Volume 2 Sockeye Salmon Studies on the Nechako

VOLUME 2

SOCKEYE SALMON STUDIES ON THE NECHAKO RIVER RELATIVE TO THE POTENTIAL KEMANO I1 POWER DEVELOPMENT.

INTERNATIONAL PACIFIC SALMON FISHERIES COMMISSION NEW WESTMINSTER, B.C.

FEBRIJAKY , 1979 Although the major part of the funding for these studies was provided by the Bitish Columbia Hydro and Power Authority, the findings and opinions expressed wihin the report are solely

those of the author agency. TABLE OF CONTENTS

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Introduction Nechako River Sockeye Salmon Populations Effect of Low Flow on Transportation of Adult Sockeye Effects of High Water Temperatures on Migrating Adult Sockeye Observed High Water Temperatures and Sockeye Mortalities Predicted Effect of Kemano I1 on Water Temperatures Measurement of Physical Data Method of Calculated Water Temperatures Predicted Water Temperatures for Extreme Weather Conditions Cooling Water Discharge Required for Temperature Control Predicted Effect of Kemano I1 on Dissolved Gas Concentration Volume of Water Required for Transportation Flow Possible Downstream Effects of Flow Diversion Conclusions Literature Cited Appendis . , . Tables A-1 to A-11, Figures A-1 to A-18 LIST OF TABLES

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Table 1. Timing of adult sockeye migrations in 5 Nechako River.

Table 2. Sockeye salmon spawning populations in 6 Nechako River tributaries.

Table 3. Annual commercial catch of sockeye 7 produced from Nechako River tributaries.

Table 4. Annual Indian food fishery catch of sockeye produced from Nechako River tributaries.

Table 5. Monthly mean air temperatures at Fort 19 St. James, in OF.

Table 6. Mean monthly maximum air temperatures 20 at Fort St. James, in 0 F.

Table 7. Maximum air temperatures at Fort St. 2 1 James, in 0 F.

Table 8. Highest mean daily water temperature in 22 Nechako and Stuart Rivers at their confluence, July 20 to August 31, and frequency of temperatures higher than 68'5' and 70'~.

Table 9. Difference between mean daily water temperatures in Nechako and Stuart Rivers at their confluence.

Table 10. Success of spawning of Early Stuart sockeye.

Table 11. Success of spawning of Early Nadina sockeye for years when mean daily temperatures in Nechako River were above 70'~.

Table 12. Nechako River and tributary discharge stations operated by Inland Waters Directorate, Department of Environment. LIST OF TABLES (Cont'd)

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Table 13. Average discharges of Nechako, Nautley 34 and Stuart Rivers for July, August and September, in cfs.

Table 14. Mean daily discharges at Skins Lake spillway for July, August and September, 1974 and 1975, in cfs.

Table 15. Mean daily discharges of Nechako River above Twin Creek near Irvines for July, August and September, 1974, in cfs.

Table 16. Mean daily discharges of Nechako River below Greer Creek for July, August and September, 1974, in cfs.

Table 17. Mean daily discharges of Nechako River at Fort Fraser for July, August and September, 1974 and 1975, in cfs.

Table 18. Mean daily discharges of Nautley River for July, August and September, 1974 and 1975, in cfs.

Table 19. Mean daily discharges of Nechako River 40 at Vanderhoof for July, August and September, 1974 and 1975, in cfs.

Table 20. Mean daily discharges of Stuart River 41 near Fort St. James for July, August and September, 1974 and 1975, in cfs.

Table 21. Water temperature recording stations 42 in the study area.

Table 22. Summary of physical data for Nechako 50 River at selected discharges.

Table 23. Comparison of measured and calculated 56 hourly temperatures for different solar radiation coefficients. LIST OF TABLES (Cont'd)

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Table 24. Mean difference between measured and 58 calculated temperatures.

Table 25. Travel time of Nechako River in hours, 59 Cheslatta-to-Nautley and Nautley-to- Stuart reaches.

Table 26. Computed temperatures of Nechako 61 River above Stuart for 1974 weather conditions and assumed river flows at Cheslatta compared to recorded temperatures for the actual discharge.

Table 27. Temperatures and discharges in Nechako 62 River for the days of highest mean daily water temperature in 1951, 1971, 1974 and 1975.

Table 28. Maximum air temperatures at Vanderhoof, 63 in 0 F.

Table 29. Comparison of calculated and measured 65 mean daily water temperatures of Nechako River above Stuart River in 1971, using simulated extreme weather data.

Table 30. Bathythermograph readings in Nechako 72 reservoir near Kenney Dam, in 0 F.

Table 31. Oxygen and nitrogen concentrations in 74 Nechako reservoir near Kenney Dam.

Table 32. Oxygen and nitrogen concentrations in 75 the upper Nechako River on August 22, 1974.

Table 33. Oxygen and nitrogen concentrations in 76 the lower Nechako, Nautley and Stuart Rivers on August 12-14, 1975.

Table 34. Calculated values of reaeration 77 coefficient in the upper Nechako River. LIST OF TABLES (Cont'd)

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Table 35. Calculated concentration of 77 dissolved oxygen and nitrogen in Nechako River above Stuart with only Nautley River inflow and assumed near extreme weather and initial saturation levels.

Table 36. Calculated nitrogen and oxygen 7 8 concentration at maximum daily water temperature in a cooling water flow of 4,500 cfs at 45'~from Nechako reservoir under near-extreme weather conditions.

Table 37. Calculated nitrogen and oxygen 79 concentration at maximum daily water temperature in a cooling water flow of 4,500 cfs of 45'~from Nechako reservoir under near-extreme weather conditions with aeration at point of release to equilibrate with air.

Table 38. Minimum daily discharge of Nautley 82 River from July 20 to September 30, for 1950 to 1975, in cfs.

Table 39. Quantity of water in acre-feet required 83 to maintain 1,000 cfs in the Nechako River below Nautley in the period July 20 to September 30, assuming no inflow from the upper Nechako. LIST OF FIGURES

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Figure 1. Nechako River watershed, showing the 2 existing hydroelectric diversion to Kemano .

Figure 2. Temperature of Stuart River at the 26 confluence with the Nechako from July 10 to August 31, and numbers of sockeye taken in the Indian food fishery at Fort St. James 2 days later.

Figure 3. Temperature of Nechako River above the Stuart confluence from July 20 to August 31, and numbers of sockeye taken in the Indian food fishery at Nautley River 2 days later.

Figure 4. Nechako River temperature study area. 3 2

Figure 5. Mean daily water temperature, Nechako River at Fort Fraser, 1950-58 and 1974-75.

Figure 6. Mean daily water temperature, Nechako 44 River above Stuart, 1950-75.

Figure 7. Mean daily water temperature, Nautley 46 River, 1950-75.

Figure 8. Mean daily water temperature, Stuart 4 7 River above Nechako, 1950-51, 1953-75.

Figure 9. Hourly water temperatures of Nechako 5 7 River above Stuart in the test period August 11-14 and September 3, 1975.

Figure 10. Effect of release of cooling water 6 7 from Nechako reservoir on temperatures of the Nechako River above Stuart, July 31, 1960.

Figure 11. Effect of release of cooling water 68 from Nechako reservoir on temperatures of the Nechako River above Stuart, July 31, 1971. INTRODUCTION

The B. C. Energy Board (1972) has recommended a second stage of development of the Nechako-Kemano project. The Kemano I project ylas built by the Aluminum Company of Canada and produced irs first power in 1957. The water supply for the existing Kemat~o plant comes from impoundment of the natural drainage in the Upper Nechako River basin now stored behind Kenney Dam constructed on the Upper Nechako River at Grand Canyon. From October 1952 until June 1955 no water entered the Nechako River from above the dam. Controlled flows of up to 600 cfs from Cheslatta Lake provided transportation water for salmon migr'ition, spawning and incubation downstream from the dam. In 1956 the first spill from Nechako reservoir was released through rhe Skins Lake spillway and routed down the Cheslatta system. The 1956 spills were intermittent and small and were partly detained in Cheslatta Lake for build-up of its natural storage. In January, 1957, the Nechako reservoir reached its maximum design elevation and since that time larger flows have been released from the Skins Lake spillway. Figure 1 shows the Nechako River watershed and the Kemano 1 development

The Kemano 11 project would require an additional tunnel through the Coast Range to divert a greater portion of the flow of Nechako River above Kenney Dam. The proposed additional diversion would result in greatly reduced flows in the Nechako River, which ~~ouldcorrespond to the conditions previously examined by the International Pacific Salmon Fisheries Com- mission and the Canada Department of Fisheries (1951, 1952, 1953). These earlier studies concluded that protection of the sockeye runs to the Nechako K~versystem would require provision of cold ORT ST. JANES

SCALE - NILES

Figure 1. Nechako River watershed, showing the existing hydroelectric diversion to Kemano.

I I water from Nechako reservoir for control of water temperature in the residual Nechako River below Kenney Dam. The facilities needed for this purpose were not provided. The earlier studies also established a transportation flow requirement in the portion of Nechako River between the Nautley and Stuart Rivers.

Biological and physical data have been collected in the Nechako region since completion of Kenney Dam in 1952. In 1974 and 1975, British Columbia Hydro and Power Authority paid the costs of a field program for collection of additional data required for further investigation of changes in water temperatures and dissolved gas concentrations in the residual Nechako River. This report reviews biological as well as physical data now available and presents conclusions based on this review. NECHAKO RIVER SOCKEYE SALMON POPULATIONS

Sockeye salmon migrate up Nechako River from the Fraser River each year in the period July 10 to October 5 (Table I), en route to spawning grounds in the Stuart and Nautley River tributary systems. The number of spawners in the individual stocks is given in Table 2 for the period 1938 to 1975. The Early Stuart and Early Nadina runs are the first to move up the Nechako, followed by the Late Nadina, Late Stuart and Stellako in that order.

These stocks have produced a commercial catch averaging 798,000 sockeye annually in the period 1952 - 1972 (Table 3). The average catch is 20% of the average catch produced by all Fraser River sockeye stocks in the same period. The average catch of 798,000 sockeye annually would have a value of $3,320,000 annually to fishermen and $7,360,000 annually to processors at 1974 prices. The net economic value of these sockeye salmon was determined to be $5,022,000 (Sinclair, 1976).

It is estimated that the major lakes of the Stuart and Nautley River systems, in which sockeye are reared, are capable of producing an average catch of 5,500,000 sockeye annually. Approximately 42% of the expansion of existing Nechako system stocks to reach this level of production involves the Early Nadina and Early Stuart stocks, the remainder involving the Late Stuart stock. Two-thirds of the unutil.ized lake rearing capacity for sockeye in the entire Fraser River system is in the lakes of the Nautiey and Stuart River systems. The development of this capacity is considered an urgent priority by the Commission. Large C,. auu aJuu mo0

aJ NNN .rl Z rl a hhh D & &I 444 d rd rd 323 w n '7-9 4 z H 4-03 n U 4 4 4 4 m z a, a, UU bO M OO rj rd 333 +' clQ 444 cl e: u 4 m aJ 0 N W aJ 4NN .rl 4 a, hhh & u 444 rd rd 333 W Q ')'?'?

ai OO & 0 QJ G C3 0 0 h s .rl UUaJ a&u U&d surd crdo u>u .rl 3 3 a .d 0 &Urd ze:4 &V]Z .. TABLE 2. Sockeye Salmon Spawning Populations in Nechako River Tributaries

Stuart System Nadina River Stellako Total All Runs Year Early Late River Early Late

Uncha, Nithi, Ormonde, Endako (small tributaries of the Fraser- Francois system) included with early Nadina. Tagetochlain (tributary of Nadina River) included with Late Nadina. p = Some spawners wese present but not counted. - = No observations were made. TABLE 3. Annual Commercial Catch of Sockeye Produced from Nechako River Tributaries

Nadina River Stellako Stuart System Total Year Early Late River Early Late All Runs

*I952 8,097 108 146,128 151,461 1,300 307,094 **I953 168,747 89,858 151,599 867,057 1,133,915 2,411,176 $<*I954 11,167 4,232 750,794 198,094 30,427 994,714 **I955 6,745 558 319,944 137,985 48,557 513,789 **I956 5,759 296 150,257 65,289 9,939 231,540 **I957 141,239 129,680 132,839 289,625 997,608 1,690,991 "*I958 4,806 4,173 1,036,135 114,399 111,932 1,271,445 **I959 6,201 2,982 583,055 23,336 44,212 659,786 **I960 6,880 616 200,200 63,891 12,116 283,703 **I961 106,605 96,352 115,973 996,570 904,414 2,219,914 ""1962 1,359 3,067 187,543 75,185 31,570 298,724 **I963 5,067 8,593 370,408 8,648 3,432 396,148 **I964 11,018 619 119,599 33,482 6,046 170,764 **I965 27,772 80,768 110,352 225,473 525,558 969,923 **I966 549 10,272 464,550 55,923 40,786 572,080 **I967 21,173 42,578 624,427 75,337 11,953 775,468 ""1968 12,035 11,327 139,413 13,803 1,542 178,120 **I969 20,388 65,955 172,315 270,449 843,947 1,373,054 1970 265 25,155 287,624 27,526 76, 204 416,774 1971 24,121 110,059 504,875 180,549 6,138 825,742 1972 7,466 56,622 98,641 12,126 27,472 202,327

* Does not include Johnstone Strait catches or small troll catches in non-Convention Waters, which are areas not regulated by the Crwmission. ** Does not include small non-Convention troll catches.

Tagetochlain Creek included with Late Nadina. Nithi, Endako, TJncha and Ormonde included with Early Nadina. spawning channel developments in the Lower Nadina River (Francois Lake), Ankwill Creek (Takla Lake), Kazchek Creek (Trembleur Lake) and Tachie River (Stuart Lake) have been recommended by the Commission (1972). At present the Commission operates a spawning channel on Nadina River at the outlet of Nadina Lake to increase production of the Late Nadina run.

The Early Stuart run has shown dramatic improvement in recent years, primarily as a result of conservation measures implemented annually since 1967. The 1973 Early Stuart total run, estimated at 1,360,000 sockeye, was the largest since 1900 and very likely the largest ever to utilize the - system. This run grew in two cycles from an escapement of only 23,000 spawners in 1965 and illustrates the tremendous production capability of the race under favourable conditions.

The sockeye runs to the Nechako system are the source of a substantial Indian subsistence food fishery between Mission and Fraser Lake and Trembleur Lake. The average annual catch from the Nechako stocks has been 36,000 sockeye (Table 4), which is 31% of the total Indian food fishery catch for all Fraser River runs. Approximately 40% of the catch from the Nechako stocks is made from the Early Nadina and Early Stuart runs. These early runs are the first to move up the Fraser River each year and are of particular interest to the Indians. TABLE 4. Annual Indian Food Fishery Catch of Sockeye Produced from Nechako River Tributaries

Nadina River Stuart System S tellako Total Year Early Late River Early Late All Runs

1.95 2 424 6 6,770 6, 671 485 14,356 1953 3,008 1,602 4,747 27 ,427 24,207 60,991 1954 24 6 93 17,459 8,673 783 27,254 1955 20 8 17 13,101 1,357 2,415 17,098 1956 274 14 6,590 3,077 1,020 10,975 1957 3,574 3,282 4,361 23,954 22,544 57,715 1958 73 63 9,562 4,467 3,262 17,427 1959 189 91 8,142 519 463 9,404 1960 362 32 8,415 4,134 389 13,332 1961 3,281 2,948 8,020 30,181 44,87 7 89,307 1962 106 239 19,068 6,631 4,768 30,812 1963 688 1,155 21,939 1,669 411 25,862 1964 866 49 14,008 10,805 708 26,436 1965 849 2,446 8,531 7,807 32,546 52,479 1966 15 29 2 16,840 4,300 1,264 22,711 1967 462 1,653 15,105 3,142 295 20,657 1968 988 401 14,482 12,807 135 28,813 1969 916 2,946 10,448 52,816 37,895 105,021 1970 88 4,377 15,476 22,897 2,762 45,600 1971 1,483 5,823 10,127 49,662 472 67,567 1972 1,346 4,908 8,969 6,976 4,011 26,210 EFFECT OF LOW FLOWS ON TRANSPORTATION OF ADULT SOCKEYE

Impoundment by Kenney Dam of the Upper Nechako drainage above the Cheslatta confluence commenced on October 8, 1952 and resulted in extreme reduction in the Nechako River flow. In a few days the flow in the reach above Nautley was reduced from about 4,500 cfs to under 100 cfs and in the reach from Nautley to Stuart the flow changed from just over 5,000 cfs to about 600 cfs.

Filling of the reservoir behind Kenney Dam to maximum level continued until January, 1957. During the 1952-1957 period, flow in the Nautley-to-Stuart reach of Nechako River consisted mainly of the natural Nautley River flow augmented with Upper Nechako discharge from the Cheslatta system and minor tributary flows from below the Cheslatta confluence. The flow at Vanderhoof (Nautley-to- Stuart reach) during the period of sockeye migration varied from a low of 766 cfs to a high of 5,090 cfs from 1953 to 1956, inclusive. In the years 1954 and 1955, discharges in some periods consisted partly of controlled flow releases from temporary storage provided by Alcan on Cheslatta Lake for fisheries purposes and in 1956 minor flows were released from Nechako reservoir at Skins Lake.

Since January 1957, water not required for the existing development at Kemano has been released from the Nechako reservoir at Skins Lake. During yearly spring run- off, water from the Upper Nechako drainage basin has been retained in the reservoir to reduce the Nechako River contribution to peak discharge in the Fraser River. Spills were controlled for selected days during the summer nonths of 1974 as requested by the Environment Canada, Fisheries and Marine Service as part of the environmental study of the proposed Kemano expansion. The minimum and maximum discharges recorded at Vanderhoof since 1957 during July, August and September have been 1,560 and 19,600 cfs respectively.

Initial studies in 1951 of the problem of maintaining sufficient flow in the Nautley-to-Stuart reach to provide unimpeded upstream passage for sockeye concluded that a flow of 1,200 to 1,500 cfs would be needed. Examination of the river in October, 1952, after closure of Kenney Dam, disclosed that at flows of 600 to 800 cfs there were some areas of extremely shallow water which could make fish migration difficult and cause delay. Observations during salmon migration in August and September, 1953 indicated that adult sockeye migrated successfully in the Nautley-to- Stuart reach at discharges as low as 1,100 cfs. On the basis of these observations, it was recommended that the flow should not be less than 1,000 cfs during the sockeye migration period (Int. Pac. Salmon Fish. Comm. 1953).

