchery dis-
charges on the aquatic community. Biological.samples were collected
with a Surber- sampler, preserved in the field with ten percent
formalin, and returned to Portland to be identified and enumerated.
Physical-chemical and bacteriological samples were collected
with a Kemmerer sampler. The bacteriological samples were iced and
sent to the FWQA, Pacific Northwest .Water Laboratory (PNWL) in
Corvallis, Oregon, or returned to Portland to be incubated and
analyzed. During the 24-hour composite, bacteriological samples
were incubated and analyzed in the field.
Dissolved oxygen and temperature were measured in the field.
V Use of product and company names is for identification only
and does not constitute endorsement by the U.S. Department of the
Interior or the FWQA.
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TABLE 1
HATCHERY SAMPLING SITES
Abernathy Creek Salmon Cultural Laboratory
Station 1 Well water after treatment
2 Rearing Pond effluent - influent to filter
3 Filter effluent
4 Aeration tower effluent
5 Filter backwash water
6 Abernathy Creek above hatchery
7 Abernathy Creek - 30 yards below hatchery
8 Abernathy Creek - 3 miles below hatchery
Eagle Creek National Fish Hatchery
Station 1 Hatchery influent water
2 Upper Pond effluent
3 Lower Pond effluent
4 Eagle Creek between Upper and Lower Ponds, below
upper bridge
5 Eagle Creek - 50 yards below hatchery, below lower
bri dge
6 Eagle Creek - 3.4 miles below hatchery
Little White Salmon National Fish Hatchery
Station 1 Upper pond influent
2 Upper pond effluent
3 Spring Water
• 4 Lower pond influent
5 Lower pond effluent
Dworshak National Fish Hatchery
Station 1 Hatchery influent before treatment
2 Hatchery influent after treatment
3 Rearing pond effluent - influent to filter
4 Filter effluent
5 Filter backwash water
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The Alsterberg (Azide) modification of the Winkler Method'was used
for DO determinations and a laboratory thermometer was used for
temperature.
All other samples were sent to the PNWL for analysis. Nutrient
samples were preserved in the field with mercuric chloride (HgCl2).
COO and Total Organic Carbon (TOC) samples were preserved in the
field with sulfuric acid (HgSO^. Samples for BOD analysis were
preserved by icing before shipment. Upon arrival at the PNWL, BOD
samples were set up and Incubated at 20° C.
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WASTE CHARACTERISTICS
Wastes from fish production are from metabolic waste products
and residual food. The metabolic products consist mainly of ammonia-
nitrogen and urea (5). These products vary in amount depending on
water temperature, size arrd species of fish, type and amount of food
consumed, etc.
Excess food is also a source of wastes. Residual food sinks to
raceway bottoms where the soluble portion leaches out. The remain-
der of this food ends up in the receiving water when raceways are
periodically flushed out.
Physi cal-Chemi cal Characteri sti cs
Of primary concern were the physical-chemical characteristics
of hatchery effluents. These effluents include, for the most part,
the normal raceway discharges and the backwash water from a hatchery
employing a water reconditioning/reuse system. The parameters
measured included temperature, dissolved oxygen, BOD, COD, nutrients,
total and fecal coliforms.
Hatchery effluents were characterized by analysis of both grab
and composite samples. For'the most part, grab samples were taken.
One set of 24-hour composite samples were collected, however, so
that diurnal changes could be noted. To reduce the data for
comparisons among hatcheries, the waste units of lbs/100 Ibs
fish/day were used. Because of the large flows encountered at the
hatcheries surveyed, incremental changes were small and in many cases
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were lass than analytical accuracy. For this reason wide variations
can be noted in the data. An average of the data, however, reveals
answers comparable to the findings of other studies of a similar
nature.
Figure 2 shows a daily record of temperature for five sampling
stations at the Eagle Creek Hatchery. This record shows a rather
large (6.5° C) diurnal change in temperature. No significant change
in temperature is noted through the hatchery.
Concurrently with temperature, dissolved oxygen was measured
every two hours at Eagle Creek. Figure 3 indicates results of these
analyses. While no significant change is noted through the total
hatchery, a definite decrease is shown through the upper ponds.
Figure 4, which indicates only,the upper pond influent and effluent
DO's, shows this most clearly. Here, an average decrease of
0.6 mg/1 for the period surveyed can be noted. The reason that a.
similar decrease was not measured through the lower pond is that the
lower pond effluent passes through a holding basin (which contains
three small aerators) and through the fish ladder before it is
discharged to Eagle Creek.