With the existing Nechako diversion, the Nechako River discharge below Nautley River has been considerably higher than the estimated safe minimum for transportation of adult sockeye. As described in a later section, however, further flow reduction as described by the B. C. Energy Board (1972) for the Kemano I1 development would result in minimum flows far lower than required for safe migration of adult sockeye. EFFECTS OF HIGH WATER TEMPERATURES ON MIGRATING ADULT SOCKEYE

Previous studies of the effect of the proposed diversion on water temperature in the Nautley-to-Stuart reach concluded that the possibility of loss of adult sockeye as a result of high water temperature was great enough that steps should be taken to provide cold water to prevent such a loss (Int. Pac. Salmon Fish. Comm. 1953). Recommendations were made for the release of up to 70,000 acre-ft. of 40°F water at Kenney Dam from the Nechako reservoir to limit the mean daily water temperature in the Nechako River above the Stuart River to not more than 68'~.

The temperature limit of 68'~was the highest mean daily water temperature considered safe for adult sockeye migrating up the Nechako River (Int. Pac. Salmon Fish. Comm. and Can. Dept. Fish., 1951). This conclusion was reached on the basis of limited information available at that time but later investigations have provided additional reasons for concern about high water temperatures during the migration of adult sockeye.

Abnormally high water temperatures have been shown to be directly lethal to salmon. In studies of temperatures of 26'~ (78.8'~) and higher, Coutant (1969) found a median 0 0 survival time of approximately 200 minutes at 26 C (78.8 F) for jack coho and chinook salmon, decreasing as temperature increased.

Studies conducted by the Commission (1973) showed no mortalities of adult sockeye in 15 days of exposure to temperatures of 18'~ (64.4'~) and 21°c (69.8'~)~but these fish had been treated with tetracycline, Furanace and malachite green to protect them against bacteria and fungus. At a temperature of 25'~ (77.0'~) the time to 50% mortality was about 4 hours. Shorter survival times were observed for higher temperatures and at 30°C (86.0'~) the median survival time was 10 minutes. At 24OC (75. OF), 23'~ (73.4'~) and 22'~ (71.6OF), the time to 50% mortality was about 2, 2.5 and 5 days respectively. The fish exposed to these three temperatures showed evidence of columnaris infection. The survival time at 24'~ (75.2'~) is similar to that indicated from extrapolation of Coutant's data.

A temperature increase from 15'~ (59'~) to 0 25 C (77'~) caused a 53% increase in the metabolic rate of adult sockeye (Brett and Glass, 1973). Thus, at higher temperatures the body energy reserves would be utilized at a higher rate. This temperature effect, in conjunction with the additional energy required for migration up the Fraser River during high river discharge, could result in depletion of the energy stores before sockeye reach their spawning grounds. Brett (1965) concluded that energy expenditure of Stuart River sockeye was nearly 80% of the maximum rate they could maintain, leaving little margin for any emergency demand on the energy stores of the fish.

Stress resulting from elevated water temperature may produce indirect effects on salmon. Stress alters bio- chemical reactions and some of the resulting changes may contribute to increased susceptibility to infection. Fish pathogens or infectious organisms have been documented in the Praser River watershed and under diverse circumstances have contributed to significant mortalities in various systems, including the Early Stuart, Early Nadina, Stellako and Late Stuart runs (Int. Pac. Salmon Fish. Comm., 1962). The potential exists for infection of a population that has been subjected to abnormal stress, whether the result of high water temperature, delays or unusual exertion during the migration to the spawning grounds. Paralysis of the reticuloendothelial system, increase in the proteolytic power of the plasma and alterations in steroid hormone meta- bolism are some of the significant effects exerted by stress- ful environmental changes, which can be ultimately responsible for potentiating microbial infectious processes (Wedemeyer, 1970).

Increasing water temperature can result in supersaturation of dissolved gasses unless there is sufficient turbulence and exchange of gas to the atmosphere to offset the lower solubility at increased temperature. Supersatura- tion of dissolved gasses at high levels can result in mortality of salmon and at sublethal levels the fish can be stressed with subsequent indirect mortality. The pathology has been reviewed by Stroud et al. (1975) and Harvey (1975). The effects are attributed to the total dissolved gas pressure. In supersaturated waters nitrogen occurs in the gas bubbles in about the same proportion as in the air. Nebeker et. al. (1976) tested adult sockeye at 120%, 115% and 110% gas saturation. Mortality occurred in 77 hours at 120% and in 523 hours at 115%, but no mortality occurred at 110%. The survivors of fish exposed to 120% and 115% gas saturation showed gill damage and hemorrhaging, with bubbles in the mouth, on gill arches, body surface and fins. The mortalities at 115% saturation were attributed to diseases resulting from stress caused by exposure to supersaturation. Stroud and Nebeker(l975) also tested juvenile steelhead trout at the same supersaturation levels as above. A 50% mortality occured in 54 hours at 120%, but no mortality occurred at 115% in 336 hours or at 110% in 408 hours. A variety of external lesions occurred at 115% and 110% and it was observed that exposure to sublethal levels may also cause decreased peristaltic movement of the gastro intestinal tract leading to subsequent bacterial invasion. Nebeker and Brett (1974) exposed juvenile sockeye to supersaturation conditions for 48 days. A 50% mortality occurred in 40 hours at 120% saturation and 400 hours at 115%, but there was no mortality at 110%. Severe emphysema occurred at 120% and 115%. Emphysema was not as severe at 110% but occurred in 20% of the sockeye.

Embolism has been observed in some sockeye below McNary Dam on the Columbia River when nitrogen saturation ranged from above 110% to above 120% (Ebel, 1970). Eye injuries and blindness in chinook salmon have been associated with 108 to 124% nitrogen saturation (Chambers, 1963, Meekin and Moser, 1966, Allen and Moser, 1967). Mortalities of chinook salmon occurred in 24-hour exposure to 134% nitrogen saturation (Snyder and Blahrn, 1971). On the Columbia River, there is concern that the effects of supersaturation and increasing water temperature may be synergistic (Harvey, 1975). In Water Quality Criteria (1972) it is recommended that, for protection of aquatic life, total dissolved gas pressure in water should not exceed 110% of saturation, and any prolonged artificial increase in total gas pressure should be avoided in view of the incomplete body of information. Temperature may also affect behavior of salmon, causing a block in migration. A lengthy delay of adult chinook salmon and steelhead trout occurred in the Columbia River at the mouth of the Snake River in 1967 when the Snake 0 River was 71 to 7g°F, or about 7 to 8' warmer than the Columbia River. The delay ended when the temperature dif- 0 ference decreased to 3 F, with the Snake River temperature of 72'~ (Snyder and Blahm, 1971). A delay of sockeye migrating in Nechako River could deplete the energy reserves of the fish to such an extent that they would not be able to complete migration and spawning.

The previously specified temperature level of 0 68 F may provide a margin of safety but it is impossible to determine whether this margin would provide adequate protection for all of the fish in all years because the severity of the imposed stresses varies from year to year. The virulence of disease organisms is known to vary over wide limits. In a study of thermal pollution, the Federal Water Pollution Control Administration (1968) made a pro- visional recommendation for 680 F as the maximum temperature compatible with well-being of salmonids on their migration route. OBSERVED HIGH WATER TEMPERATURES AND SOCKEYE MORTALITIES

Observations of dying and dead sockeye in Nechako River and Fraser River between Prince George and Quesnel in 1942 (Int. Pac. Salmon Fish. Comm., 1942) were the first known record of sockeye mortalities associated with high water temperature. Water temperatures were not measured on a continuous 0 basis at that time but spot temperatures up to 72.5 F were measured. Air temperature records at Fort St. James (Environ- ment Canada) show that mean air temperatures in July and August of 1942 were above average but have been equalled or exceeded 13 times in July in 77 years and 18 times in August in 78 years of record (Table 5). Similarly, the mean maximum air temperatures were above average in 1942 (Table 6) but have been equalled or exceeded 9 times in July in 77 years and 26 times in August in 78 years of record. Therefore, it is reasonable to expect that water temperatures equal to or exceeding those in 1942 would occur even with the Nechako River unaltered from its natural flows.

Maximum air temperatures at Fort St. James in 1941 were the highest ever recorded in July in 77 years (Table 7). Few sockeye reached the Nechako system in 1941 because of the obstruction at Hell's Gate. However, sockeye were observed resting in Bednesti Creek, which flows into the Nechako about 20 miles upstream from Prince George and they were seen there in 1942 also. Since there is no sockeye run native to Bednesti Creek, these observations show that the sockeye were under stress. No data are available concerning sockeye runs in earlier years of indicated high temperature. Records of water temperature obtained since 1950 in Nechako and Stuart Rivers above their confluence show 0 frequent occurrence of temperatures greater than 68 F in the period July 20 to August 31 (Table 8). The highest recorded temperatures occurred at the end of July, 1971 during a period of low discharge and high air temperatures. On 0 July 31, the mean daily temperature of 77.3 F in Nechako River was 6.5O~higher than in Stuart River (Table 9). This difference is greater than observed in other years at lower Nechako discharges. In contrast, in years of high Nechako River discharge such as 1958, 1961 and 1968, the daily mean 0 temperatures in the Nechako River were 2.5, 3.8 and 3.0 F respectively cooler than in Stuart River, illustrating the modifying effect of high river discharges.

The effects of high temperature on sockeye in Nechako and Stuart Rivers are likely to be quite variable because of the diverse conditions encountered by sockeye runs in different years during migration from the mouth of the Fraser River to the spawning grounds. Sockeye that arrive in Nechako River in good condition may not be affected as much by high water temperatures as sockeye that have been subjected to severe stresses during their migration.

During the period from 1952 to 1975, the Nechako and Stuart Rivers have been surveyed periodically by staff of the Fisheries Service, the Commission, and the Aluminum Company of Canada. Alcan staff have observed the sockeye migrations in the Stuart River and at Fort St. James from 1952 to 1971 and reported no dead or distressed sockeye. They also inspected Nechako River between Nautley and Stuart Rivers frequently in the summer months from 1952 to 1958 TABLE 5. Monthly Mean Air Temperatures at Fort. St. James, in OF

-Year July August Year July August

1932 55.5 60.3 1972 56.9 58.4 1933 56.2 59.7 1973 58.4 55.5 1934 57.7 57.8 1974 55.0 59.3 1935 59.7 55.0 1975 61.5 53.8 1936 56.9 57.2 AVERAGE 57.3 -- 55.7 TABLE 6. Mean Monthly Maximum Air Temperatures at Fort St. James, in OF

-Year- July August -Year July August

1932 69.1 73.1 1972 68.5 70.5 1933 69.6 75.8 197 3 71.5 68.7 1934 70.6 72.0 1974 66.8 72.7 1935 73.0 69.4 1975 73.7 63.1 1936 70.8 72.0 AVERAGE 71.1 69.6 TABLE 7. Maximum Air Temperatures at Fort St. James, in 0 F

Year July August Year July August

1932 79.0 84.0 1972 79.0 82.0 1933 80. 0 92.0 1973 86.0 87.0 1934 88.0 85. 0 1974 83.0 83.0 1935 88.0 80.0 1975 88.0 78.0 1936 80.0 82.0 AVERAGE 85.1 82.5 TABLE 8. Highest Mean Daily Water Temperature in Nechako and Stuart Rivers at Their Confluence, July 20 to August 31, and Frequency of Temperatures Higher than 68'~and 70'~

NECHAKO RIVER STUART RIVER Year Date No. days above Date No. days above 0 OF 68' 70' F 68' 70'

1950 Aug. 23 67.8 0 0 Aug. 25 67.8 0 0 1951 3 68.4 1 0 3 67.5 0 0 1952 4 67.8 0 0 - - - 1953" 6 70.3 4 1 5 66.3 0 0 1954* 6 67.8 0 0 7 64.5 0 0 1955* July 23 70.3 4 1 July 23 66.5 0 0 1956* 20 73.8 14 5 20 71.4 4 2 1957 20 66.5 0 0 Aug. 10 63.3 0 0 1958 20 68.5 4 0 July 20 70.3 7 1 1959 23 69.0 5 0 23 69.0 4 0 1960 Aug. 1 71.0 12 7 Aug. 2 70.3 9 3 1961 4 67.3 0 0 5 70.5 17 2 1962 1 69.5 2 0 July 31 69.7 5 0 1963 10 66.5 0 0 Aug. 9 67.5 0 0 1964 20 61.0 0 0 12 61.0 0 0 1965 21 68.5 3 0 5 69.5 7 0 196 6 25 63.0 0 0 25 63.5 0 0 1967 18 67.3 0 0 18 68.5 1 0 1968 3 66.0 0 0 4 67.3 0 0 1969 July 20 65.5 0 0 July20 64.3 0 0 1970 Aug. 4 70.5 5 3 Aug. 5 66.7 0 0 1971 July30, 77.3 27 24 July28 72.0 21 10 31 1972 Aug. 8 66.0 0 0 Aug. 8 67.2 0 0 1973 1 67.8 0 0 2 66.5 0 0 1974 19 67.3 0 0 4 63.8 0 0 1975 July 24 66.0 0 0 July 24 67.5 0 0

* Reservoir filling from October, 1952 to January, 1957. and no dead fish were seen, with the exception of 50 un- spawned sockeye reported in mid-September, 1954. Occasional observations were made from 1959 to 1974 and no dead fish were reported.

The Commission staff recovered approximatel-y 1,500 un- spawned sockeye carcasses in the Nautley-to-Stuart reach in mid-September, 1954 at water temperatures of 58 0 to hl0F. These fish were from the Stellako run. About ten carcasses were also found in mid-September, 1955, in temperatures of 54.5 to 56.5'~. No carcasses were seen in either the Nechako or Stuart Rivers in 1957, 1958, 1962, 1963 or 1969. Frequent examinations were made at several locations in 1974 and one sockeye carcass was found on September 5, when the mean daily water temperature was about 62.8 0 F. Dead sockeye were observed in Stuart Lake in 1965 and in 1975, and in Stuart River immediately above the Nechako confluence in 1975 in water temperatures of 67.5'~ and lower.

In the Stuart River, temperatures higher than 70°F at the confluence with the Nechako occurred in 1956, 1958, 1960, 1961 and 1971. Success of spawning of the Early Stuart sockeye (Table 10) was good in 1956 and 1958, but there were losses of 16, 29 and 15% respectively in 1960, 1961 and 1971. There is no record of any observation of distressed or dying Early Stuart sockeye in the Nechako or Stuart Rivers or Stuart Lake in any of these years. TABLE 9. Difference Between Mean Daily Water Temperatures in Nechako and Stuart Rivers at Their Confluence at Various Discharges

Nechako Mean Nechako Discharge Less Stuart Mean At Vanderhoof Year Date 0 F cfs

LOW DISCHARGE

1953 Aug. 6 6.5 2,520

1954 July 26 4.5 2,930

1955 Aug. 6 4.4 1,820

1956 Aug. 22 4.2 928

1957 July 20 6.3 3,610

197 0 Aug. 8 4.5 3,670

1971 July 31 6.5 6,270

1975 July 3 3.0 4,510

HIGH DISCHARGE

1958 Aug. 30 - 2.5 10,300

1961 Aug. 5 - 3.8 13,700

1968 July 22 - 3.0 15,700 TABLE 10. Success of Spawning of Early Stuart Sockeye

Percent Success Year Of Spawning

Examination of abundance of Early Stuart sockeye, as indicated by Indian food fishery catches at Fort St. James, in relation to daily water temperatures 2 days earlier at the lower end of Stuart River (Figure 2) shows that in each of these years the abundance of sockeye was low during periods when the mean daily temperature exceeded 700 F. In 1971, sockeye must have been abundant in the lower Stuart River on July 24 and 25, when the daily mean temperature was about 69.5'~. A few sockeye apparently migrated through this 0 portion of the river on July 28 in a mean temperature of 72 F. Because 15% prespawning mortality was observed, and because this loss was associated with the latter part of the run rather than the usual case where losses occur amongst the early arriving fish, some adverse effect of these high temperatures is indicated.

In the Nechako River, temperatures higher than 70'~at the confluence with the Stuart occurred in 1953, 1955, 1956, 1960, 1970 and 1971. Success of spawning of the Early Nadina run was high in all of these years (Table ll), and there are no records of observations of distressed or dying sockeye. However, examination of the abundance of Early Nadina I

0 I

h V) C 0 O 0 0 .I

Y I x V) 9 Ir,

- . ..!> a W m I r 3z

0 10 20 3 1 10 20 3 1 J U LY AUGUST

Figure 2. Temperature af Stuart River at the confluence with the Nechako from July 10 to August 31, and numbers of sockeye taken in the Indian food fishery at Fort St. James 2 days later. sockeye, as indicated by Indian food fishery catches at Fraser Lake, shows that in each year except 1971 there were few sockeye present during periods when the mean daily 0 temperature exceeded 70 F (Figure 3). Reports of dead fish in the Nechako River between Vanderhoof and the Stuart confluence were received on August 2, 1971, two days after the peak temperatures. During a survey on August 4, dead suckers, chub, squawfish and whitefish were observed in shallow shoreline areas, but no dead salmon were seen (Tuyttens, 1974).

TABLE 11. Success of Spawning of Early Nadina Sockeye for Years when Mean Daily Temperatures in Nechako River were above 700 F

Percent Success Number Year Of Spawning Of Spawners

Very few fish migrated up Nautley River prior to August 5, 1971, although the first fish of the Nithi run passed Nautley on July 28. The majority of the Early Nadina and the Nithi sockeye moved up Nautley River after August 12. The first sockeye arrived in the Lower Nadina River about August 18, indicating late timing of the run, similar to that in 1955 and 1959, but about 2 weeks later than observed in 1953, 1961, 1963, 1965 and 1967. The first arrivals of the Nithi run in 1971 had very high prespawning mortality, whereas the first arrivals at Nadina did not, possibly indicating the Nithi fish may have been stressed by conditions not encountered by the Early Nadina fish. The group of sockeye passing Nautley on August 13 probably passed through the Nechako above Stuart on August 11 in a mean daily temperature of 73'~.

In view of experimental evidence concerning the 0 adverse effects of temperatures higher than 70 F, it is concluded that fish migrating up the Nechako River when mean daily temperatures exceeded this level were able to complete the 2-day migration during morning and early afternoon hours 0 when temperatures were less than 70 F and were able to avoid or survive the short periods of higher temperatures. During the 2-day upstream migration, temperatures in the second day would be lower than just above the Stuart confluence. Such a tenuous means of survival may not have serious effects on a very small population with minimal stress from competition, but such conditions cannot be regarded as acceptable for large populations.

The relatively small number of sockeye mortalities in Nechako River in years of high temperatures appears to have resulted from fortuitous timing and/or low abundance of sockeye runs at the time of occurrence of high temperatures. The late timing of the 1971 Early Nadina run may also have reduced the mortality rate since it has been observed with other sockeye runs that late-timed runs are less susceptible to prespawning mortality (Int. Pac. Salmon Fish. Comm., 1974) If the 1971 Early Nadina run had migrated two weeks earlier, as often occurs, it probably would have encountered the highest recorded temperatures in the Nechako River, and there would have been substantial losses of fish. Field observations concerning the effects of high temperatures on sockeye in the Nechako and Stuart Rivers do not define the maximum temperature permissible. In view of the rapidly increasing risk at temperatures above 700 F, as indicated by the experimental data, a temperature limit of 0 70 F could not be considered as a safe limit on a continuing basis during every spawning migration. It is therefore concluded that the safe objective would be to ensure that temperatures in the Nechako River do not exceed a daily mean of 68'~. PREDICTED EFFECT OF KEMANO I1 ON WATER TEMPERATURES

The effects of the proposed Kemano I1 development on Nechako River water temperatures have been analyzed using data collected during the summers of 1974 and 1975 and, where applicable, data collected for previous studies. Measured temperature changes in the existing Nechako River were compared with changes calculated by energy-budget formulae. From this comparison, adjustments to the formulae were made to account for the effects of variables for which data were not available. The revised formulae were then used to predict changes in water temperature for the reduced river discharges that would occur with the Kemano I1 development. The locations of various data collection sites are shown in Figure 4.

Measurement of Physical Data

Stream flow records for July, August and September for stations on Nechako River and tributary streams are listed in Table 12.

TABLE 12. Nechako River and Tributary Discharge Stations Operated by Inland Waters Directorate, Department of Environment Location Station No. Years of Operation

Nechako River at Fort Fraser Nechako River at Vanderhoof Nechako River at Isle Pierre Stellako River at Glenannan Nautley River near Fort Fraser Stuart River near Fort St. James 08JE001 1929-1975 SCALE-MILES

Figure 4. Kechako River temperature study area Flow releases from Nechako reservoir at the Skins Lake spillway are routed through Cheslatta Lake and River system, entering the Upper Nechako River at Cheslatta Falls. These flow releases have been recorded by Alcan since 1955.

Table 13 summarizes the average discharges for the months of .lulj., August and September for Nechako River at Vanderho~f,Nautley River and Stuart River for the period prior to completion of the Alcan diversion in October, 1952, the period 1953 - 1956 when only minor tributary flows and intermittent flow releases were recorded in the Upper Nechako River, and the period 1957 - 1975. In January, 1957, the Nechako reserT~oirreached its maximum elevation and since that time larger flows have been released from the Skins Lake ~pillw~iy.

The mean daily discharg~sfsr the months of July, August and September for Nechako, Nautley, and Stuart Rivers and flaw releases at Skins Lake spillway for the study perio.1 in 1974 and 1975 are listed in 'Tables 14 - LO, inclusive.

Water temperatures have been measured during the summer months at vari~)!:s locations in the Nechako River and tributary streams sincc 1950. Weekly automatic recorders were generally used at al.1 stations. Tahle 21 lists these temperature stations, years -,f nperation covering the months of July, AUS~ISt and Septemhrr ar;d operating agency.

TABLE 14. Mean Daily Discharges at Skins Lake Spillway for July, August and September, 1974 and 1975, in cfs.(~_'~~i.~~~- 1974 1975 ment I Canada) Day I July August septemberI July August September ( TABLE 15. Mean Daily Discharges of Nechako River above Twin Creek near Irvines for July, August and September,

1976,.- in cfs.- -. 1974 Day July August Septem'ber

1 7,020 1,130 2 7,050 1,070 3 7,120 1,020 4 37 0 7,200 990 5 360 7,250 960 6 350 7,220 970 7 34 0 7,250 950 8 33 5 7,250 950 9 330 7,250 950 10 370 6,920 960 11 620 6,700 960 12 1,200 6,010 97 0 13 1,920 5,300 960 14 2,450 4,700 95 0 15 3,200 4,150 940 16 3,700 3,790 930 17 4,140 3,380 910 18 4,600 3,030 910 19 5,050 2,760 910 20 5,550 2,550 21 5,680 2,320 22 5,900 2,120 23 6,180 1,990 24 6,350 1,840 25 6,550 1,710 26 6, 620 1,600 27 6,700 1,510 28 6,760 1,420 29 6,850 1,31.0 30 6,920 1,250 31 7, 01.0 1,190 TABLE 16. Mean Daily Discharges of Nechako River below Greer Creek for July, August and September, 1974, in cfs. I 1974

Day July August September TABLE 17. Mean Daily Discharges of Nechako River at Fort

Fraser for July, August- and September, 1974 and and 1975, in cfs. 1974 1 1975 Day July August September July August September 1 7,330 1,240 2,550 5,620 - 2 7,320 1,200 2,550 5,730 3 7,400 1,020 2,550 5,810 4 740 7,450 1,000 2,550 5,510 5 740 7,420 990 2,580 4,850 6 740 7,410 1,000 2,600 4,190 7 740 7,410 1,020 2,640 3,760 8 740 7,410 1,030 2,650 - 9 7 40 7,410 1,040 2,640 2,740 10 740 7,410 1,020 2,700 2,590 11 1,045 7,410 99 0 2,700 2,550 12 1,350 7,240 960 2,700 2,590 13 1,860 6,050 990 2,650 2,650 14 2,400 5,350 1,000 2,660 2,650 15 2,890 4,700 1,040 2,700 2,740 16 3,410 4,100 990 2,580 2,820 2,750 17 3,880 3,450 990 2,580 3,210 2,750 18 4,450 3,000 940 2,550 3,500 2,700 19 4,950 2,700 990 2,560 3,780 2,660 2 0 5,400 2,400 2,540 4,190 21 5,690 2,220 2,550 4,350 22 6,000 2,050 2,550 4,500 23 6, 250 1,920 2,550 4,700 2 4 6,550 1,780 2,550 4,800 25 6,720 1,720 2,550 4,990 2 0 6,850 1,570 2,540 5,100 27 6,980 1,410 2,540 5,110 28 7,080 1,340 2,540 5,400 29 7,210 1,330 2,520 5,410 30 7,300 1,330 2,500 5,510 31 7,320 1,310 2,510 5,530 TABLE 18. Mean Daily Discharges- of Nautley River for July, August and September, 1974 and 1975, in cfs.(Envi onment 1974 I 1975 Canada) Day I July August September] July August September TABLE 19. Mean Daily Discharges of Nechako River at Vanderhoof for July, August and September, 1974 and 1975, in cfs. (Environment Canada) - ..~. 1974 1975 Day July August September July August September 1 4,220 9,620 2,120 5,040 4,480 7,330 2 4,140 9,650 2,030 5,080 4,490 7,350 3 3,860 9,650 2,000 5,030 4,510 7,390 4 3,870 9,690 1,990 4,920 4,520 7,420 5 3,860 9,710 1,970 4,920 4,540 7,280 6 3,770 9,670 1,960 4,960 4,530 6,630 7 3, 650 9,650 1,950 5,000 4,520 5,820 8 3,620 9,640 1,950 4,820 4,490 5,430 9 3,590 9,580 1,930 5,010 4,490 5,130 10 3,610 9,550 1,940 4,810 4,600 4,690 11 3,720 9,580 1,940 4,840 4,600 4,400 12 4,050 9,400 1,900 4,840 4,570 4,320 13 4,560 8,590 1,860 4,770 4,560 4,340 14 4,820 7,910 1,830 4,740 4,580 4,370 15 5,150 7,170 1,820 4,750 4,670 4,410 16 5,430 6,260 1,810 4,740 4,780 4,430 17 6,240 5,670 1,790 4,700 4,950 4,460 18 6,760 5,090 1,780 4,650 5,180 4,480 19 7,200 4,580 1,770 4,630 5,410 4,440 20 7,830 4,250 1,740 4,630 5,630 4,400 21 8,130 3,980 1,730 4,590 5,850 4,380 22 8,420 3,680 1,700 4,570 6,020 4,330 23 8,770 3,430 1,700 4,540 6,210 4,310 24 8,810 3, 240 1,690 4,540 6,420 4,300 25 9,060 3,060 1,680 4,530 6,510 4,290 26 9,170 2,900 1,700 4,510 6,640 4,250 27 9,280 2,780 1,690 4,530 6,770 4,240 28 9,380 2,660 1,670 4,550 6,990 4,230 29 9,470 2,550 1,650 4,530 7,110 4,240 30 9,580 2,420 1,560 4,510 7,190 4,240 31 9,620 2,230 4,490 7,250 * - TABLE 20. Mean Daily Discharges of Stuart River near Fort St. James for July, August and September, 1974 and 1975, in cfs. (Environment Canada) 1974 July August September July August September TABLE 21. Water Temperature Recording Stations in the Study Area

Years of Operation Location July-September Agency

Nechako River at Fort Fraser 1950-58, 1974, 1975 IPSFC

Nechako River 1950 IPSFC below Nautley 1959- Alcan

Nechako River IPSFC above Stuart Alcan

Necbako River IPSFC below Stuart Alcan

Nechako River at Prince George 1945, 1953-54, 1958-59, 1974 IPSFC

Nautley River 1950-58, 1974, 1975 IPSFC 1959- Alcan

Stuart River 1950-51, 1953-65, 1974, 1975 IPSFC above Nechako 1953- Alcan

Nechako River IPSFC below Cheslatta 1974 Alcan

Nechako River below Greer Creek 197 4 IPSFC

Nechako River at Vanderhoof 1974, 1975 IPSFC

Mean daily water temperatures for the period July, August and September for the years of records are shown for Nechako River at Fort Fraser and above Stuart, Nautley River and Stuart River in Figures 5-8, inclusive.

The mean daily temperatures for the stations operated in 1974 and 1975 are given in Table A-1. These data were obtained with Taylor Model 76JM217 thermographs. Water temperatures were also measured at 15-minute intervals with hand thermometers on selected days at various Nechako River locations during the 1974 and 1975 study periods These data are listed in Table A-2.

The meteorological factors affecting stream temperature changes include solar and atmospheric radiation, air temperature, air vapor pressure, atmospheric pressure, wind speed, amount of cloud cover and precipitation. Since these meteorological factors vary with time and location, a central weather station was established at Fort Fraser and a mobile weather station was operated at various locations along the upper and lower reaches of Nechako River. At the fixed weather station, necessary meteorological measurements were recorded daily on a 24-hour basis. The mobile station was operated only during daylight hours on selected clear days. The following instruments were used at each weather station:

Weather Measure Corporation Model R401E mechanical pyranograph Casella Model T9154 thermohygrograph Taylor Model AM5000 anemometer Taylor Model 6410 aneroid barometer Taylor Model 76JM217 thermograph

Table A-3 summarizes the data collected at the Fort Fraser station and the mobile weather station during the summers of 1974 and 1975. Barometric pressure, wind velocity and cloud cover were measured several times each day, as indicated, and values for intermediate hours were interpolated. The other data were recorded on charts from which hourly values were read.

The Nechako River was divided for study purposes into the Upper and Lower reach above. and below Na~tley5.ivcr confluence. The present Upper Nechako River reach rxt ends fron the lower end of the Grand Canyon where Cheslatra River enters Nechakc~River and dowc to the Nautley River conflxence, The Nechako RiT3er above the Cheslatta confluence was left dry after the closure of Kenney Dam in 1952 and all spills from the Nechako reservoir have since been routed dawn thi Cheslatta system. The upper reach from Chesiatta to tiautley is approxirnate.i;y 56 miles long.

The Lower Xechako reach extends fsoni tht? NstiC.l.ey

down L:, Prince (;ear-ge, where the Nechako jc,il;s rhe Frasr.1. River. Or:ly thi real:-!; from Nautley to the Stur;rt !liver confil~e~cs,a distance of about 60 mil.es, has Seen inc!.~ied in che pr~sdntwnt;er tenperature prediction st-dy.

The inport.an: str~:smcharacteristics -;:t,~:ctirig,- ? watc..i- ternp4?ratura changes inc:lude stagc/dischar;ie. ;-elaclij:~- . . ~,:.i1~~C~L::;S--SF!C t 20riij .3rea, surface width, turf::il.e:ic e, turbidity, temperature of surrounding iand and the r?xcjilr:c cf shade from vegetation and adjacent stream bank.s. f'i;.id

surveys were carried out in the Upper Nechako rear5 dtir;"1--i LC& rhe surnmsr of 1471, to measure t;ir required streaiil ci~ac~c::eristic.s,

Discharge measurement s~ationswere established abi;ve. !.'wi..rl Crcek, bel~wGreer Creek and at. Fort Praser, approxii!iateiy 6 miles, 21 miles 2nd 51 mil.es respecti.vely d~wnstrea~i:L-cm the ihesldtta i:cnflufnce. The stage/disch;,~rge3,ca fcr s;ch of these stations is shown in Figures A-1, A-2 and A-3,

In addition, 55 stations Pn the reach between Che~latraand Nautley verc established at approximately

il~:~:-~::ilc i~ltervals. At each .~fthese st,^ tiu;:s :he :;:ream was cross sectioned by means of depth sounder on a boat and/or by surveying with a rod, chain and transit. The bank slopes were also determined at each cross section. A staff gauge for referencing water surface elevations was established at each station and this gauge was recorded at least 3 times throughout the summer at low, intermediate and high flows. From these survey data, mean stream depth and mean water travel time for each of the reaches between sections were calculated for various discharges. Table A-4 lists cross section areas, surface widths, mean depth and travel times for selected discharges of 500, 1,000, 1,500, 2,000, 3,000 and 4,000 cfs in the Upper Nechako reach.

The Lower Nechako River between Nautley and Stuart was surveyed extensively by the International Pacific Salmon Fisheries Commission in 1950, 1951 and 1952. This earlier survey included stream cr~sssectioning at 48 stations spaced at about one-mile intervals and the water surface elevations for various discharges were referenced to the established discharge xeasurement station at VanderYLoof. The Vanderhoof station has been in operation since 1915. Comparing the stageldischarge relationship for Nechako River at Vanderhoof for 1950 with the 1974 data, it appears that the Lower Nechako River reach has changed l~ttle. The earlier physical survey data have therefore been used in the present calculations of predicted water temperatures. Table A-5 lists cross section areas, surface widths, mean depths and travel times for selected discharzes of 1,000, 2,000, 3,0Q0, 4,000 and 5,000 cfs in the Lower Nechako.

The data for all the cross sections are summarized in Table 22. The ttpper reach from Cheslatta to Nautley is narrower, shallower and faster than the reach from Nautiey to Stuart. TABLE 22. Summary of Physical Data for Nechako River at Selected Discharges

Cheslatta to Stuart Reach

Surface Mean

Tributary inflow to the Upper Nechakc reach an3 the Lower Nechako reach above Stuart during the period of sockeye migration is very small except for inflow from Kautley River. Measurement of tributary inflow in the Upper Nechako reach was made by the Fisheries and Marine Service during the summer of 1974. A total inflow of less than 10 cfs was measured for Twin Creek, Cutoff Creek, Copley Creek, Swanson Creek and Greer Creek during the period July to October, 1974. Observations by International Pacific Salmon Fisheries Commission crew during he summer of 1974 confirmed that only ino or flows from tributaries other than the Nautley entered the Nechako River above Stuart. Some water is removed from the Nechako River for domestic and irrigation purposes, but these quantities were not significant for the purpose of this study. Lt shouid be noted, however, that if future water with- drawals for these purposes are large, the amount of water released from the Nechako reservoir would have to be increased to compensate in order to maintain desirable water temperatures. No information is available with respect to the influence of groundwater flows on Nechako River temperatures. During the summer months, the groundwater flows are believed to be very small, with little effect on stream temperatures.

Method of Calculating Water Temperatures

The energy-budget method was used in this study to calculate river temperatures from known flows and known initial temperature sources. The method was similar to that used for the earlier Nechako River studies reported on in 1952, the Lake Hefner studies (Anderson, l952), and Columbia River studies (Raphael, 1961). The energy processes between a body of water and its environment are equated for a given set of conditions into a single expression of net heat exchange to or from the water.

The basic energy-budget equation as used for streams (Raphael, 1961) states that for a given intervai of time,

where (I = net change of energy in the body of water. Empirical formulae for the various components of the equation are as follows:

where 'SC = net incoming solar radiation incident to the surface (short wave radiation) corrected for reflection and cloud cover, in BTU/sq ftlhr. c = cloud cover index (0 - 10) Q~ = solar radiation, BTU/S~ft/hr. 'R = reflected solar radiation, BTUIsq ftlhr.

In this study, QS was measured with pyranographs at the river location. Calculations of heat gain were concerned only with clear days, thereby eliminating the cloud cover index, and a coefficient was determined to account for reflection and shade factor.

where Q = effective back radiation (long wave radiation) B in BTU/sq ftlhr.

Tw = water temperature in degrees Rankin. Ta = air temperature in degrees Rankin. d = Stefan-Boltzmann radiation constant = 0.1714 B = atmospheric radiation factor depending on cloud cover index and vapor pressure of air.

QE = 13.8192 W (ew - ea),

where Q E = energy change due to evaporation or conden- sation in BTU/S~ftlhr. W = wind speed in miles per hour. e = vapor pressure of saturated air at the W temperature of the water surface in inches of mercury. e = vapor pressure of the air in inches of mercury. a

QC = 0.004687 WP (tw - ta),

where Q = energy change due to the temperature differences C between the air and water interfaces (convection and conduction) in BTUIsq ft/hr. W = wind speed in miles per hour.

P = atmospheric pressure in inches of mercury. 0 tw = water temperature in F. t = air temperature in 0 F. a

QA = energy advected into or from the water by tributary streams, precipitation, etc., in BTU/sq ft/hr.

QB, QE, QC and Q can be either energy losses or gains A depending on meteorological conditions. Precipitation and tributary inflow from other than the Nautley River were neglected for this study.

The energy-budget equation requires that each stream travel time increment be analyzed separately, giving an estimated temperature change for the time interval. Manual analysis sometimes requires 2 or 3 trial-and-error calculations to balance the net heat exchange for the new temperature condition.