Table 2 contains data collected at Eagle Creek and the Little
White Salmon Hatchery. Averages for COD, SS, orthosphosphate, TKN,
and NH3-N in IDS per 100 Ibs of fish per day ran 2.0, 0.026, 0.015,
0.20 and 0.058, respectively. No BOD samples were taken at Eagle
Creek or Little White Salmon, but the COD value of 2.0 lbs/100 Ibs
fish/day correlates well with the BOD value of 1.34 lbs/100 fish/day
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FIGURE 2. Diurnal Temperature Curves for Five Stations at the Eagle Creek Hatchery.
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FIGURE 3. Diurnal Dissolved Oxygen Curves for Five Stations at the Eagle Creek Hathcery.
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FIGURE 4. Diurnal Dissolved Oxygen Curves for Upper Pond Influent and Effluent at the Eagle Creek Hatchery.
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TABLE 2
WASTE LOADING FACTORS OF HATCHERIES SURVEYED WITH RECONDITIONING/REUSE
#/100# Fish/Day
Hatchery
Eagle Creek!/
Eagle Creek!/
Little White Salmon
Little White Salmon
Eagle Creek
Eagle Creek
Eagle Creek
Eagle Creek
Little White Salmon
Little White Salmon
Locati on
Upper
Lower
Upper
Lower
Upper
Lower
Upper
Lower
Upper
Lower
Ponds
Ponds
Raceway
Raceway
Ponds
Ponds
Ponds
Ponds
Raceway
Raceway
Date
7/17/69
7/17/69
8/14/69
8/14/69
8/28/69
8/28/69
9/11/69
9/11/69
9/16/69
9/16/69
Pounds
Fish
4,000
6,500
1,337
1,337
7,700
12,700
14,600
14,400
1,581
1,581
Averages
Flow
mgd
7
8
7
8
7
7
.8
.4
.68
.68
.8
.4
.1
.7
.68
.68
Total
COD Phosphorus
3.2
6.5
—
—
.84
0
.82
.88
2.0
.037
.015
.069
.042
.076
.019
.016
.023
.027
.036
Orthophosphate TKN
.019
.006
.032
.003
.043
.011
.010
.015
.001
.005
.015
...
—
.21
—
.50
.22
.17
.13
.07
.07
.20
NH3-N
.080
.120
.050
.074
.040
.015
.025
.058
a/ 24-hour composite sample
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reported by Kramer, Chin and Mayo (1) In a study of a Washington
trout hatchery.
Bacteriological samples were taken during the 24-hour study at
Eagle Creek. Samples were collected every four hours and analysed
for total and fecal coliforms. Figure 5 shows total coliform counts
for the five sampling sites. The data show that a source of con-
tamination existed above the hatchery during the first few hours of
sampling. Comparison of values from above and below the hatchery
suggests that regrowth of coliforms may be occurring as a result of
the hatchery discharge.
A large amount of the waste from hatcheries results from the
flushing of solids from the raceways. Huber and Valentine (3)
measured 2.7 pounds of BOD and 8.9 pounds of total solids from the
flushing of one raceway which contained a seven-day accumulation of
solids. They also showed that 93 percent of the solids could be
removed with 15 minutes of detention time.
Hatcheries utilizing water reconditioning/reuse systems have two
primary sources of waste. These are filter backwash water and the
raceway effluent, used as skimming water for the filters. Skimming
water is discharged to allow for the addition of 5 to 10 percent
make-up water. It is approximately equal in volume to the amount of
make-up water minus the amount of water used in the backwashing
process.
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i'pmiijmi'Miiiiiiii^
:;-r: :r:: :-;1':-: ;':-,;;-: ±^i-^-lu^^i;^:i^;i^l-iiil : Tffl-iit.-i;
FIGURE 5. Diurnal Total Colifonn Counts for Five Stations at the Eagle Creek Hatchery.
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Backwash wastes were analysed at two of the hatcheries surveyed.
The results of the analyses are in Table 3. The wastes from the two
hatcheries were very similar with respect to DO, BOD, COD, and
nitrogen compounds. The Salmon Cultural Laboratory waste had higher
total solids but was lower in suspended solids than the Dworshak
waste. The Salmon Cultural Laboratory waste also had a high total
coliform count (43,000/100 ml). Both five-day and ultimate BOD
values for the two hatcheries are almost identical. For the Salmon
Cultural Laboratory and the Dworshak Hatchery, five-day values were
31 and 36 mg/1, and ultimate values were 160 and 150 mg/1, respec-
tively. Figure 6 shows a plot of BOD vs time for each of the two
backwash wastes. While the Salmon Cultural Laboratory waste showed
a definite carbonaceous and nitrogeneous demand, the waste from
Dworshak did not. This disparity may have been caused by holding the
Dworshak sample in an iced condition for a longer period of time
before incubation.
To assess the removal efficiencies of settling, and to obtain
some design criteria, settling tests were run on the filter backwash
water from the Dworshak Hatchery. Each test consisted of filling
two 1,000 ml graduated cylinders with backwash water and allowing
the solids to settle out. One graduate was run 30 minutes and the
other 60 minutes. At these times the supernatent was siphoned off
for analysis. The results of these analyses were compared with
those for the backwash water which are listed in Table 3.
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TABLE 3
WASTE CHARACTERISTICS OF OYSTER SHELL
FILTER BACKWASH WATER
Salmon Cultural Dworshak National
Laboratory Fish Hatchery
5/22/69 12/17/69
Temperature, C 16.0 13.5
Dissolved Oxygen, mg/1 9.6 8.8
5 Day BOD, mg/1 31 36
Ultimate BOD, mg/1 155 152
COD, mg/1 91 81
TOC, mg/1 4 16
Total Solids, mg/1 314 171
Total Volatile Solids, mg/1 152
Suspended Solids, mg/1 10 34
Total Phosphorus, mg/1 as P 4.4 1.6
Orthophosphate, mg/1 as P 0.58 0.38,
NH3-N, mg/1 as N .1 0.13
N02-N, mg/1 as N <0.05 0.033
N03-N, mg/1 as N 3.6 2.4
TKN, mg/1 as N 3.8 4.7
Total Coliform, per 100 ml 43,000
Fecal Coliform, per 100 ml <2
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iifpi
luuiiu
11 i 1.1 U.U.
FIGURE 6. Filter Backwash Water BOD Curves.
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Removal efficiencies for the 30 and 60 minute tests, as well
as the analysis for the 60 minute test, are shown in Table 4. These
data show a significant reduction of SS, BOD, TKN, and TP in the
first 30 minutes of settling, with little additional removal in the
next 30 minutes. The close correlation between BOD, TKN, TP and the
SS removals indicates that BOD, TKN, and TP are associated with the
solids. In contrast to TP, removals for the orthophosphates were
small. This is because orthophosphates are usually in a soluble
form.
TABLE 4
REMOVAL EFFICIENCIES OF SETTLING FOR BACKWASH WATER
Suspended Solids
5 Day BOD
Total Kjeldahl Nitrogen as
Total Phosphorus as P
Orthophosphate as P
% Remova
30 minutes 60
89
92
N 76
84
38
1
mi nutes
90
94
83
85
38
Final Effluent
cone. @ 60 min., mg/1
3
2
1.2
0.2
0.2
Although most of the removals were accomplished in the first
30 minutes, it must be emphasized that these were static tests per-
formed under quiescent conditions. Detention times approaching 60
minutes would be advisable for the design of a continuous flow-
through system.
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Total Waste Load
The estimated total waste load per day produced by all the
Federal and State hatcheries in the study area was computed by
employing average waste loading factors presented in Table 2 and
in "reference 1.
BOD5 1.3 lbs/100 Ibs fish/day (1)
TKN 0.20 lbs/100 Ibs fish/day
TP 0.036 lbs/100 Ibs fish/day
Applying these factors to the 8.6 million pounds of fish
raised annually in the 114 Federal and State hatcheries in the study
area, it has been calculated that approximately 23 tons of BOD are
discharged per day. This discharge is roughly equivalent to raw
sewage from a city of 270,000 people. In addition, 8,600 pounds of
TKN and 1,500 pounds of TP are added daily to receiving waters.
The amount of pollutants discharged by each hatchery is not
extremely large; however, it becomes significant when the receiving
body of water is small.
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EFFECTS ON WATER QUALITY
Physical-Chemical Effects
To assess the effects of hatchery discharges on receiving water
quality, stream sampling was undertaken at the Eagle Creek Hatchery
and the Salmon Cultural Laboratory. Since the Dworshak and Little
White Salmon Hatcheries discharge their effluents into extremely
large bodies of water it was considered impractical to assess the
effects on water quality of these hatcheries.