A computer program was developed (Saxvik, 1970) to solve temperature predictions in streams by the energy- budget method and at travel time increments of 1-hr. This program was used for all of the Nechako River temperature calculations. The 1-hr. travel increment required that all necessary meteorological data be tabulated for computer input on an hourly base. Likewise, the physical river data had to be tabulated on a 1-hr. travel time interval for each of the Nechako River reaches and for each of the discharges to be analyzed. To aid this tabulation, a separate computer program was developed in cooperation with the B. C. Hydro Computer Science Department. This program computes the travel distance and mean depth for a 1-hr. travel time for any given discharge and known cross sectional area and surface width. The results are listed in Tables A-6 and A-7.

To determine the stream exposure coefficients required for application of the energy-budget equation, test reaches were established in Nechako River during the 1974 field survey. Two test reaches were located in the Upper Nechako River. The first was between Irvines and Greer, a distance of 14.75 miles, and the second was between Greer and Larson, a distance of 7.62 miles. One test reach was located in the Lower Nechako River between Vanderhoof and Stuart, a distance of 26.49 miles. For test purposes, field measurements of water temperatures and weather were made on clear or near-clear days to observe maximum effects. Water temperatures were measured using hand thermometers at 15-min. intervals at upstream and downstream ends of the test reaches and also recorded continuously on recorders at some stations. Mobile weather station equipment was operated at either the upstream or downstream end of each reach during the tests. Tables A-8 and A-9 list the weather observations used in temperature test calculations.

Calculated water temperatures were then compared with 34 measurements of the actual water temperatures. Each calculation utilized the measured water temperature at the upstream end of the reach as the initial water temperature. Water travel distance and mean depth for each hour interval were calculated on the basis of actual discharges occurring during the tests. Computer test results for hourly periods with little - or no incoming radiation (evening, darkness and early morning hours) indicated that the calculated energy losses had to be increased by a factor of 1.4 to make the predicted water temperatures equal the actual measured values. To adjust the measured incoming solar radiation values for reflection and shade, each of the 34 tests was calculated using solar radiation coefficients varying from 1.0 to 0.5, in conjunction with the loss coefficient of 1.4. A summary of these calculations comparing the computed end temperatures nearest to the actual measured values for each of the tests is shown in Table 23. The mean difference between calculated and measured water temperatures was least with the coefficient of 0.7 (Table 24). A solar radiation coefficient of 0.7 and an energy loss coefficient of 1.4 were therefore used in the computer analysis for predicting water temperatures at reduced flows and with more extreme meteorological heating conditions.

The coefficients were substantiated by checks using data for 5 days in 1975. Hourly water temperatures from the thermograph record for the Nechako River above Stuart in 1975 were compared with hourly calculated temperatures for the same location. Temperature changes were computed for the Nechako River reach from Vanderhoof to the Stuart River confluence, a distance of 26.49 miles, using the thermograph records of hourly water temperatures at Vanderhoof as the initial conditions of the analysis. The analysis also utilized the weather conditions measured at Fort Fraser and the actual physical river conditions that occurred during the test period. A comparison of calculated and recorded hourly water temperatures for the Nechako River above Stuart for August 11 - 13 and September 13, 1975 (Figure 9), shows that the calculated temperatures were close to, but generally less than, the observed temperatures. TABLE 23. Comparison of Measured and Calculated Hourly Temperatures for Different Solar Radiation Coefficients

Test Reach and Date

August 29 - 30

Greer to Larson September 2

Greer to Larson September 3

Vanderhoof to Stuart August 30 to Sept. 1

Vanderhoof to Finmoore August 31 to Sept. 1

Vanderhoof to Stuart 2,120 40 0.8 65.22 66.50 September 1 - 3 0.8 65.23 66.00 0.8 65.79 60.00 0.7 65.71 65.80 0.6 65.42 65.00 0.5 65.24 04.80

TABLE 24. Mean Difference between Measured and Calculated Temperatures

Solar Number Mean Coefficient of Tests Difference 0 F

Examination was then made of water temperatures expected at other discharges and weather conditions. The temperatures that would have occurred at the lower end of the Cheslatta-to-Nautley and Nautley-to-Stuart reaches in 1974 were calculated for selected discharges for three periods: August 1 - 3, August 15 - 17, and September 1 - 3. These periods were selected because water arriving at the ends of these reaches on these dates had been exposed to greater heat input than on other days in the study period in 1974. However, considerably greater heating would have occurred under extreme weather conditions on these dates. For each of these periods, end temperatures were calculated for alternate hours for starting temperatures of 400 to 70'~in 5' increments in the Cheslatta-to-Nautley reach, and 40' to 75'~in 5' increments in the Nautley-to-Stuart reach. The travel times for each reach for selected discharges are summarized in Table 25. TABLE 25. Travel Time of Nechako River in Hours, Cheslatta- to-Nautley and Nautley-to-Stuart Reaches

Cheslatta to Nautley Nautley to Stuart Discharge cfs. 55.71 miles 60.32 miles

The calculated hourly end temperatures were then averaged to obtain mean daily temperatures and the highest daily mean for the 3-day period was graphed in relation to initial starting temperatures and discharges (Figures A-4 to A-9). In the Lower Nechako reach, the calculations showed that maximum mean daily temperatures occurred near Vanderhoof rather than at the Stuart confluence so the results were also plotted for this location (Figures A-10 to A-12). It should be noted that when using these graphs for predicting down river conditions for arbitrary starting temperatures and discharges the results give end temperatures based on the assumption that the same heat input occurs each day of water travel. From 4 to 7 days of water travel was required between Cheslatta and Stuart with starting flows of 500 to 4,000 cfs.

The graphs were then used to determine mean daily water temperatures for Nechako River above Stuart based on the starting water temperatures measured at Cheslatta in 1974. Starting with selected discharges and recorded temperatures at Cheslatta, the temperature above Nautley was determined. This flow and temperature were then combined with recorded Nautley River discharge and mean daily temperature to obtain a new discharge and a new mean daily temperature for the Lower Nechako River just below the Nautley confluence. Using these values, the temperatures near Vanderhoof and just above the Stuart confluence were determined.

Calculations for six assumed starting discharges at Cheslatta for each of the study periods, using the starting temperatures and Nautley River discharges and temperatures measured in 1974, showed that for these conditions mean daily temperatures in the Nechako, immediately above the Stuart would have exceeded 68'~for flows less than 4,000 cfs on all dates except September 1 (Table 26). Calculated temp- o eratures at the reduced discharges were from 1 to 12 F higher than the recorded temperatures at the actual discharges, since the calculated temperatures were based on clear, warm days, whereas actual weather conditions varied in the period. The climatic conditions during the study period in 1974 did not cause high river temperatures but comparison with conditions in 1951 and 1971 illustrates that much higher temperatures have occurred (Table 27). TABLE 26. Computed Temperatures of Nechako River above Stuart for 1974 Weather Conditions and Assumed River Flows at Cheslatta Compared to Recorded Temperatures for the Actual Discharge

Assumed Discharge, Actual Discharge, Calculated Mean Recorded Mean cfs. cfs. - Daily Temperature, Daily Temperature, Starting Date End Date at at Nechako Above at at Nechako Above 0 at Cheslatta at Stuart Cheslatta Stuart Stuart F -Cheslatta Stuart Stuart

Aug. 1, 1974 Aug. 7 500 2,100 69.8 6 1,000 2,600 69.9 5 1,500 3,140 69.7 5 2,000 3,640 69.4 5 3,000 4,640 68.7 5 4,000 5,640 67.8

Aug. 15, 1974 Aug. 21 500 1,690 21 1,000 2,190 19 1,500 2,700 19 2,000 3,200 19 3,000 4,200 19 4,000 5,200

Sept. 1, 1974 Sept. 8 500 1,400 7 1,000 1,900 6 1,500 2,410 5 2,000 2,910 5 3,000 3,910 5 4,000 4,910

* At Vanderhoof Calculated temperatures given above are the highest for the three days examined in each period. Starting temperatures at Cheslatta: August 1, 59.3O~,August 15, 61.0'~ and September 1, 59.5'~. TABLE 27. Temperatures and Discharges in Nechako River for the Days of Highest Mean Daily Water Temperatures in 1951, 1971, 1974 and 1975.

Nechako River Nechako River Vanderhoof above Stuart at Vanderhoof max. air temp 0 0 Date F cfs F

Aug. 31, 1951 July 31, 1971 Aug. 19, 1974 July 24, 1975

Furthermore, the highest temperatures were observed in both 1951 and 1971 at much higher discharges than in 1974 and 1975.

The previous studies, which utilized the climatic conditions occurring in 1951, showed there would be 15 days between July 16 and August 1 when mean temperatures of the Nechako above the Stuart would have exceeded the 68OF limit. On 10 of these days the temperature exceeded 70°F and on 4 days the temperature exceeded 71°~,with a maximum of 72.5'~. These temperatures are higher than calculated for the 1974 weather conditions, but still not as high as actually recorded in 1971.

Predicted Water Temperatures for Extreme Heating Conditions

Long-term air temperature records also indicate that the weather conditions occurring during the 1974 study period were less severe than could be expected in some years. The maximum air temperature at Fort St. James in July, 1974 was 83'~compared to the highest recorded maximum of 98'~ in 1941 (Table 7). The daily maximum at Vanderhoof in 1974 was 880 F compared to the highest recorded maximum of 104'~ in 1941 (Table 28). Air temperatures measured at Vanderhoof show that the maximum temperature in July, 1974 was equalled or exceeded in 41 out of 47 years of record and the maximum temperature in August, 1974 was equalled or exceeded in 12 out of 47 years of record (Table 28).

0 TABLE 28. Maximum Air Temperatures at Vanderhoof, in F To assess the effect of more extreme heating than observed in 1974, a series of weather conditions was simulated, using an average barometric pressure of 27.70 in., average wind velocity and humidity as measured in 1974 (Table A-3), maximum theoretical incoming radiation estimated from Kimball (1928) for Fort Fraser (Table A-lo), and mean hourly air temperatures from thermograph records at Finmoore on July 29 and August 10, 1960 (Table A-11). On clear days during the study period from August 2 to September 18, 1974, the radiation measured at Fort Fraser with the pyranograph used at the fixed weather station on Nechako River was 92 to 99% of the estimated maximum given by Kimball (1928). Kimball's estimates of maximum radiation received were therefore considered representative for the study area.

Daily maximum air temperature in 1960 reached 89'~ at Fort St. James and 92'~at Vanderhoof, and while these are considerably lower than observed in 1941, the 1960 records at Finmoore were the highest hourly data available. The air temperatures for July 29, 1960 were used for all days from July 24 to August 4, and the temperatures for August 10, 1960 were used for all days from August 5 to August 18. Using these data, the same procedure was followed as detailed for the 1974 data. The graphs showing calculated end temperatures for various discharges and starting temperatures are shown in Figures A-13 to A-1.8.

As a check on the accuracy of the procedure, the expected temperatures in the Nechako River above Stuart on the days of highest temperature at the end of July, 1971 were calculated and compared with the recorded temperatures, using actual discharges and starting from the recorded temperatures below the Nautley confluence. The results (Table 29) show that the calculated temperatures were lower than the recorded, indicating that even more extreme heating conditions should have been used. However, in view of the time required for preparation of records for a further computer run, the simulated weather conditions as described were used for approximating the expected mean daily water temperatures under extreme heating conditions. If the river flow had been less than in 1971, water temperatures would have been even higher. It is not possible to estimate the temperatures at reduced discharges in 1971 because temperatures were not measured at Cheslatta and because the estimated temperature below Nautley would exceed the upper limit of conditions studied.

TABLE 29. Comparison of Calculated and Measured Mean Daily Water Temperatures of Nechako River above Stuart River in 1971, using Simulated Extreme Weather Data

Calculated Measured Temperature Temperature 0 Date 0 F F

July 29 75.3 76.3 30 76.1 77.3 31 76.1 77.3 August 1 76.0 75.9 COOLING WATER DISCHARGE REQUIRED FOR TEMPERATURE CONTROL

Previous studies (Int. Pac. Salmon Fish. Comm., 1953) concluded that temperature in Nechako River could be controlled by release of cold water from Nechako reservoir. This is still the only means apparent to control temperature if flows in the Nechako are reduced for the Kemano I1 development.

The graphs constructed for the simulated extreme weather conditions were utilized to examine the temperatures that would result from releases of water from the Nechako reservoir. The extreme weather conditions were examined in conjunction with the Nautley River flow of 1,720 cfs and temperature of 68.0°F on July 28, 1960; 1,690 cfs at 69.8'~ on July 29, 1960; 2,750 cfs at 70.8OF on July 28, 1971 and 2,700 cfs at 70.5OF on July 29, 1971. The discharge and temperature combinations in 1960 produced the higher temperatures. The . end temperatures in the Nechako River above Stuart River for July 31, 1960 and July 31, 1971 are shown in Figures 10 and 11. As shown in Figure 10, about 3,950 cfs of 45'~cooling water would have been required for obtaining a mean temperature of 68'~in the Nechako River above Stuart River on July 31, 1960. For July 31, 1971 (Figure 11) the required 45'~ cooling water discharge was indicated by extrapolation to be about 4,400 cfs. On the basis of these data, it was assumed that a maximum cooling water discharge of 4,500 cfs would be required. Colder water could be obtained from the Nechako reservoir but temperatures lower than 45'~at this time of year could have a detrimental effect on the chinook salmon population (Environment Canada, 1977). Water with temperature of 50°F or higher would not provide the desired control of temperature within the range of cooling water discharges studied. 66 67 68 69 70 71 72 75 74 75 76 77 78

CALCULATED MEAN DAILY WATER TEMPERATURE (OF )

Figure 10. Effect of release of cooling water from Nechako reservoir on temperatures of the Nechako River above Stuart, July 31, 1960. 66 67 68 69 70 71 72 73 74 75 76 77 70 CALCULATED MEAN DAILY WATER TEMPERATURE (OF )

Figure 11. Effect of release of cooling water from Nechako reservoir on temperatures of the Nechako River above Stuart, July 31, 1971. Temperature records for Nechako River above Stuart in 1971 were used to estimate the volume of 45'~cooling water required. On the basis of the degree-days above 68 0 F, using 4,500 cfs for the maximum day, a volume of 107,000 acre- feet would be needed. Since the maximum flow required would take about 3 days to reach the Stuart confluence, it would be necessary to provide an additional 27,000 acre-feet of cooling water, for a total storage requirement of 134,000 acre- feet. In view of the long period of temperatures above 63'~ in 1971 compared to the other years of records, it is considered that this volume would be the approximate maximum of 45'~ cooling water required.

The duration of required cooling water releases was estimated on the basis of the sockeye migration period, weather conditions and the water travel time between the Upper Nechako and the Stuart confluence. The earliest date that temperature control would be required is July 20. However, it would be necessary to gradually increase the cooling water flow in the Upper Nechako to avoid scouring the river channel or adversely affecting resident fish. For conditions similar to those occurring in 1971 a cooling water flow of 1,500 cfs would be required at the Stuart confluence from July 20 to 24 and the flow would have to be increased to 4,500 cfs on July 30. This rate of increase, 3,000 cfs in 6 days, would be similar to the conditions observed in 1974, when the flow in the Upper Nechako increased from 1,200 cfs on July 12 to 4,600 cfs on July 18. This rate of increase did not appear to cause any adverse effect on native fish populations or on scouring the river bed.

Prior to the date when cooling water flows would be required, the flow in the Upper Nechako would be 1,200 cfs for protection of chinook salmon f_Environment Canada, 1977). This flow, which would presumably consist of surface flow from Cheslatta, would have to be replaced with 45'~cooling water when required. To provide 1,500 cfs of cooling water at the Stuart confluence on July 20, as would be eequired under conditions similar to those occurring in 1971, the 1,200 cfs of surface flow from Cheslatta Lake could be stored and the flow replaced with 1,200 cfs of 45'~water from the reservoir. For the 1971 conditions, this flow would have to be increased to 1,500 cfs and 4 days of travel time would be required between the Upper Nechako and the Stuart confluence. Under the 1971 conditions, therefore, the cooling water flow would have to begin about July 15.

Calculations were made to determine the required cooling water flows during the period August 25 to September 10 in order to estimate the latest date when temperature control would be required. For these calculations, the previously described 1974 weather conditions (Figures A-6 and A-9) were used. For each year from 1950 to 1975, the maximum daily cooling water requirement was calculated for the most adverse temperature and discharge condition for Nautley River in each year for the August 25 to September 10 period. The calculations showed that it would be necessary to provide temperature control for the Nechako River above the Stuart confluence as late as September 6. Prior to August 30, the required cooling water discharge would be greater than the minimum flow of 1,000 cfs required for protection of chinook salmon. From August 30 to September 6, the estimated maximum discharge of 45'~ cooling water would gradually reduce from 1,200 cfs to 200 cfs. with a concurrent increase in the Skins Lake releases to maintain a minimum river flow of 1000 cfs for ehinook spawning. Water temperatures were measured in Nechako reservoir on four days in 1974. All measurements were taken by bathythermograph in the vicinity of Kenney Dam. Table 30 lists the water temperatures at 10-ft. depth intervals on each of the test days. 0 Water at a temperature of 45 F for cooling purposes would generally be available at depths 75 to 95 ft.

It is possible that cooling water would be available from an alternate source, such as Cheslatta Lake. However, no location other than the Nechako reservoir was investigated in this study since no other logical source was apparent. The total quantity of cooling water available in the reservoir was not determined but the volume below 90 ft. depth in the reservoir between Kenney Dam and the sill (elev. 2644) at the outlet of the former Natalkuz Lake, approximately 20.4 miles from the dam, is estimated to be approximately 480,000 acre-ft., which is sub- stantially more than the estimated volume of cooling water required.

The rates and total amount of cooling water calculated here apply to the Nechako River above the Stuart confluence. Com- puter calculations indicate slightly higher water temperatures in the vicinity of Vanderhoof, which would require additional cooling water discharge. Records for 1974 also indicate possible further increase in temperature between Stuart confluence and Isle Pierre. Measurements show occasional temperature in- creases in the Stuart-to-Prince George reach and it is possible that additional cooling water would be needed for this section of the river in warm years. Data for 40 cross sections in the Stuart-to-Prince George reach were obtained by International Pacific Salmon Fisheries Commission in 1950 - 52. Further surveys would be required to determine stage/discharge relationships for these sections before calculations of temperatures at reduced flows could be made. TABLE 30. Bathythermograph Readings in Nechako Reservoir near Kenney Dam, in OF.