Two sampling surveys were made at Eagle Creek and one at
Abernathy Creek. Grab samples were taken above and below each
hatchery as well as a few miles downstream. The downstream samples
were to check for persistence of pollution and to assess stream
recovery, if any.
Table 5 presents data for the two Eagle Creek surveys. During
each of these surveys, essentially the entire flow of Eagle Creek
was utilized by the hatchery.
Data from the August 28 survey at Eagle Creek show an increase
in temperature, total solids, COD, N02-N, N03-N, TKN, total phos-
phorus, and total coliforms, as well as a decrease in DO as a result
of the hatchery discharge. About 100 yards downstream from the
hatchery the odor of ammonia was highly noticeable. At a point 3.4
miles downstream the dissolved oxygen levels had returned to those
measured above the hatchery and the total solids were reduced. The
nutrients, especially nitrate nitrogen, were still high. The great
-------
TABLE 5
HATCHERY DISCHARGE EFFECTS ON WATER QUALITY OF EAGLE CREEK
Temperature, °C
Total Solids, mg/1
DO, mg/1
COD, mg/1
N02-N, mg/1
N03-N, mg/1
NH3-N, mg/1
TKN, mg/1
Total Phosphorus, mg/1
Total Coli form /100 ml
Fecal Coli form /100 ml
Above
Hatchery Intake
13.0
109
10.4
4
<0.01
0.05
0.2
0.010
78
16
8/28/69
50 yds. Below
Hatchery
14.0
145
9.8
5
<0.01
0.07
0.5
0.048
90
4
3.4 mi. Below
Hatchery
14.8
108
10.0
3
<0.01
0.22
0.4
0.028
240
120
Above
Hatchery
15.0
53
10.0
<1
<0.01
0.08
0.06
0.2
0.011
124
4
9/1 1/69
50. yds. Below
Hatchery
15.8
72
9.0
4
<0.01
0.12
0.16
0.7
0.75
970
8
3.4 mi . Below
Hatchery
15.8
69
10.0
13
0.01
0.42
0.06
0.2
0.04
820
2
-------
33
increase in nitrate nitrogen resulted from the conversion of ammonia
to this form. Although an increase in total coliforms was measured
at the downstream station, it is impossible to determine with the
available data if this increase is due to regrowth or a secondary
source.
Data from the September 11 survey at Eagle Creek are also pre-
sented in Table 5. These data further substantiate the findings of
the August 28 survey. The ammonia odor was again apparent below the
hatchery. As in the August survey, there was an increase in NOs at
the 3.4 mile station, which correlates with the reduction in ammonia.
Table 6 contains the data obtained in the survey of Abernathy
Creek, which receives the discharge from the Salmon Cultural Labora-
tory. These data show about the same results as the Eagle Creek
data, except to a lesser degree. This is because the hatchery dis-
charge constitutes only a portion of the total streamflow.
Biological Effects
A survey was conducted at the Eagle Creek National Fish Hatchery
to assess the effects of hatchery discharges on the biota of a
receiving stream. Four Surber samples were collected at each of
three stations. These stations were selected on the basis of geo-
logic and hydraulic similarity. Table 7 lists the organisms found
at each of the three stations. A description of the station location
and observations of the benthos follows Table 7.