Depth July 13 July 27 Aug. 6 Aug. 22 Aug. 22 Sept. 9 Aug. 10 (ft) 1974 1974" 1974 1974 1974* 1974 1975*

0 55.5 60.8 63.0 59.6 10 55.3 60.8 62.1 59.6 20 55.3 60.7 61.9 59.3 30 55.3 60.6 61.9 59.3 40 55.3 60.1 61.8 59.4 50 55.2 57.2 58.4 58.4 61.4 59.5 59.4 60 54.5 55.5 61.0 52.5 7 0 54.1 53.7 59.0 47.0 8 0 52.0 47.5 53.5 44.3 90 47.7 44.3 45.0 43.2 10 0 44.0 46.0 42.7 42.7 43.5 42.5 45.0 110 41.4 41.5 41.7, 41.8 120 40.2 40.6 41.0 41.0 130 39.5 40.0 40.5 40.3 140 39.3 39.9 39.8 40.1 150 39.3 42.0 39 .8 39.6 41.2 39.8 42.1 160 39.3 39.8 39.5 39.7 17 0 39.7 39.4 39.7 180 39.6 39.3 39.7 19 0 39.5 39.3 39.7 200 41.9 39.5 39.2 41.9 39.7 41.9 210 39.4 39.2 39.7 220 39.4 39.2 39.7

* Measurements recorded by hand thermometer in water samples obtained for oxygen and nitrogen determination. PREDICTED EFFECT OF KEMANO I1 ON DISSOLVED GAS CONCENTRATION

The concentration of dissolved gases in Nechako reservoir water was investigated during the 1974 and 1975 field surveys. Dissolved oxygen and nitrogen concentrations and saturation levels were determined at various depths in the reservoir and in the Nechako, Nautley and Stuart Rivers.

Water samples were obtained from the Nechako reservoir just upstream from Kenney Dam. The samples were collected from various depths in a standard Van Dorn bottle, and were immediately transferred to standard 300 cc BOD bottles and cooled on ice to 32'~. Samples from the river downstream were taken directly in the BOD bottles. Field determinations of dissolved oxygen were done by the Winkler method, and dissolved nitrogen was measured by the microgasometric method (Scholander et al, 1955). Saturation solubilities were determined on the basis of concurrent barometric pressure at the water surface at the sampling location. Data are summarized in Tables 31, 32 and 33.

There was increasing supersaturation of dissolved nitrogen in the Nechako reservoir at depths below 50 ft. to as much as 112% at 200 ft. depth. Conversely, there was increasing deficit of dissolved oxygen below saturation at depths below 50 ft. to as low as 57% at 200 ft. depth. In the Nechako River below the Cheslatta confluence, there was 112% saturation of nitrogen, which is attributed to the plunge basin in the Cheslatta River below Cheslatta Falls. As the water flowed downstream to Fort Fraser, the concentration of nitrogen decreased by 0.84 mgll, indicating air equilibration at the air-water interfaces. There was a slight TABLE 31. Oxygen and Nitrogen Concentrations ip Nechako Reservoir near Kenney Dam

Oxygen Nitrogen Water x Satura- I Depth Tgmp mg/l tion mg/l % Saturation Date ft. F Rean Mean Mean Mean July 27, 1974 50 57.20 8.99 99.22 16.33 107.12 I

Aug. 22, 1974 50 60.98 7.65 88.95 15.83 108.44

Means are the average of three determinations, except those marked with an asterisk (*) which are the mean of two determinations. TABLE 32. Oxygen and Nitrogen Concentrations in the Upper Nechako River on August 22, 1974 Oxygen Nitrogen Water % Satura- Temp. mg/l tion o mg/l % Saturation Location F Mean Mean Plean Mean * - - I Below Cheslatta Falls 61.52 8.89 102.1 16.58 112.3 I At Greer Creek 60.80 8.55 96.8 16.08 107.7 I 1 *At Fort Fraser 58.10 8.56 91.7 15.74 99.9 I

Means are average of three determinations except those marked with an asterisk (*) which are the mean of two determinations.

TABLE 33. Oxygen and Nitrogen Concentrations in the Lower Nechako, Nautley and Stuart Rivers on August 12 - 14, 1975 Oxygen Nitrogen- Water % Satura- Temp. mg/l tion mg/l % Saturation Location 0 F Mean* Mean* Mean Mean

Nechako River at Fort 66.20 9.45 111.2 15.31 104.80 Fraser, August 13

Nechako River at 64.04 9.75 107.1 15.25* 98. OO* Vanderhoof, August 12

Nautley River, August 12

Stuart River near 66.24 9.25 103.4 16.46 108.07 mouth, August 14

Means are the average of three determinations except those marked with an asterisk (*) which are the mean of two determinations. supersaturation of oxygen below Cheslatta Falls, but the oxygen concentration stabilized downstream. The under- saturation values shown are the result of decreasing water temperatures at the time, and changes in barometric pressure. Measurements in 1975 on August 13 and 14, at a time when water temperatures were increasing, showed supersaturation in the Nechako River at Fort Fraser and in the Nautley and Stuart Rivers.

The data for the Upper Nechako River on August 22, 1974 were used to determine the reaeration coefficient K2 (Phelps, 1944) per hour of water travel for the 14-hr. reach from Cheslatta to Greer Creek, and the 23-hr. reach from Greer Creek to Fort Fraser (Table 34). The coefficient was determined on the basis of the excess dissolved nitrogen at constant temperature from Cheslatta to Fort Fraser. The available data are not sufficient to determine the reaeration coefficient for the reach from Nautley to Stuart but on the basis of lower velocity and turbulence in this reach, a coefficient of 0.004/hr. at 59.45'~ has been assumed for purposes of calculations.

If the Kemano I1 development was operated as proposed by the B. C. Energy Board, discharge in the Nechako River below Nautley would be almost the same as the discharge of the Nautley River, since there would be very little other inflow during critical summer periods. Calculations were made to assess the magnitude of changes in dissolved gases that might be expected under near extreme weather, using the Nautley River discharge and temperature on August 1, 1960 and 1971, and the dissolved gas concentration measured in the Nautley River on August 12, 1975. The calculations suggest that under these conditions the total gas concentration would be approximately 108% of saturation (Table 35). TABLE 34. Calculated Values of Reaeration Coefficient in the Upper Nechako River

0 Reach Temp. F K2(per hr.)

Cheslatta to Greer Creek 61.35 0.01

Greer Creek to Fort Fraser 59.45 0.0056

Average 60.4 0.007 2

TABLE 35. Calculated Concentration of Dissolved Oxygen and Nitrogen in Nechako River above Stuart with only Nautley River Inflow and Assumed near Extreme Weather and Initial Saturation Levels

Percent Saturation Nitrogen Oxygen Total

August 1, 1960 107.4

August 1, 1971 107.7

The average reaeration coefficient of 0.0072/hr. was used to calculate the changes in dissolved nitrogen and 0 oxygen in a flow of 4,500 cfs of 45 F water withdrawn from the Nechako reservoir. For the Cheslatta to Fort Fraser reach the calculations were performed in steps for 4-hr. intervals in the manner used by Dysart (1970) to approximate the integral for the conditions when temperature is,not constant (Keshavan -et -al, 1973). From Nautley to Stuart a reaeration coefficient of 0.004lhr. at 59.45'~ was again assumed. An estimate of the change in concentration of dissolved oxygen and nitrogen was made for this reach in a single step for the 1.75 days of travel time. The results (Table 36) show that in the Nechako River above the Stuart, the concentration of both oxygen and nitrogen would be approximately 115% of saturation. The total gas supersaturation in this case would also be 115%. This level of supersaturation of nitrogen or total gas, as previously described, would not be sufficient to produce rapid mortality, but would be sufficiently high to produce stress and/or impairment of some physiological processes which would increase susceptibility to disease.

If the cooling water was air-equilibrated at the point of release, the nitrogen supersaturation would be reduced only slightly above the Stuart, and oxygen supersaturation would be increased (Table 37). The net effect would be a reduction of total gas supersaturation from 114.8% to 113.7%.

TABLE 36. Calculated Nitrogen and Oxygen Concentration at Maximum Daily Water Temperature in A Cooling Water Flow of 4,500 cfs at 45'~from Nechako Reservoir under Near-Extreme Weather Conditions OXYGEN NITROGEN Percent Percent Satura- Satura- 0 Location Temp. F mg/l tion mg/l tion I Nechako Reservoir 45.00 9-49 87* 19.62 110* at Cheslatta 45.00 at Fort Fraser 61.34 9.64 107.6 18.21 119.8 Nautley River 73-04 10.09 128.2* 14.20 102.8* Nechako below Nautley 64.58 9.77 112.8 17.06 114.9 I Nechako above Stuart 70.34 9.40 115.2 16.32 114.9

* From records obtained in 1974 and 1975. TABLE 37. Calculated Nitrogen and Oxygen Concentration at Maximum Daily Water Temperature in A Cooling Water Flow of 4,500 cf s of 45'~ from Nechako Reservoir under near Extreme Weather Conditions with Aeration at Point of Release to Equilibrate with Air OXYGEN NITROGEN Percent Percent Satura- Satura- Location Temp. OF mg/l t ion mg/l tion

Nechako Reservoir 45.00 9.49 87°C 19.62 110" at Cheslatta 45.00 11.10 100 18.16 100 at Fort Fraser 61.34 10.53 117.5 17.35 114.0 above Stuart 70.34 9.82 120.3 15.93 112.2

* From records obtained in 1974 and 1975. VOLUME OF WATER REQUIRED FOR TRANSPORTATION FLOW

As described in an earlier section of this report, it was initially concluded that a flow of 1,200 to 1,500 cfs would be needed in the Nautley-to-Stuart reach to provide unimpeded upstream passage for sockeye. The river was examined in October, 1952, after closure of Kenney Dam, and some areas of extremely shallow water were observed at 600 to 800 cfs which could make fish migration difficult and cause delay. Further observations during salmon migration in August and September, 1953 indicated that adult sockeye migrated successfully at discharges as low as 1,100 cfs. On the basis of these observations, it was recommended that the flow should not be less than 1,000 cfs during the sockeye migration period (Int. Pac. Salmon Fish. Comm., 1953).

The Kemano I1 power development, as described in the B. C. Energy Board Report (1972), would result in almost complete impoundment of all Upper Nechako basin water for power usage. The report states that the mean monthly inflow to the Nechako reservoir from the Upper Nechako basin was 6,633 cfs based on 1928 - 1958 records. The average power flow to the existing Kemano plant is approximately 4,600 cfs, which leave 2,030 cfs as the average existing spill. The Energy Board Report indicates 1,870 cfs of this spill would be used for power, leaving a residual of 160 cfs. The Energy Board Report noted the possibility of obtaining supplemental flow from the Cheslatta system for fish protection as well as possible cold water flow releases from the Nechako reservoir but no criteria were suggested. Discharge records for Nautley River show that in 26 years of records there were 22 years when the discharge was less than 1,000 cfs in the sockeye migration period from July 20 to September 30 (Table 38). The lowest flow was 350 cfs, which occurred in September, 1951. As shown in Table 39, up to 50,178 acre-ft. would have been required for maintaining a flow of 1,000 cfs for the years of record, assuming no inflow from the Upper Nechako. Since part of the requirement for transportation water occurs later than the release required for temperature control, the estimated volume required for temperature control would not be sufficient for both temperature control and transportation water in some years. Since there is very little requirement for temperature control in September, the maximum volume of transportation water in addition to the volume required for temperature control would be the volume required in September, or approximately 30,000 acre-ft. TABLE 38. Minimum Daily Discharge of Nautley River from July 20 to September 30, for 1950 to 1975, in cfs.

Year July 20-31 August September

- 1950 - 7 7 4 488 1951 1230 67 5 350 1952 1490 712 492 19 5 3 2050 107 0 500 1954 2 29 0 2120 1690 1955 1320 1000 64 2 1956 848 585 419 1957 1360 1340 1110 1958 1380 846 7 18 1959 27 60 1580 1180 1960 1640 984 695 1961 1120 39 5 - 1962 2220 1220 761 1963 1510 920 588 19 64 2360 1660 1040 1965 1660 891 430 1966 1420 7 34 540 1967 1640 719 485 1968 1830 980 605 1969 1030 716 488 1970 1020 710 470 1971 2610 1450 878 1972 3320 1360 7 35 1973 1350 782 525 1974 1720 9 70 600 1975 950 680 520 b TABLE 39. Quantity of Water in Acre-Feet Required to Maintain 1,000 cfs in the Nechako River below Nautley in the Period July 20 to September 30, Assuming No Inflow from the Upper Nechako

July 20-31 August September Total Year Ac. Ft. Days Ac. Ft. Days Ac. Ft. Days Ac. Ft.

1950 4,946 22 22,744 30 27,690 1951 6,086 22 30,466 30 36,552 1952 5,236 15 26,690 30 31,926 1953 24,644 29 24,644 1954 1955 12,216 30 12,216 1956 1,980 11 17,960 31 30,238 30 50,178 19 57 1958 1,942 12 14,262 30 16,204 1959 1960 8 2 3 9,354 30 9,436 1961 15,136 25 15,136 1962 6,560 20 6,560 1963 61 0 5 15,812 30 16,422 1964 1965 66 0 5 22,740 30 23,400 1966 5,720 17 17,256 30 22,976 1967 1,476 4 23,136 30 24,612 1968 40 1 15,450 30 15,490 1969 10,508 30 26,420 30 36,928 1970 11,316 30 25,152 30 36,468 1971 854 7 854 1972 5,072 19 5,072 1973 4,664 18 22,808 30 27,472 1974 80 2 12,750 3 0 12,830 1975 300 5 12,634 31 24,620 30 37,554 POSSIBLE DOWNSTREAM EFFECTS OF FLOW DIVERSION

Thorough assessment of the effects on the salmon resources of environmental changes that could be caused by Ke- mano I1 requires evaluation of the combined effects of a number of possible consequences of flow diversion out of the Fraser system. These consequences must be considered for the Kemano I1 development in relation to the incremental effects of other hydroelectric and/or flood control diversions. Obvious effects of discharge, temperature and supersaturation changes in the Nechako system were examined in the present study but possible effects of environmental changes downstream in the Fraser River were not evaluated.

Available information indicates that the effects of the Kemano I1 diversion on Fraser River salmon would not be restricted to the Nechako River watershed. Since all or nearly all of the spring freshet discharge of the Upper Nechako system would be stored in the Nechako reservoir for power production at Kemano, the present spilling in the Nechako River would be further reduced by the amount of flow being discharged at the Skins Lake spillway under present conditions. From 1956 to 1973, spill discharges as high as 17,900 cfs have been recorded at Skins Lake compared to maximum daily flows as high as 38,100 cfs in Nechako River at the Fraser-Nechako junction.

A correlation has been observed between the discharge of the Fraser River at Hope during the period of Childo sockeye seaward migration and the survival of these fish during the period from their seaward migration until their return as adults (Dept, of Environment and Int. Pac. Salmon Fish. Comm., 1971). It is presumed from this correlation that reduced flow would reduce survival of all Fraser sockeye populations, including the Nechako River runs. Based on the average discharge measured at the Skins Lake spillway from 1957 to 1973, and allowing a minimum residual flow of 160 cfs as suggested by B. C. Energy Board (1972), the average flow reduction in May would be 6,578 cfs. ak.Hope. For sockeye smolts migrating during this period, the observed flow-survival relationship would indicate that this flow reduction would cause a reduction of 5.0% in the number of returning adult sockeye. Allowing an escapement of 20% of the total returning run, the catch would have to be reduced by 6% to adjust for the reduced smolt-to-adult survival rate.

The estimated reduction of 5.0% in sockeye survival would be additional to the reduction already occurring as a result of the flow reduction caused by Kemano I. The combined effect of Kemano I and I1 can be estimated on the basis of the natural discharge at the present site of Kenney Dam. Flows were estimated for this location for a 23-year period (1930 to 1952) prior to filling of the Nechako reservoir. The average May discharge was about 10,281 cfs. If this flow was reduced to only 160 cfs, the observed flow-survival relationship would indicate a reduction of 7.7% in sockeye survival. The total sockeye catch in the commercial and Indian fisheries would have to be reduced by 9.6% to allow adequate escapement to adjust for this reduced survival.

Another consequence of diverting flow out of the headwaters of the Fraser system is that the summer water temperatures in the Fraser River would be higher because of the reduced volume of water and the longer travel time. Data for Horsefly River sockeye indicates increasing prespawning mortality as the average daily maximum water temperature at Hell's Gate rises above 60'~during migration of the run Cine. Pac. Salmon Fish. Corn., 1974). The increased heating also might adversely affect the fish due to gas supersaturation as well as exposure to higher water temperatures. The average discharge at the Skins Lake spillway during July and August under present conditions is approximately 7,056 cfs. if only 160 cfs residual flow was provided, the summer flow at Hell's Gate would be reduced by an average of 6,896 cfs. Studies made in connection with flood control for the Fraser River system (Fraser River Board, 1963), indicated that this flow reduction would result in an increase of O.~~Fin the maximum mean daily river temperature at ell's Gate. The combined effect of Kemano I and I1 would reduce the discharge from the estimated July - August average of 10,338 cfs to only 160 cfs, with the result that the mean daily water temperature at Hell's Gate would increase approximately 0 0.9 F under maximum heating conditions.

An inverse relationship has also been shown between the total volume of Fraser River discharge at Hope from June 1 to September 15 and the duration of upstream migration of Adams River sockeye (Gilhousen, 1960). Elimina- tion of the present average spill of 6,000 cfs at Skins Lake during this period would extend the period of entry into the Fraser by 1 or 2 days. This delay could reduce productivity of the run as a result of less favourable environmental conditions or later-than-normal spawning and incubat ion.

It is also possible that the reduced flow and altered environmental conditions in the estuary, as well as in the lower Fraser, would favor squawfish and other predators and this change could significantly reduce salmon production because of additional predation and increased disease trans- mission. If other flow diversions from the Fraser River are also undertaken, such as the McGregor River diversion, the foregoing downstream effects would be cumulative, with a total impact greater than that attributed to the Nechako diversion alone. CONCLUSIONS

1. For protection of adult sockeye salmon, which migrate through Nechako River in the period July 20 to October 5, the following conditions should be obtained:

0 a > Mean daily water temperature should not exceed 68 F. b ) River discharge should not be less than 1,000 cfs. c > Total dissolved gasses should not exceed 110% of saturation.

2. Inthe years since 1952, when all or part of the Nechako River was diverted for the Alcan development, high water temperatures have occurred in some years but because of fortuitous --- timing of the sockeye runs, the small numbers of fish present during periods of high temperature and infrequent observations - .- of the river during these periods, no mortalities of sockeye attributable to high temperature have been reported in Nechako River.