-------
34
TABLE 6
HATCHERY DISCHARGE EFFECTS ON WATER QUALITY OF ABERNATHY CREEK
5/22/69
Temperature, °C
Total Solids, mg/1
DO, mg/1
TO'C, mg/1
pH
N02-N, mg/1
N03-N, mg/1
TKN, mg/1
Total Phosphorus, mg/1
Total Coli form /I 00 ml
Fecal Coli form /100 ml
Above
Hatchery
13.8
24
10.7
<1
6.3
<0.1
0.1
0.2
0.2
54
6
30 yds. Below
Hatchery
13.0
46
10.4
2
5.9
<0.1
0.1
0.2
0.2
530
8
3 mi . Below
Hatchery
13.5
40
10.6
1
5.8
<1
<0.1
0.2
0.1
230
8
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TABLE 7
EAGLE CREEK BIOLOGICAL DATA
Organisms
Stone flies (nymphs)
Perlodidae
Peril dae
Nemourida
Pel toper! idae
Mayflies (nymph)
Baeti dae
Ephemeridae
Heptageniidae
Leptophjebiidae
Caddisflies
Glassosomatidae
Hydropsychidae
Limnephilidae
Phyacophilidae
Hydroptilidae
Brachycentridae
Trueflies
Tendipediead
Mel ei dae
Rhagionidae
Similiidae
Ti puli dae
Tabanidae
Beetles
El mi dae
Psephenidae
Amphizoidae
Scuds
Gammeridae
Sow Bug
As el li dae
Mite
Crayfish
Astacidae
Snails
Physidae
Larvae
Pupae
Larvae
Larvae
Pupae
Larvae
Pupae
Larvae
Pupae
Larvae
Larvae
Pupae
Larvae
Larvae
Larvae
Pupae
Larvae
Pupae
Larvae
Larvae
Larvae
Adult
I
13'
7
2
5
23
21
16
7
7
2
19
3
3
11
6
8
1
3
11
6
2
1
2
1
5
1
5
4
1
2
4
1
14
1
0
Station
II
67
14
17
0
201
32
60
0
10
0
36
1
6
30
1
0
0
0
98
14
4
1
4
0
10
7
0
8
0
0
0
0
0
0
0
III
41
12
0
0
125
6
91
2
2
1
43
1
1
13
5
0
0
0
12
1
0
0
3
0
3
0
0
12
0
0
0
0
0
1
8
-------
36
Station 1
This station was located several hundred yards upstream from
the submerged weir control dam used for diversion of the hatchery
water supply system. Half of the stream bed at this location was
boulders and bedrock the rest was packed gravel, small rocks, and
very coarse sand. About half the boulders and gravels were covered
with diatoms. Green algae growth at the station was very scarce.
The benthic animal community consisted of only modest numbers
of many diversified kinds of fauna. This diversified community
included mayflies, stoneflies, true flies, caddisflies, beetles,
mites, isopods, and crayfish.
Station 2
Station 2 was located about 150 yards below the hatchery's
lowest outfall. Here the stream bed was mostly bedrock and smooth
boulders resulting from annual scouring. The water at this station
was slightly milky in appearance and the air had an odor of ammonia
and dead fish. The sand in the eddies was covered by silt, fish
feces, and fish food. Dead salmon and trout fingerlings and lamprey
carcasses were noted in most of the eddies and caught on some of the
rocks. The lamprey had died from natural causes. From their
appearance and location, it was concluded that some of the dead
salmon fingerling had been flushed from the hatchery ponds and the
remainder had died in Eagle Creek below the Hatchery from unknown
causes.
-------
37
The majority of the rocks and smooth rubble supported benthie
life. Most of the aquatic Insects were strainer types such as midges
and caddisflles which were present In greater than modest numbers on
some of the smaller rocks. In general, the benthic community at
this station was less diverse than at Station 1, but of greater
numbers.
Station 3
Station 3 was located approximately 3.4 miles below the hatchery.
Here the stream bottom was covered by boulders, rubble, and coarse
gravel. The water was a light brown, but was clear. Lamprey
carcasses were particularly abundant, but no dead salmon or trout
fry or fingerlings were observed. All of the submerged boulders,
rubble and gravels were covered with diatoms. Clumps of filamen-
tous green algae were observed. These clumps of algae contained
mayflies, stoneflies, isopods, amphypods, mematods, and many kinds
of true fly larvae. In addition, crayfish, beetles, snails, and
caddisflies were found on and under the rubble and coarse gravels.
Snails, mayflies and diatoms were particularly abundant at this
station.
-------
TREATMENT METHODS AND NEEDS
Water Reconditioning/Reuse
During the past decade, much work has been done in the field of
controlled environment for fish propagation. This approach offers
great promise in maximizing production.
Because different species have varying environmental require-
ments, flexibility is needed. This flexibility is most dependent
upon the water supply. Burrows and Combs (4) list five major cri-
teria for a potential water supply; quality, quantity, temperature,
disease incidence—low or absent, and location near the outlet for
release. Natural sites which meet all of the above criteria are
nonexistent. Therefore, a solution is needed to alter those factors
which are not suited for optimum production.
One solution which has proved successful is a water recondition-
ing/reuse system using 5 to 10 percent make-up, developed by Burrows
and Combs (4). With this reduced water requirement, problems of
quality, temperature control and sterilization become economically
feasible. The major problem encountered in the development of a water
reconditioning/reuse system was the gradual build-up of metabolic
waste which became toxic to the fish. The main metabolic products as
mentioned earlier are urea and armonia (NH3). Burrows (5) found that
at stocking rates of less than 5 pounds of fish per gpm, urea was
the dominant excreatory product; at higher rates ammonia became
dominant. In addition, he found that whereas urea exhibited no
-------
40
deleterious effects, concentrations of un-ionized ammonia as low as
0.006 ppm in continuous exposure became toxic to fish. To correct
this problem, a treatment system was devised consisting of a biolo-
gical filter followed by aeration. A schematic drawing of this
system is shown in Figure 7. The heart of the system is the
biological filter which is shown in detail in Figure 8. This filter
is composed of 4 feet of crushed rock overlain by 1 foot of oyster
shell. The crushed rock provides a surface for the growth of
nitrifying bacteria which convert the toxic ammonia or ammonium ion
(NH^) to nitrate ions (NOp which are non-toxic. In making this
conversion, 2 moles of oxygen are required to convert each ammonium
ion to a nitrate ion, as shown in the following equations:
Nitrosomonas
NHj + 1.502 *- 2H+ + H20 + N02
Nitrobacter
N02 + .502 "~NOs
The oyster shell which overlies the crushed rock serves many
functions. It keeps the pH adjusted as the C02 produced by the fish
and the NO^ produced by the bacteria create an acidic condition.
In addition to stabilizing pH, the oyster shells trap the larger
solids and provide a large amount of trace minerals required by the
ni tri fyi ng bacteri a.
Filter influent and effluent samples were taken at both Dworshak
and the Salmon Cultural Lab. The analyses showed that ammonia
nitrogen is reduced and that nitrate nitrogen and nitrite nitrogen
are increased. In addition, a decrease in suspended solids was noted
-------
41.
- I
2
V]
Ji
5
*> V
-fc§
Aeration Tank
"1
Filter
30-
30"
20" '
Header (Total Flow 150 to GOO GPM/Pound)
j—Reu
Line
•Waste from Ponds
75'x 17'Reel. Circul. Rearing Ponds
PLAN
Alternate Source
of •*!»/*/•
20-75'x 16' Rect. Circul. Rearing Ponds
'30* Drain Lines
SECTION
Aeration :
Each Aspirator passes
125 GPM at 10 psi
11,400 GPM Requires 92
Aspirators.
Each Aspirator Requires
4 so;, ft. of Area. 92 Aspi-
rator 3€8 to., ft. Aeration Tank
Capacity:
I.OOO,OOO Fish at lO/lo. or 4.OOO.OOO fish at SO/lb.
or 5,400,000 Fish at 90/lb.
Ponds:
Twenty 75' Ponds at 600 GPM* 12,000 GPM in Circulating
System. I2,OOO at 5%-€OO GPM Supplemental Water ft'q'd.
Filters:
Each 1,500 sq. ft. Filter Posses 1,500 GPM
Eight Filters at I,50O GPM* 12,000 GPM.
FIGURE 1. Schematic Drawing of a Typical Controlled
Environment System for Rearing Salmonlds (4).
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42
PLAN VIEW OF FILTER
Inlet S/w'ct Safe Operated
by SoffOtd Operated Air Cjfl.
0.
ll
Normal W. S. •
».S. When Washing-
0/sler Shell
Crushed Raft
l/Z'to 3' Sir*
1/4 to 3/4 Sin
1/a'HcJet of 3"
Ctrs. /" from
Blm. 8 Stagger^
L
Filtered Water Header. 1/Z Holtt /
at 4S* from 81m.
Total Number * 4,000 find. Cross-Header}
9" Air Header
Filtered Water J
Suction Header^
Filtered Water
Pump
LONGITUDINAL SECTION THROUGH FILTER
FIGURE 8. Design Drawing of a Water Reclamation Filter (4).
-------
43
across the filter at Dworshak (Table 8).
TABLE 8
OYSTER SHELL FILTER WASTE TREATMENT
Salmon Cultural Lab
5/22/69
Influent Effluent
Total Solids, mg/1
NH3-N, mg/1
N02-N, mg/1
N03-N, mg/1
pH
DO, mg/1
BOD, mg/1
COD, mg/1
198
0.11
0.05
3.5
6.2
7.3
2
6
198
0.02
0.05
3.7
7.0
6.7
<2
4
Dworshak Hatchery
12/17/69
Influent Effluent
227 171
0.08 0.05
0.03 0.05
2.2 2.4
-
-
-
-
Following the filter, the water is aerated to replace the
dissolved oxygen used by the fish and the bacteria. This aeration
also strips off any COg gas that is present.