3. The Kemano I1 development as visualized by the B.C. Energy Board (160 cfs minimum flow, with no cooling water) would reduce flow in the Nechako River to such an extent that the foregoing requirements could not be fulfilled:

a) Water temperature would exceed the lethal limit for 0 sockeye. Mean daily temperatures as high as 77.3 F were recorded in the Nechako River above the Stuart confluence in 1971 and even higher temperatures would have occurred if the flow had been reduced as proposed for the Kemano I1 development.

b) The residual flow would not provide adequate river widths and depths for safe migration of sockeye. Discharges lower than 1,000 cfs in the Nechako River below the Nautley confluence would occur in 21 out of 26 years during the period July 20 to September 30.

c) The concentration of dissolved gases might exceed 110% of saturation but calculations based on assumed rates of reaeration suggest that the allowable limit would not be exceeded.

4. Mean daily water temperature in the Nechako River above Stuart confluence could be controlled to 68'~under near- extreme climatic conditions by release of up to 4,500 cfs of 45'~water from the Nechako reservoir into the Nechako River near Cheslatta. A total volume of approximately 134,000 acre- feet would be required for a year such as 1971, and is considered to be near the maximum requirement. It is estimated that approximately 480,000 acre-feet at a temperature of 45'~ or less could be obtained from the Nechako reservoir in the 20.4 - mile reach above Kenney Dam.

5. This discharge of cooling water would result in a total dissolved gas concentration of approximately 115% of saturation when the water reached the confluence with the Stuart River. This amount of supersaturation would not result in rapid mortality, but would stress the sockeye and/or impair some physiological processes, which could increase susceptibility to disease. Air equilibration of the cooling water at point of release would reduce the supersaturation by about 1%. Consequently, the criterion that total dissolved gas concentration should not exceed 110% of saturation could not be fulfilled. Methods of reducing these supersaturation levels would therefore have to be developed. 6. The required minimum flow of 1,000 cfs in the Nechako River below the Nautley confluence could be provided by release of water from the Nechako reservoir. The maximum quantity required would be approximately 30,000 acre-feet in addition to requirements for temperature control.

7. Without provision for temperature control, the reduct ion in flow in the Nechako River that would occur with the Kemano I1 development would result in higher water temperatures in the Nechako River which at times would be high enough to be lethal to adult sockeye during their migration, and at other times would impohe an additional stress on the soclieye which could result in death on their spawning ground prior to spawning.

With provision of temperature control, the problems associated with temperatures would be alleviated, but the supersaturation of dissolved gases would reach levels that would impose a stress on the sockeye which also could result in death.

Thus the proposed Kemano I1 development would have unavoidable adverse effects on the environment within the Nechako River which would result in increased probability of losses of sockeye salmon enroute to their spawning grounds in the Nechako River system. Such losses would reduce the production of sockeye from the current runs to the system and the large production potential known to be available in the rearing areas in the Nautley and Stuart tributary systems would also be reduced.

8. The effects of the Kemano I1 project on flows, water temperatures and dissolved gas levels in Nechako River above the Stuart confluence were studied in the present investigation since this portion of the river was considered to be the most critical but these studies indicate that possible changes in Nechako River below the Stuart and in the Fraser River downstream from the Nechako should also be studied. The indicated cooling water discharges would limit the mean daily temperature to a maximum of 68 0 F above the Stuart confluence but higher discharges might be necessary for controlling temperatures below Stuart River. Further observations should also be made to determine re-aeration factors in Nechako River downstream from the Nautley.

9. Consideration must also be given to possible adverse downstream effects of flow reduction due to Kemano I1 in combination with other Fraser River diversion projects on the survival of all Fraser River salmon populations. LITERATURE CITED

Allen, R.L. and A.C. Moser. 1967. Rockey Reach fall chinook salmon spawning channel. State of Wash. Dept. of Fish. Ann. Rept. 1965 - 1966. 40 p.

Aluminum Company of Canada. 1952 - 1974. A study of salmon migration and spawning in the Nechako River System. Ann. Repts.

Anderson, E.R. 1952. Energy budget studies. Water Loss Investigations, Lake Hefner Studies. Tech. Rept. U.S. Geol. Survey Vol. 1:71-119.

Brett, J.R. 1965. The swimming energetics of salmon. Scien. Amer. Vol. 213, 2:80-85. - . Brett, J.R, and N.R. Glass. 1973. Metabolic rates and critical swimming speeds of sockeye salmon (Oncorhynchus nerka) in relation to size and temperature. Jour. Fish. Res. Board Can. 30:379-387. ~--

British Columbia Energy Board. 1972. Provincial power study Val. 1-10, ui th App.

Canada Department of Environment and International Paci,fic Salmon Fisheries Commission. 1971. Fisheries problems related to Moran Dam on the Fraser River. 206 p.

Chambers, J.S. 1963. Propagation of fall chinook salmon in McNary Dam experimental spawning channel. State of Wash. Dept. of Fish. Summary Rept. 1957 - 1963. 48 p.

Coutant, C.C. 1969. Responses of salmonid fishes to acute shock. -In D.W. Pearce (ed.), Pac. Northwest Lab. Ann. Rept. for 1968 for the USAEC Div. of Biol. and Med., 2:2.19-2.26.

Department of Fisheries of Canada, International Pacific Salmon Fisheries Commission and Fisheries Research Board of Canada. 1951. Report on the fisheries problems created by the development of power in the Nechako-Keniano-Nanika River sys tems, 55p. Department of Fisheries of Canada and International Pacific Salmon Fisheries Commission. 1952. Report on the fisheries problems created by the development of power in the Nechako-Kemano-Nanika River systems, Supplement 1. 42 p.

Dysart, B.C., 111. 1970. Water quality planning in the presence of interacting pollutants. Jour. Water Poll. Control Fed., 42:1515-1529.

Ebel, W.J. 1970. Dissolved nitrogen surveys of the Columbia and Snake Rivers. U.S. Bureau of Commercial Fisheries, Seattle, Wash. Rept. 17 p.

Environment Canada. 1977. Chinook Salmon Studies on the lJechako River. Relative to the Potential Kemano I1 Development, (Vol. 3).

Environment Canada. Meteorological observations in Canada, Atmospheric Environment Service, monthly publications.

Environment Canada. Surface water data, British Columbia. Inland Waters Branch, Ann. publs.

Federal Water Pollution Control Administration. 1968. Industrial waste guide on thermal pollution. U.S. Dept. of Interior, Corvallis, Oregon, Rept. 112 p.

Fraser River Board. 1963. Flood control and hydroelectric power in the Fraser River basin. Final Report. 106 p. + App.

Gilhousen, P. 1960. Migratory behavior of Fraser River sockeye. Int. Pac. Salmon Fish. Comm., Prog. Rep. 7. 78 p.

Harvey, H.H. 1975. Gas diseases in fishes - a review. -In W.A. Adams (ed.), Chem. and Phys. of Aqueous Gas Solutions: 450-485.

International Pacific Salmon Fisheries Commission. 1942. Mortality of fish, Quesnel area. R.W. Simmons (ed.), unpublished.

International Pacific Salmon Fisheries Commission. 1953. A review of the sockeye salmon problems created by the Alcan project in the Nechako River watershed, 28 p. International Pacific Salmon Fisheries Commission. 1962. Ann. Rept. for 1961. 44 p.

International Pacific Salmon Fisheries Commission. 1972. Proposed program for restoration and extension of the sockeye and pink salmon stocks of the Fraser River. 91 p.

International Pacific Salmon Fisheries Commission. 1973. Temperature tolerance of adult sockeye. J.A. Servizi (ed.), unpublished.

International Pacific Salmon Fisheries Commission. 1974. Ann. Rept. for 1973. 54 p.

Keshavan, K. G.S. Sornberger and C.I. Hirshberg. 1973. Oxygen sag curve with thermal overload. Jour. of the Environmental Eng. Div., A.S.C.E. V. 99, EE5: 569-575.

Kimball, H.H. 1928. Monthly Weather Review, 56: 393-398.

Meekin, T.K. and A.C. Moser. 1966. Rocky Reach fall chinook salmon spawning channel 1964 brood. State of Wash. Dept. of Fish. Ann. Rept. July 1, 1964 - June 30, 1965. 27 p.

Nebeker, A.V. and J.R. Brett. 1974. Effects of gas-supersaturated water on survival of Pacific salmon and steelhead smolts. Research summary, Western Fish Toxicology Station, Corvallis, Oregon, U.S.A. Abstract.

Nebeker, A.V., D.G. Stevens and R.K. Stroud. 1976. Effects of air-supersaturated water on adult sockeye salmon - Jour. Fish. Res. Board Can. 33: 2629-2633.

Phelps, E.B. 1944. Stream sanitation. Publ., John Wiley and Sons, Inc. New York. 276 p.

Raphael, J. M. 1961. The effect of Wanapum and Priest Rapids dams on the temperature of the Columbia River. Rept. P.U.D. 2, Grant County, Wash. 44 p.

Saxvik, P.B. 1970. Computer program for estimating temperature changes in streams. Int. Pac. Salmon Fish. Comm., unpublished. Scholander, P.E., L. Van Dam, C. Lloyd Claff and J. W. Kanwisher. 1955. Microgasometric determination of dissolved oxygen and nitrogen. The Biol. Bul. 109(3): 328-334.

Snyder, G.R. and T. H. Blahm. 1971. Effects of increased temperature on cold-water organisms. Journ. Water Poll. Control Fed., 43: 890-899.

Stroud, R.K., G.R. Bruck and A.V. Nebecker. 1975. Pathology of acute and chronic exposure of salmonid fishes to supersaturated water. --In W.A. Adams (ed.), Chem. and Phys. of Aqueous Gas Solutions: 435-449.

Stroud, R.K. and A.V. Nebeker. 1975. A study of the pathogenesis of gas bubble disease in steelhead trout. Proc. Gas- Bubble Disease Workshop, Battelle Northwest, Richland, WA.

Tuyttens, J.P. 1974. Nechako River warm water 1971. Int. Pac. Salmon Fish. Comm., personal communications.

Water Quality Criteria. 1972. Dissolved Gases. Report of the committee of Water Quality Criteria. Nat. Acad. of Scien. and Nat. Acad. of Eng. Wash. D.C.: 131-139.

Wedemeyer, B. 1970. The role of stress in the disease re- sistance of fishes. In S.F. Sniezko (ed.), A symposium of diseases in fish and shellfishes, Amer. Fish. Soc., Wash, D.C. Special Publ. 5. 526 p.

SOCKEYE SALMON STUDIES ON THE NECHAKO

RIVER RELATIVE TO THE POTENTIAL

KEMANO I1 POWER DEVELOPMENT.

APPENDIX APPrnIX LIST OF TABLES

Page

0 A-1 Mean daily water temperatures, F. Nechako River below Cheslatta, 1974. Nechako River below Greer Creek, 1974 Nechako River at Fort Fraser, 1974-75. Nechako River at Vanderhoof, 1974-75. Nechako River above Stuart River, 1974-75. Nechako River at Isle Pierre, 1974. Nechako River at Prince George, 1974. Nautley River, 1974-75. Stuart River above Nechako River, 1974-75.

A-2 Water temperaturgs of Nechako River at mobile weather stations, 1974, F. A-3 Weather data. Incoming solar radiation at Fort Fraser weather station 1974, BtU/sq ft/hr.

Air temperature at Fort Fraser weather station 0 1974, F. Humidity at Fort Fraser weather station 1974, %.

Barometric pressure and wind speed at Fort Fraser weather station, 1974. 0 Air temperatures at mobile weather stations 1974, F.

Wind speed at mobile weather stations 1974, m~h.

Humidity at mobile weather stations 1974, %.

Barometric pressure at mobile weather stations 1974, " Hg. solar radiation at mobile weather stations 1974,Incornin& B u/sq ft/hr.

Incoming solar radiation at Fort Fraser weather station 1975, Btu/sq ft/hr.

Air temperatures at Fort Fraser weather station 0 1975, F. Page Humidity at Fort Fraser weather station 1975, %. 37

Barometric pressure and wind speed at Fort Fraser weather station, 1975.

Physical characteristics of Nechako River, Cheslatta to Nautley reach, from 1974 survey.

At Discharge = 500 cfs At Discharge = 1000 cfs kt Discharge = 1500 cfs At Discharge = 2000 cfs kt Discharge = 3000 cfs xt Uischarge = 4000 cfs

Physical characteristics of Nechako River, Nautley to Stuart reach, from 1950-52 survey.

At Discharge = 1000 cfs At Discharge = 2000 cfs At Discharge = 3000 cfs At Discharge = 4000 cfs At Discharge = 5000 cfs

Calculated water travel distance and mean depth for hourly time intervals, Nechako River, Cheslatta to Nautley reach.

iit Discharge = 500 cfs xt Discharge = 1000 cfs kt Discharge = 1500 cfs at Discharge = 2000 cfs xt Discharge = 3000 cfs kt Discharge = 4000 cfs

Calculated water travel distance and mean depth for hourly time intervals, Nechako River, Nautley to Stuart reach.

kt Discharge = 1000 cfs At Discharge = 2000 cfs xt Discharge = 3000 cfs At Discharge = 4000 cfs kt Discharge = 5000 cfs

Hourly weather summary for Nechako Hiver near Greer Creek ~ugust29 -Sept ember 3, 1974. 7L

Hourly weather summary for Nechako River near Vanderhoof August 29-September 3, 1974. 77

Theoretical maximum incoming solar radiation at Fort Fraser latitude, July 24-August 18.

Hourly air temperature at Finmoore, July 29 and August 10, 1960, 0 F. 81 APPENDIX

LIST OF FIGURES

Figure Page

A-1 Discharge rating curve for Nechako River at Irvines above Twin Creek, 1974 data. 82

Discharge rating curve for Nechako River below Greer Creek, 1974 data. 83

Discharge rating curve for Nechako River at Fort Fraser, 1974 data.

Calculated mean daily water temperatures for Nechako River above Nautley on August 3 with 1974 weather conditions. 8 5

Calculated mean daily water temperatures for Nechako River above Nautley on August 17 with 1974 weather conditions. 86

Calculated mean daily water temperatures for Nechako River above Nautley on September 1 with 1974 weather conditions. 87

Calculated mean daily water temperatures for Nechako River above Stuart on August 3 with 197.4 weather conditions.

Calculated mean daily water temperatures for Nechako River above Stuart on August 17 with 197.4 weather conditions.

Calculated mean daily water temperatures for Nechako River above Stuart on September 2 with 1974 weather conditions.

Calculated mean daily water temperatures for Nechako River near Vanderhoof on August 3 with 1974 weather conditions.

Calculated mean daily water temperatures for Nechako River near Vanderhoof on August 17 with 1971, weather conditions.

Calculated mean daily water temperatures for Nechako River near Vanderhoof on September 2 with 1974 weather conditions.

Calculated mean daily water temperatures for Nechako River above Nautley on August 1 with near maximum weather conditions.

Calculated mean daily water temperatures for Nechako River above Nautley on August 15 with near maximum weather conditions.

Calculated mean daily water temperatures for Nechako Hiver above Stuart on August 1 with near maximum weather conditions. 96

Calculated mean daily water temperatures for Nechako River above Stuart on August 15 with near maximum weather conditions. 97

Calculated mean daily water temperatures for Nechako River near Vanderhoof on xugust 1 with near maximum weather conditions. 98

Calculated mean daily water temperatures for Nechako Hiver near Vanderhoof on August 15 with near maximum weather conditions. 99 0 Table A-1. Mean daily water temperatures, F. Nechako River below Cheslatta, 1974.

Date July Augus t September 0 Table A-1. Mean daily water temperatures, F. Nechako River below Greer Creek, 1974.

1974 Date J~Y August September 0 3 Table A-1. Mean daily water temperatures, F. Nechako River at Fort Fraser,

1974 1975 Uate July August September July August September 0 Table A-1. Mean daily water temperatures, F. Nechako River at Vanderhoof, 4 1974-75.

1974 1975 Date J~Y August September July August September 0 5 Table A-1. Mean daily water temperatures, F. Nechako River above Stuart River, 1974-75

1974 1975 Date J~Y August September July August September Table A-1. Mean daily water temperatures, OF. Nechako River at Isle Pierre, 1974

------1974 Date J~Y AuWt September 0 Table A-1. Mean daily water temperatures, F. Nechako River at Prince George, 1974

1974 Date July August September 8 Table A-1. Mean daily water temperaturar, 0 F. Nautlsy River, 1974-75.

Date J~Y August September July August September Table A-1. Mean daily water temperatures, 0F. Stuart River above Nechako 9 River, 1974-75.

1974 1975 Date J~Y August September J~Y August September 10 Table A-2. Water temperatures of Nechako River at mobile weaQher stations, 1974, in OF.

Hour Interval Date and Location 8-9 9-10 10-11 11-12 12-13 13-l.4 l.4-15 15-16 16-17 17-18 18-19

Finmoore July 29 63.6 64.3 64.7 65.5 65.2 65.2 65.4 Aug. 30 64.6 65.2 65.9 66.5 67.2 67.8 68.0 Sept. 1 65.0 65.6 66.2 66.8 67.3 67.7 Vanderhoof July 29 61.2 62.7 63.4 64.0 64.5 64.9 65.2 Aug. 30 63.964.5 65.4 66.4 67.6 68.7 69.5 Sept. 1 62.8 63.4 64.5 65.7 66.5 67.4 67.8

Fort Fraser July 30 61.3 61.6 62.1 62.4 62.7 62.9 63.0 63.0 ~ug. 26 59.2 59.8 60.7 61.5 61.9 62.4 62.7 Aug. 28 61.8 62.3 62.7 63.3 63.9 64.6 66.2 65.6 Sept. 2 60.9 6 62.0 62.7 63.4 64.0

Larsonl s July 30 Aug. 26 Aug. 28 Sept. 2 Sept. 3 Greer Creek Aug. . 29 61.7 62.1 62.8 63.6 64.5 65.3 65.8 Sept. 3 61.3 61.9 62.7 63.4 63.8 64.5 64.8 Irvine s Aug. 29

Note: Water temperatures are mean of four observations at 15-minute intervals within each hour. 11 Table A-3. Weather data. Incoming solar radiation at Fort F'raser weather station 1974, ~tu/s~it/hr.