The accumulation of solids and growth of Sphaerotolus necessi-
tate backwashing the filter about once or twice a day under maximum
fish loading. This backwash water and the skimming water constitutes
the effluent streams for a hatchery using a water reconditioning/reuse
system of this type.
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44
Other Treatment Methods
Related studies on hatchery waste problems have led to schemes
which differ from those of the water reconditioning/reuse system out-
lined in the previous section. Parker and Associates' studies of
the Rifle Falls Trout Hatchery in Colorado (2) led to the design of
a treatment system which includes high-rate trickling filters,
chemical additions, final sedimentation, and solids decomposition.
The filters were designed for 20 million gallons (MG) per acre per
day (.32 gpm/ft2) without recirculation. Activated carbon and
potassium permanganate are added to remove taste and odor, followed
by a final settling basin with a 1 to 1% hr. design detention time.
Disposal of solids from the settling basin is accomplished in an
aerobic stabilization pond.
At the Jordan River National Fish Hatchery in Michigan, a study
undertaken by the Lake Michigan Basin Office, FWQA, (formerly FWPCA)
(3) recommended a treatment system employing only a settling basin
or lagoon for the removal of solids.
As stated earlier, a study by Huber and Valentine (6) at the
Lamar National Fish Hatchery in Pennsylvania recommended a settling
basin with a detention time of 15 minutes for treatment of the
hatchery wastes and an activated sludge system employing only 2 hours
of aeration time. Mechanical aerators are recommended for use in
the aeration basin, followed by a settling basin.
-------
45
Design Criteria
The design criteria outlined in this section are for a treat-
ment system incorporating an oyster-shell filter. Although other
systems may prove feasible, the oyster-shell filter is presently
used-and was the only treatment process analysed. In addition,
the system provides for the reuse of water which offers many
advantages. While doing an adequate job of renovating water for re-
use, the system does present some pollution problems through the
discharge of backwash and skimming water. For this reason, addi-
tional processes are needed in order to provide sufficient treatment
for discharges to receiving waters.
An adequate treatment system for a hatchery would consist of
three basic steps. These are filtration-aeration, sedimentation, and
solids handling.
The filtration-aeration step is explained in detail in a
previous section. Burrows and Combs (4) outlined the following
design criteria for the process:
Filter
p
Loading rate: 1 gpm/ft
Frequency of Backwash: Every other day 0 maximum loading
Duration of Backwash: 40 min. air agitation, 20 min.
of flushing
Blower capacity: 1.33 scfm/ft2 filter
-------
46
Aerators
Number: 1 aspirator per 125 gpm @ 10 psi
.Size: 4 ft^ of area per aspirator
The filters should be sized to handle the full hydraulic load
of the hatchery. This would prevent any solids from raceway flushing
entering the receiving water, besides providing the best effluent
possible.
The sedimentation step would be used for treatment of backwash
and skimming water from the filter. The sedimentation system could
be batch or continuous, depending on the size of the hatchery,
frequency of backwashing, space limitations, etc. As determined by
the settling tests explained previously, a detention time of 30 to
60 minutes is needed for a continuous system. Surface settling rates
for this settling basin should be from 700 to 900 gallons per day per
square foot.
The disposal of solids from the sedimentation step is the third
phase of treatment. This step can present the most difficult
problems. Many possibilities for treatment or disposal exist such as:
Land disposal
Insertion into domestic treatment system
Aerobic or Anaerobic Digestion
Concentration and Incineration
Land disposal, either at the hatchery or some other place, is a
relatively cheap and trouble-free method for disposing of solids.
-------
47
Being high in nutrients, these solids might be disposed of by
spreading them on the hatchery grounds.
If the hatchery is large enough to warrant a domestic treatment
system, the solids could be disposed of in this manner. The solids
are highly amenable to treatment and no problems should be encoun-
tered with this method as long as the domestic system is designed
hydraulically to handle the total flow.
Another method of disposal is some type of digestion system.
Parker (2) recommends an aerobic system; however, an anaerobic
system, such as a septic tank, could be used.