Hour Aug. 1 Aug. 2 Aug. 3 Aug. 4 Aug. 5 Aug. 6 Aug. 7 Aug. 8

Hour Aug. ? Aug.10 Aug.11 Aug.12 Aug.13 Aug.I.4 Aug.15 Aug.16 Table A-3. Continued. Weather data. Incoming solar radiation at Fort Fraser weather station 1974, ~tu/safth. 12 Hour Aug.17 Aug.18 Aug.19 Aug.20 Aug.21 Aug.22 Aug.23 Aug.21,

Hour Aug.25 Aug.26 Aug.27 Aug.28 Aug.29 Aug.30 Aug.31 Sept.1

Hour ~ept.2 ~ept.3 ~ept.4 Sept .5 Sept .6 Sept -7 Sept. 8 Sept 9 Table A-3. Continued. Weather data. ,Incoming solar radiation at Fort Fraser weather station 1974, Btu/sa ft/hr. 13 Hour ~ept.lo ~ept.ll ~ept.l2 ~ept.l3 Sept .l4 Sept .l5 ~ept Sept 17

Hour Sept .l8 0 14 Table A-3. Weather data. Air temperature at Fort Fraser weather station, 1974, F.

Hour Aug.1 Aug.2 ~ug.3 Aug.4 Aug.5 Aug.6 Aug.7 Aug.8

Hour Aug.9 Aug.10 Aug.11 Aug.12 Aug.13 Aug.U Aug.15 Aug.16 Table A-3. Continyjed. Weather data. Air temperature at Fort Fraser weather station, l97L. F* 15 Hours Aug.17 Aug.18 Aug.19 Aug.20 Aug.21 Aug.22 Aug.23 Aug.24 Table A-3. Contin~ed. Weather data. Air temperature at Fort Fraaer weather station, 197L. F. 1 L Hour ~ept.2 Sept .3 Sept .4 Sept .5 ~ept.6 Sept .7 Sept. 8 Se?t 9

Hour Sept.10 Sept.11 Sept.12 Sept.13 Sept.U. Sept.15 Sept.16 Sept.17 Table A-3. Continy,ed. Weather data. Air temperature at Fort Fraser weather station, 1974, F. I' Hour Sept .l8 Table A-3. Weather data. Humidity at Fort Fraser weather station, 1974, dP. 18

Hour Aug.1 Aug.2 Aug.3 Aug.4 Aug.5 Aug.6 Aug.7 Aug.8 A.ug.9 Aug.10 Aug.11. Aug-12

Hour Aug.13 Aug.14 Aug.15 Aug.16 Aug.17 Aug.18 Aug.19 Aug.20 Aug.21 Aug.22 Aug.23 Aug.24

97 ?6 83 90 85 74. 92 99 88 100 100 98 98 80 3L 8 5 79 95 35 59 103 192 98 100 82 93 84 82 96 9.4 87 100 100 100 100 84 99 o^L 86 93 93 37 193 100 100 97 84 10G 36 87 86 95 90 100 100 96 92 80 95 8i, S3 81, 91. 9& 100 100 lo0 88 76 84 79 78 85 82 C32 100 100 83 32 72 75 7 5 72 78 77 85 96 100 7: 71 66 67 70 5 5 '70 76 ?5 83 78 6 1 63 61 61 47 6 1 66 74 72 71 5 3 5 7 5 5 56 64 59 61 71 6874 67 60 52 5 5 51 52 61 5 8 62 63 67 68 54 '; 3 / r 5 1 , * 5 i 5 1 51 57 64 oi. 6 7 68 5 1 5 0 50 52 53 57 56 6 j 5 9 67 68 4? L8 I+ 8 51 55 5 5 54 6 1 57 64 7: 51 $8 L7 52 66 5 )+ 53 71 57 64 87 5 1 c r 49 5 1 57 66 53 J; 77 53 63 8 8 50

50 66 6 5 59 L: 5 59 83 51 81, 76 51 5L 80 75 63 i; l. 67 89 6 2 93 73 56

79 GI. 81 69 67 724 ! 94 6 5 98 3 3 62 84 82 82 79 72 79 96 6 c, 38 90 65 88 86 81 S:l 71 86 37 P!3 7 0 ? 36 69 90 8 9 83 78 6 9 90 100 81 99 98 73 93 89 "3 81 70 OD 100 83 100 99 76 Table A-3. Continued. Weather data. Humidity at Fort Fraser weather station, 1974, %.19

Hour Sept.5 Scpt.6 Sept.7 Sept.8 Sept.9 Sept.10 Sept.11 Sept.12 Sept.13 Sept.14

90 100 99 96 99 76 98 o 1 100 99 96 99 96 98 ?2 100 99 96 100 9 5 9 7 ?j loo 99 96 loo 96 97 94 100 99 96 100 98 97 9:+ 100 100 96 100 99 98 93 loo loo 96 loo 94 95 92 100 93 96 100 86 89 93 100 96 96 97 81 82 96 100 96 96 88 79 77 92 9 5 9 5 9 5 34 7 5 71 99 90 9 5 95 8 5 71 69 100 86 74 95 85 67 6 5 100 80 93 9 5 89 66 6 1 100 82 93 95 9 3 67 59 100 91 9"k 9 5 96 71 60 100 9 3 95 96 98 77 64 100 9 5 96 96 99 83 74 loo 97 96 96 loo 90 9 2 loo 9 8 96 96 loo 9 5 9L 190 98 96 96 100 96 9 5 100 9i: 96 96 5") 96 96 100 92 97 97 97 97 9 7 100 99 97 98 9 6 98 99 Table A-3. Continued. Weather data. Wdity at Fort F'raser weather station, 1974, %.20

Hour Sept .l5 Sept .l6 Sept .l7 Sept .l8

98 loo loo 100 100 100 100 ?6 83 72 60 62 57 5 5 5 5 58 6 2 68 79 88 90 92 93 93

Table A-3. Continued. Weather data. Barometric pressaae and wind speed at Fort Fraser weather station, 1974. 22

Barometric Wind Barometric Wind Time Pressure Speed Wind Time Pressure Speed Wind Date PST "Hg. mph Direction Date PST Qg , mph Direction

Aug. 16 0700 0900 1100 1300 1500 1700 Aug. 25 0700 Aug. 17 0700 0900 1100 1200 1300 1500 1500 1700 1700 1903 1900 Aug. 26 0700 Aug. 18 0730 0900 293" 1100 1130 1600 1330 1530 1900 2100

Aug. 19 0800 iiO0 1300 1500 Aug. 28 0700 1700 0900 1930 1100 1502 Aug. 20 0700 1730 090C 1300 1530 1800

E Aug. 30 0530 27.70 0 0900 27.70 3 Aug. 22 0700 E 1100 27.69 0 1300 27.66 3 1500 27.61 4-19 iJ 1700 2'7.5'7 0 W v ~ug.31 0730 2-7-67 0 id 1030 27.69 3.25 E Yd 1230 27.69 2.61 E 1600 27.67 6.77 NE goo 2'7.69 2.42 SE Table A-3. Continued. Weather data. Barometric pressure and wind speed at Fort fiaser weather station, 1974. 2 3

Barometric Wind Barometric Wind Time Pressure Speed Wind Time Pressure Speed Wind Date PST "Hg. mph Direction Date PST "Hg. rnph Direction

Sept. 1 Sept. 9

Sept. 2 0730 0930 1230 2003

Sept. 3 0530 0730 1100 1300 1500 1730 1930 Sept. 4 0530 0730 1000 1200 1500 1700 Sept. 5 0530 0930 1130 1500 Sept. 6 0530 1100 1500 1700

Sept. 7 0630 0830 1030 1530 1730 Sept. 3 0700 1100 11+30 1600 Table A-3. Continued. Weather data. Barometric pressure and wind speed at Fort baser wbather station, 1974. 2 4 Barometric wind Time Pressure Speed Wind Date PST "Hg. mph Direction 0 Table A-3. Weather data. Air temperatures at mobile weather stations, 1974, F. 2 5

- ~ ~p ~ - -- - ~ - - Hour Interval Location Date 9-10 10-11 11-12 12-13 13-14 -115 -16 16-17 17-18 18-19

Finmoore July29 72.8 74.9 Aug. 30 65.2 68.5 80.9 Sept. 1 63.8 70.6

Vanderl~oof July 29 63.2 63.9 70.7 Aug. 30 58.4 63.6 Sept. 1 63.0 66.1 70.2 Fort Fraser July 30 77.0 Aug. 26 67.8 ~ug.25 64.2 76.0 Sept. 2 67.5 77.1

Larsonl s July 30 71.9 AU~.26 69.5 AU~.28 64.2 76.0 Sept. 2 SO. 4 Sept. 3 75 .O 77.0

Greer Creek Aug. 29 73.6 23.4. Sept. 3 68.1 73.9 83.1

Note: Air temperatures are mean of four observatiolls at 15-minute intervals within each horn. Table A-3. Weather data. Wind speed at mobile weather stations 1974, mph. 26

Hour Interval Location Date 9-10 10-11 a-12 12-13 13-U. U-15 15-16 16-17 17-18 18-19

Finmoore July 29 2.01 1.66 Aug. 30 1.83 2.08 Sept. 1 3.45

Fort Fraser July 30 4.30

Lsrson's Aug. 26 Aug. 28 1.00 Sept. 2 0.84,

Greer Creek Sept. 3 0.76

Irvine s Aug. 29 1.23 27 Table A-3. Veather data. Humidity at mobile weather stations 1974, %.

Hour Internal Location Date 9-10 10-11 11-12 12-13 13-U U-15 15-16 16-17 17-18 18-19

Fimoore July 29 46 45 4-4 43 47 50 50 49 Aug. 30 67 61 51 47 50 5 1 5 0 49 Sept. 1 5 7 51 46 4-4 4-4 4-4

Fort Fraser July 30 48 48 b 5 43 41 39 37 36 43

Larrsonl s Aug. 26 83 82 81 76 75 Aug. 28 63 59 52 49 5 0 52 58 Sept. 2 58 5 5 5 5 53 50 48 46

Greer Creelc Sept. 3 61 59 5 2 4 5 43 41 42

Irvine s Aug. 29 67 63 58 55 5 2 51 4-4 37 Table A-3. Weather data. Barornetri.~pressure tit mobile weather atations 1974, "go 28

Hour Interval. Location Date 9-10- 10-11 11-12 12-13 13-3.4 3.4-15 15-16 16-17 17-18 18-19

Finmoore July 29 27.79 27.79 27.78 27.77 27.75 27.73 27.70 27.68 Aug. 30 27.88 27.88 27.88 27.87 27.84 27.81 27.79 27.77 Sept. 1 27.96 27.95 27.96 27.95 27.94 27.93

Fort fiaser July 30 27.62 27.62 27.62 27.62 27.02 27.62 27.61 27.60 27.60

Iarson' s Aug. 26 hug. 28 Sept. 2

Greer Creek Sept. 3 27.50 27.50 27.49 27.17 27.44 27.43 27*41

Irvinet s Aug. 29 27.62 27.62 27.62 27.62 29.62 27.61 27.59 27.59 Table A-3. Weather data. Incoming solar radiation at mobile weather stations

Hour Interval Location Date 9-10 10-11 11-12 12-13 13-14 14-15 15-16 16-17 17-18 18-19

Finmoore July 29 199.5 226.2 242.1 242.1 231.2 221.2 193.7 162.0 Aug. 30 U5.3 172.0 177.8 182.8 167.0 156.1 134.4 86.0 Sept. 1 177.8 193.7 199.5 193.7 162.0 145.3

Fort F'raser July 30 237.1 253.0 258.8 248.0 237.1 210.4 177.8 129.4 64.3 hrsonts Aug. 26 193.7 182.8 177.8 177.8 129.4 ~ug.23 199.5 199.5 199.5 172.0 123.6 134.8 86.0 Sept. 2 156.1 167.0 172.0 167.0 162.0 123.6 102.7 Greer Creek Sept. 3 167.0 187.8 191.5 193.7 182.8 134.4 102.7 Table A-3. Weather data. Incoming solar radiation at Fort Fraser weather 30 station 1975, Btu/sq f t/hr.

Hour July 18 July 19 July 20 July 21 July 22 July 23 July 24 July 25 July 26

Hour July 27 J'uly 23 July 29 July 30 3dy 31 Aug. 9. Aug. 2 Aug, 3 Atrg. L Table A-3. Continued. Weather data. Incoming solar radiation at Fort Fraser weather station 1975, Btu/sq ft/hr.

-,, Hour Aug. 5 Aug. 6 Aug.7 Aug.8 Aug.9 Aug.10 Aug.11 Aug.12 Aug.13

Hour Aug.14 Aug.15 Aug.16 Aug.17 Aug.18 Aug.19 Aug.20 Aug.21 Aug.22

0 17-14 34.7 LO. 5 69.4 133.0 115.7 69.1 75.2 69.L 57.8 40.5 11,6 0 0 Table A-3. Continued. Weather data. Incoming solar radiation at Fort FYaser weather station 1975, ~tu/sq ft/hr. 3 2

------Hour Sept.1 Sept.2 Sept.3 Sept.4 Sept.5 Sept.6 Septa7 Sept.8 Se~t.9

Hour Sept.10 Sept .11 Sept .?.2 S~pt.13 Sept .I4 Sept .l5 Sept -16 Sept. l? Sept -18

Hour Sept.19 0 Table 1 .Lher data. Air temperatures at Fort Fraser weather stations 1975, F. 33

Hour 7 , 8 duly 19 July 20 July 21 July 22 July 23 July 21, July 25 July 26

-- ~ ~p~~~~ - ~ -- ~~

. :,. J t $,, y " JU~Y23 JU~Y JUI~ AU;. I AU~.2 AU~. AU~. !!~:JI- . . .:,, 30 31 3 4 --". -,. , " . . . .- . . ...,-"=

; ,r , r?o-c'r : -a . . '. (1 C 17.O 4.8.0 54.0 56.0 lb7.5 L5.0 51.0 -, : ? ; 01-0 ' .., . ,~ ._., 47.5 ih.5 52.5 55.0 48.0 43.5 51.0 , . IJ:~,;?! '>ti +, ,) l~'.!,-.. 47.5 44.0 50.0 54.0 ~6.5 41.5 51.5 o?-:).- . . r . ', i .0 1+7.5 42.0 49.0 53.0 A5.5 40.0 51.5 ; "7 o!, o!, -(', : . ,!.. , t .q 47.5 4.0. 5 $8.5 51.5 46.0 38.5 52.0 05 -!:I ;; ,A,.at. i. /, Q. (3 47.5 i+.-./'i 0 49.0 51.0 $8.0 39.0 52.0 . ,. n(,-g:; ,? *I\! 53.0 50.0 L6.5 50.0 51.0 49.0 45.5 52.0 ,37-.:?3 ,: e (7 ?!v * : 51.5 50.0 52.0 52.5 50.5 46.0 52.5 , . r. c: 03-:1.. ,. j . (1) 53.5 .,..K . 0 55.0 5/+. 0 54.0 52.0 53.0 03-.~(; ~ ., 56.0 55.0 59.0 56.0 55.0 54. 5 56.0 54.0 I rr. 19-11 !. . ; !; 55.0 61.0 61.0 58.0 57 .O 59.0 56.5 . '. 11-1 r . . 56.0 56.0 63.0 63.5 59.0 59.5 58.0 60.0 1.2-1.' 5 '3 f,, 7.0 64.5 65.0 60.0 63.5 57.0 62.5 -?-I.:, ? i,.,.. .. ,'*-> ,,-t 59.0 65.5 67.5 62.0 56.5 56.5 63.0 l,lk-15 ,,.. B '5I .. 59 .o 66.5 63.0 61.5 60.0 57.0 62.0 . .. 1 r -1 f.. , . A; I t; '59 . (2 66.0 69.0 61.5 60.5 57.0 62.0 1~5-1>;j . ,',$., 7.. n 53.0 65.0 68.0 61.5 60.0 58 .O 59.0 17-1:: ;.,:'. 53.;. 60.0 63.5 67.0 61.0 58 0 57.0 58.0

,. '-3 (7 r 1 \< - .]. '.-I ..,. ., 53. f SO. 0 !3~.J 65.0 60.0 57.0 56.0 58.0 lr;-.? :! 'I *.I 511.9 56,. 5 61.0 53.0 56.5 56.5 55.0 57.0

,-':3 ... .-)1 ; 1; , r+ Z: . + I+'- . .., 55.0 57.0 53.0 54.0 52.0 53.0 76.0 ,. . '?I.-,,, ,- *

-- . ------Ho~r Aug. 5 Bug. 6 Aug. 7 Aug. 8 Aug. 9 Aug.10 Aug.11 Aug.12 Aug.13

C ., e I\. I, ., -.. d 'j'j:3 51 *' 52. 5 51.0 52.0 r7 C ii.. / 51.5 5Z.() 51.0 52.0 51.0 ,- .~. , 2 * 0 51.. C 52"5 52.5

!,3*0 5fL " 5 55.3 59.5 57.0 00.5 dO. O b? * 0 ' ,- el*2 $4.. 5 b.1. ,: 65.0 cz*;J. 65.5 52.0 64.5 52.5 Si. 0 61.. 5 63 .'3 51.. 5 51.0 zg (., 5s. 5 -'U. - ?I,*5 56.0 i '-7 2-7 ,c 53.0 5 " (.> 50c3 ;.'?. . . 5 &?lo Table A-3. Continuoed. Weather data. Air temperatures ~t Fort Fraser weather stations 1'175, F. - 2 Hour Au[;.?3 Aug.24 Aug.25 ~ug.26 Aug.27 Aug.28 Aug.29 Aug.30 Aug.31

Hour . .>t. :;i nt .3 Sc nt. 3 Sc?t .I, Sept. 5 Sept .6 Sept. 7 Sept .S Scpt. 3

. , L. 48.0 , .i , ., e ~. 44.5 i, L .,.. . * L5.5 ,. .. 1 -- i) 1L.O . .. I,.' .! 52.5 .,. i .O L.2.0 ., 5. c, L2.0 ) g .-, . ..:*..i 2.5 :- p, 1. L8. '7 r,K r -?.Ij . J >, -"; n 57.5 6 r .-- ,..I 58.0

4:. " ..\I 60.5 .:r:, / .O 61.0 ",. .. ..aj I, , ;. 61.5 ';O. i:, 61.0

< ( i-, 60.0 . I * L. 3.5 ., w. j6.5 ,. ., ,T, 'i'.\J 54. C

,; 'X i. i! 51.0 - ~,*~3 i' L?. 0

I \ A :, .r) 1,L. 5 .., - '., & I I. 47.0 Table A-3. Contimed. '+leather data, Air temperatures at Fort Fpsser weather stations 0 30 1975, F. Hour Sept .lO Sept. 11 Sept. 12 Sept. 13 Sept. U Sept. lS sept,16 Sept ,l7 Sept. 18

Hour Sop:. 19 Se;>t. ?;

Table A-3. 2ontinuaZ. 7'n:?rit,he 7 tirxtz. Buuidit-6 st E'~rtfizaer sesthcr ststion, 1975, 9. - -.-- 38 Hoar Aiig, 5 A..rg, 5 Azz, ? Aug. Z Aug* 9 u 1. S\ug..11 Asa6.:I?., Aug.13

C0-31. . - ?f. ",, < . 01-92 > 53 1 024): ~,<; 3 :j . . ', .- 03-0,: j ,: . . ,.. - CIf+-9 5 .. .., ,, i 2 ' . - pj-ij6 it,,! . .> 06-97 - % 93 /i , A 07-33 ' -!I .., . 55-01.> 91- . - 3 $> (3'7-? .3 , .* I.. u

. ~ 7 ,2--!3 8. .&. d..L )j fi , ". 1,.l- 2 ;:A 3 (] ,. ... a L I..? - -L 3 . ' .. -L 2-y~; ,. . 30 i.:- 1 71, ..I- 5-.; .:, '1::. ?.6-* I.. 7 >' -r; 7.;. ... ! -A. <. 70 r, :.- :j J. <-I 5 - 'I- :? ].:j-,:? 99 <: 33-:#3.L, .. . 35

-., 7 a i, -. L-22 37 :,, ;; - --3 1 , ., 07 ...,? '> - 1; li . -~ -. 39 Table A-3. Continued, Weather data. Humidity at Fort Fraser weather station 1975, $. 39

-- Hour Aug.23 Aug.21, Aug.25 Aug.26 Aug.27 Aug.28 Aug.29 AW.30 Aug.31 Table A-3. Continued. Weather data. Humidity at Fort baser weather station 1975, $. 40 ------Hour Sept. 10 Sept ,ll Sept .l2 Sept ,l3 Sept .U Sept.15 sept.16 Sept -17 Sept -18 Table A-3. Weather data. Barometric pressure and wind speed at Fort baser weather station, 1975.