Incineration of solids, while effective, should be used only
when other methods are not available. It will offer the most
problems in terms of operation and maintenance as well as being
the most expensive to build.
-------
DEFINITION OF TERMS
Algae -- Simple plants, many microscopic, containing chloro-
phyll.
BOD ~ Biochemical Oxygen Demand. A measure of the amount of
oxygen required for the biological decomposition of dissolved
organic solids to occur under aerobic conditions and at a standard-
ized incubation time and temperature.
cfs -- Cubic feet per second.
COD — Chemical Oxygen Demand. A measure in terms of the amount
of oxygen required to chemically oxidize all organic compounds, with
a few exceptions, and some reduced inorganic compounds.
pp_ -- Dissolved Oxygen.
mg/1 — Milligrams per liter (1000 mg/1 = 1 gm/1).
Orthophosphate -- A stable form of phosphorus which is the only
available form for biological activity.
Phytoplankton — Plant microorganisms such as algae, living
unattached in the water.
Plankton -- Aquatic plant and animal organisms of small size,
mostly microscopic, that have relatively small powers of locomotion
or drift in the water subject to wave action and currents.
SS^ — Suspended Solids. Solids that float on the surface or are
in suspension in water, sewage or other liquids.
TKN -- Total Kjeldahl Nitrogen. Organic nitrogen and nitrogen
in the form of ammonia (NH3). Does not include nitrogen in the form
of nitrates (NOa-) or nitrites (N02-).
-------
50
TOC -- Total Organic Carbon. Reported as carbon (C).
TP_ -- Total Phosphorus. Phosphorus in organic and inorganic
forms. Phosphorus and nitrogen are nutrients necessary for main-
taining biological growth.
TS_ -- Total Solids. The sum of the suspended and dissolved
solids.
-------
51
BIBLIOGRAPHY
1. Anonymous, "A Study of the Pollutional Effects of Salmonid
Hatcheries," Kramer, Chin & Mayo, Consulting Engineers,
Seattle, Washington, June 1969.
2. Anonymous, "Preliminary Report for Treatment Facilities, Rifle
Falls Trout Hatchery," Parker & Associates, Consulting
Engineers, Greeley, Colorado, August 1968.
3. Anonymous, "Water Quality Conditions at the Jordan River
National Fish Hatchery, Elmira, Michigan, Department of
the Interior, FWPCA, Lake Michigan Basin Office, Great
Lakes Region, February 1969.
4. Burrows, Roger E. and Combs, Bobby D. "Controlled Environments
for Salmon Propagation," The Progressive Fish-Culturist,
Vol. 30, No. 3, July 1968.
5. Burrows, Roger E. Effects of Accumulated Excretory Products on
Hatchery-Reared Sal mom' ds. Department of the Interior,
Fish and Wildlife Service, Bureau of Sport Fisheries and
Wildlife, Research Report 66, 1964.
6. Huber, Richard T. and Valentine, Joseph J. Analysis and Treat-
ment of Fish Hatchery Effluents. Lamar National Fish
Hatchery Development Center, Lamar, Pennsylvania, 1968.
-------
APPENDIX
Letter of Request
-------
UNITED STATES
DEPARTMENT OF THE INTERIOR
FISH AND WILDLIFE .SERVICE
BUREAU OF COMMERCIAL FISHERIES
COLUMBIA FISHERIES PROGRAM OFFICE
811 N. E. OREGON STREET
P. O. BOX 4332, PORTLAND 8. OREGON 972O8
December 2k, 1968
Mr. James L. Agee, Regional Director
Federal Water Pollution Control Administration
501 Pittock Block
Portland, Oregon 97205
Dear Mr. Agee:
The wastes that are discharged from some of the fish hatcheries that
are operated with Federal funds on the lower Columbia Elver have be-
come nuisances during low flow in summer.
We believe that objectionable discharges should be corrected, and
would like to obtain your advice on how this might be best accom-
plished.
Could we meet with you or appropriate members of your staff to dis-
cuss this problem?
Sincerely yours,
Fred Cleaver
Program Director
-------
As the Nation's principal conservation agency, the Depart-
ment of the Interior has basic responsibilities for water, fish,
ivildlije, mineral, land, park, and recreational resources.
Indian and Territorial affairs are other major concerns of
America's "Department of Natural Resources."
The Department works to assure the wisest choice in manag-
ing all our resources so each will make its full contribution
to a better United States—now and in the future.
------- |