Barometric Wind Barometric Wind Time Pressure Speed Wind Time Presswe Speed Wind PsT ' IILJ Date PST "HE;. mph Direction Date l~g• mph Direction

July 16 July 26

July 17

July 27

July 18

July 25

July 19

July 29

July 20

July 30

July 21.

July 31.

July ?L

Aug. i

July 23

July 2L

July 25 Table A-3. Continued. Weather data. Barometric presswe and wind speed at Fort kkaser weather station, 1975. 42

------Barometric Wind Barometric Vind Time Pressure Speed Wind Time Pressure Speed Wind Date PST clti go mph Direction Date PSI' 'I5g. mph Direction

Aug. 5 0800 1600 2000

Aug. 6 68'30 1200 Aug. 16 0830 1600 1200 2000 1400 2000 Aug. '; 0800 1200 1600 20a0

Aug. 8 0830 1200 Aug. 18 0300 I600 1200 2000 1500 2000 Aug. 9 0800 1200 160C 2000

Aug. 20 0800 2.200 160C 2000 Aug. li OSOG 1203 lGoo 200iS

bug. 22 0830 1200 1600 200C

Aug. 23 0715 120G 1600 2000 Table A-3. Continued. Weather data. Barometric pressure and wind speed at Fort Fraser weather station, 1975. 4 3 .- - - Barometric wind Barometric Wind Time Pressure Speed Wind Time Pressure Speed Jind

Date PST '1: t- 9 mph Direction Date PST "Hp, mnh Direction

Sept. 5 0800 1200 1600 W 2230 E

Sept. 6 0800 1200 1600 SE 2000

Sept. 7 091,5 1230 id N'd 1600 W IJW 203 0 iJ

Sept. 8 0730 !i' 1200 W SIJ 1600 Xr 2000 $I Aug. 29 0800 1900 170P W 2000

Aug. 30 0800 Sept. 10 0'730 1200 lib30 E 1600 2002 E 2000

Aug. "1 95:jO 1ZOO 1600 2000

Scpt. 1 0830 1100 1700 2230

Sept. 2 0800 1?00 1600 2000 W

Scpt. !+ 0300 1:?00 1000 ?300 Table A-3. Continued. Weather data. Barometric pressure and wind speed at Fort Fraser weather station, 1975.

Barometric Wind Time Pressure Speed Wind Date PST " Hg . mph Direction Table A-4. Phg ,sical cha racteristics of Nechako River, Cheslatta t,o Nautley rea.ch, from 1974 survey. A t discharge - 500 cfs. 'i!a ter 1.Iean n1ravel Dist. Cross- Depth 4.blne btw. Sec. 3u-f. btw. 3t.w. Ssc. Area Width Sec. Sec. Sec. (~i) (-, ft! (ft) (hums) 360 360 29 5 660 1775 335 275 42 5 2 50 325 310 530 64 5 620 3/10 570 390 640 390 300 5!+0 375 230 3 50 !+2 5 810 200 1110 130 600 800 300 24.5 .:;o i 'ji) 6 50 1 :?0 5 50 280 320 L+0 L!- 9 52 GO3 6,,5 8'0 ? ',0 730 6 50 225 14 5 200 I610 Table A-4. Physical characteristics of Nechako River, Cheslatta to Nautley 45 reach, from 1974 survey. At discharge 500 cfz. ',!nter ].lean n1ravel Dist. Cross- Depth 4.blne btw. Sec. 3u-f. btw. 5t.w. Sec. Area Width Sec. Sec. Sec. (~i) I-, ft! (ft) (ft) (kuiars) Table A-4. Continued. At discharge = 1500 cf's. Physical characteristics of Nechako River, Chesiatta to Nautley reach, from 1974 survey. 47

Water !.&an r,irave; Dist. Cross- Depth -7u-r.1e - btw. Sec, Sl.rf. btv. btw. Sec. Area Vidth Sec. Sec. Sec, (Xi ) (sq ft) (ft) ift) (:;ours j

3.25 2.83 i.;2 3 .I3 6-36 4 *35 ;.G7 9, L9 2-43 7.33 U -76 1-72 1.32 2.03 i.35 2.12 1 .:7 2.02 ;. ;3 2.19 3.7; 2-51 2.+5 3.47 i .5tt 2.77 - ,- u.-tl> 2.00 ;.;2 2 .GO . .53 2.72 ;.37 2.62 ;.a2 2.37 1 .s4 2.28 3 .'o9 3.70 ?. -- ,J . ,) r) 4.07 3 .jlj 3.33 13.52 3.48 2.55 3.30 .> .> . - 0.04 2.:> 3.3J 3.61 5-70 5.40 - -, J .u'r 4.63 2.27 3-72 3 -07 5.65 ;. 45 G.62 2.63 3.32 Ci 992 3.90 1.2; 2.32 3.67 3.10 m - u. 13 5 -33 J. 93 5-52 ? .72 3.81 i.35 L. A4 :-3s b .lB 1. it6 2. it, , -I 3 -62 L . LO 1 -4; 3 o!t 1.23 2.76 Ci -85 2.75 1.4: 3 -63 1. ;5 4.i.8 2 ./t6 3.67 i. 23 2.85 1 .G3 3.37 J.21 4.47 2 9134 0.52 1.62 6-16 3.67 3.46 Table A-4. Continued. At discharge = 2000 cfs. Physical characteristics of Nechako River, Cheslatta to ~e;tle~ reach, from 1-94survey.

Hean Travel - Dist. Cross- Depth +blma btw. Sec. Surf. btw btw. Sec. Area Uidth Sec. Sec. Sec. (~i*) - isq ft) (ft) (ft) (hoiirs) L1 690 2 690 3 610 . 4 1110 5 2000 6 67 5 7- 610 0 92 5 9 650 b 3 '-770 A' 1i 769 '3 A 4- l(?25 7 * -3 .4 l330 15 570 i6 850 ;7 7 50 i 6 ' C i? 9;O 550 Zij 980 2: 12"5 ? 2 122 5 2 3 1150 2 4 980 '2 i 1155 2 C 1420 27 1183 2 t; 1543 2 9 11?: 3-. ii 1173 3 L 1L7 5 -12 - 2220 2 3 ll00 3 4 860 3 5 575 3 6 1030 37 1690 3 6 97 5 39 710 4 3 6 50 G 1 '795 ir 2 75C I* 3 850 it ?OO 45 IC19.2 46 1210 :;-{ 12@ 4 5 rn>i; 4 9 I-,? < - .I. .,, - 71lC > G .l JL+J 5; 1625 52 1140 5 3 2260 5 4 ?LOO - . - Table A-4. Continued. At discharge = 3000 crs* Physical characteristics of Nechako River, Cheslatta to Nautley reach, from 1974 survey. .:ater 49 Xean ., -vel Dist. Cross- Depth

from 1950-52 survey. At 1000 s. 7. discharges = cf ,,'FLLL~ P'-,-_AAdve; 51 I4cor. . . Dist. Gcpth --wui.,re btw. -0 & bw. Siw. Sac. Sec. Sec. Sec. (Hi j (ft) i;;mrs j 52 Table 8-5. Continued. At diecharge = 2000 cfs. Physical characterietice of Nechako River, Nautley to Stuart reach, from 1950-52 eurvey. Water Mean Travel Diet. Crose- Depth the btw. Sec. Surf. btw. btw. Sec. Area Width Sec. Sec. Sec. (~i) (eq ft) (ft) I ft (hours) Table A-5. Continued. kt discharge-3000cp.;;, Physical characteristics of Nechako River, Nautley to Stuart reach from 1950-52 survey. . . !.2- 5 3 Nc3n Dist. CTO ss- Dcpth Stw. Scc. SET. btw. SCC. Z rca Ididtn Sec. Sac. (xi : (sq ft) (ft) ( ft ; 54 Table h-5. Continued. At discharge = 4000 cfs. Physical characteristics of .Nechako River, Che slatta to Nautley reach, from 1950-52 sumey, Uater Meak Tri~cl * - Dist. C1-oss- Depth ~lr,e btw. Sec. Surf. btq. Stw. sec. Area Uidth Sec. Sec. Sec. (Xi 1 (sq ft! (ft) (ft: (;lows) Table A-5. Continued. At discharge 5000 q,'i. Physical characteristics of Nechako River, Nautley to Stuart reach from 1950-52 survey. :;;: iE7 5 5 I4ean nj.-. river- .~- - Dlst. C;-oss- Gopth YA,,,O btw. Scc. .3~7f. btw. ;jtu. Sec. ;,;.ea b:'-j~th Sec. Ccc.'. ( j (sq ftj (ft) (ft j (;,uL~-s)

711 456 397 234 525 232 548 302 619 514 46 5 417 505 382 377 290 294 458 id2 731 400 489 312 5L? 576 ,970 153 38~ 29L ?42 ? 5? L+62 429 4 71, 'LO1 n-r 11' 542 572 688 ,55 r7c7& 3 61, 508 190 339 269 32 5 ?,?5 Table A&. Cal&ted water travel distance d mean depth for ho-b time intervals, Nechako River, CheaY~ttato Nautley reach. At diecharge = 500 cf 3.

Cumulative Mean Hour distance depth reach (Mi 1 (ft) Table A-6. Continued. Calculsted water travel distance and mean depth for hourly time intervals, Nechako River; Cheslatta to Nautley reach. At discharge = 500 cfs.

Cumulative Mea ri Pistances distance depth /LA:) (Mi1 (ft) 5 8 Table 1-6. Cmtinued. Calculated water travel distance and mean depth for hourly time intervals, Nechako River, Cheslatta to Nautley reach. At discharge =I000 cfs.

Cumulst ive Mean Hour Distance distance depth reach (Mi1 (Mi ) (fr.) 1.43 2.67 2.13 5.49 2 -68 10.18 3.72 5.15 5.34 1065 6.98 1.70 R -52 1-84 9.77 2.38 10.64 3-32 11.51 2-32 12.83 1 -92 L4.08 2.62 15.24 2.14 ib. 35 2.39 17-47 1.58 18-59 2 e 09 1%44 3.49 22-21 3.43 21.11 2-98 22 .a 1 3,06 22.73 2- 83 23-34 3-17 23.92 3.95 24.53 6,09 25.27 3.08 26 -113 2 -73 26.79 50 16 27.60 3 -55 28 -56 2.63 29.88 3.3d 3bt12 2q65 31.80 5.15 32-49 5 .:3G 23-72 4-12 35 -28 i -96 36.90 1.35 38.16 le$3 39-36 2 .50 40 -44 3-4-47 41 46 2-44 42.41 2 05.3 5-3. 19 2 -40 43-87 2.70 44-55. 3 -38 45.28 4.25 Table A-6. Continued. Calculated water travel distance and mean depth for hourly time intervals, Nechako River, Cheslatta to Nautley reach. At discharge = 1000 cfs.

Cumulative Mean Hour Distance distance depth reach (bii ) (Ni) ( i.+I u/i Table A-6. Continued. Calculated water travel distance and mean depth for 60 hourly time intervals, Nechako River, Cbeslatta to Hautley reach. At diecharge =1500 cfs.

Cumulative Hour Distance distance reach (Mi ) (Mi ) 1.73 1.73 0.76 2.49 1.L6 :3= 65 1.79 5 044 1.77 7-21 1-71 8 -93 1.29 10. ZL i -13 11-35 1.55 12.90 1.52 14 -42 1-41 15.83 1.35 17 18 1.36 18.54 1.04 14 -58 1.00 20.58 1-12 2l.71 0.96 22-67 0.8C 23 -48 3-75 24.23 0-87 25- LO

1. 0 0 1 26.11 3.9e 27-92

:6, 2 3 28.05 1. "35 29.40 1 e62 31.02 ii .90 31.92 1-12 33.04 1.57 34,hL ? -84 36 46 1-62 38.08 1-58 39.58 1.37 40,95 L.23 62.18 1.01 4.19 0.5s 44-99 0,93 45.31 1.00 46,O;

1 0 dC> 47;. i L 1. 0 48.20 1 *I? 49.37 1 90 5r3-3h a. 01, 5:,27 3 -76 52.G5 0.77 52 82 0 -71 53.53 Table A-6. Continued. Calculated water travel distance tind mean depth for hourly time intervals, Nechako Uver, Cheslatta to Nautley reach. 6 l At discharge = 1500 C~S-

Cumulative Mean Hour Distance distance dept !: rea :h (11i) (Mi) ( ft,) Table A-6. Continued. Calculated water travel distance end mean depth for hourly time intervals, Nechako River, Cheslatta to Nautley reach. 62 At discharge =2000 cfs.

Cum~lative Mean Hour Distance distance reach (Mi 1 ( .i 63 Table A-6. Continued. Calculated water travel distance and mean depth for hourly time intervals, Nechako River, Cheslatta to Nautley reach, At discharge =3000 cfs.

Cumulat ivc Xean distanze depth Distance (~i) (fi) (14i) Table A-6. Continued. Calculated water travel distance admean depth for 64 hourly time intervals, Nechako River, Cheslatta to Nautley reach. At discharge = 4mcf s.

Cumulative Mean Hour distznce depth reach (14j. ) \ft) Table A-7. Calculated water travel distance and mean depth for ho~lythe intervals, Nechako River, Nautley to Stuart reach. At discharge =lo00 cfs.

C?.mulnt i ve 1 :ea n Hour distance depth reach (Mi ) (ft) Table A-7. Continued. Calculated water travel distance and mean depth for hw~ly tifa8 intervals, Necha~ofiver, Nautley to Stuart reach. At discharge =I000 cfs. 66

Mean Hour reach Table A-7. C~atinued.. Calculated water travel distance and mean depth for hourly time intervals, Nechako River, Nautley to Stuart reach. 67 At discharge = 1000 cfs.

Cumul.ative Hour ii st,a.nc? reach (Mi) Table A-7. Continued. Calculated water travel distance and mean depth for hourly time,intervals, Nechako River, Nautley Stuart reach. , At discharge =2000 cfs.

Cumulative Mean Hour Distance i!is tance depth reach (Mi (~i) . (fi) Table A-7. Continued. Calculated water travel distance and mean depth for hourly time intervals, Nechako River, Nautley to Stuart reach. At ,discharge = 2000 cfs.

Cumulative Hour Distance distance reach (~i) (Mi) Table A-7- Continued. Calculated water travel distance aod me= depth for hourly'tirne intervals, lechako River, Hautley to Sbaar-b reach. 70 At. discharge =3(33~cfs.

Hour Distance reach (Mi ) Table A-7. Continued. Calculated water travel distance and mean depth for hourly time intervals, Nechako River, Nautley to Stuart reach. 7 1 At discharge =3000 cfs.

Curnula t i ve Mean Hour distance distance depth rach (Ki ) (Mi (fC) Table A-7. Continuedb Calculated water Itravel distance and mean depth for hourly time intervals, Hechako River, Xautley to Stuart reach. 72 At discharge = 4000 cfs.

C:urx.Lat Ivp Hour iii stance 42\ reach !A i]

t-70 3 e52 ;* .ca S,2S 4.19 c a56 Iskc* 3 m09 3-14 2 e51 S,C5 c.12 4,SG 2.85 2-55 2-89 3.4s i -92 c,ia '4 a15 see4 6.45 F,52 7,29 \ Ze3G i * 17 b ebb tetE 6 *55

B *GI a. 35 4 .t2 7. IS> 'T .3C de47 tr .il k, CCJ c *39 16,, &t: t e33 5 * .ff?i 5 .'I 5,:t 5 462 Table A-7. Continued. Calculated water travel distance and mean depth for hourly time intervals, Nechako River, Nautley to Stuart ~each. 73 At discharge = 5000 cfs.

Cumulative Hour Distance distance reach (ifi ) (~i) Table A-8. Hourly weather s- for Nechaico rive^ near Greer Creek, August 29-September 3, 1974. 7'A 7incORl~ Stst ion .krin3 Solar A 1.1- Hour Pressure Vei. Hm,i.Alty Y~~cii?:t,<.or: :i:e:T;q! a Date Interval !! IIg mph % jj.~,~,/:~~ft/hr p~L.

27-70 27.70 27.w 27,10 27.30 2'7.73 27.67 a?. 6r a?. 67 27.66 27.62 27.62 27.62 27,62 27.62 27.6i 27,39 27.59 27.& Z?, hO 27.6C 27.60 27. &3 27.60 2?. 7C 2'7,'73 29.79 27.70 27870 27.70 27.70 %?,?rj 27,7'; 27,70 27.69 27.68 17.67 27.65 27.693 27.60 ;27.58 27.5'7 17,hQ 27 ,(;0 27 .LC, 27,m 27.60 27.60 Table A-8. Continued.

Station Uind Hour Pr,QS sure Vel. Date Interval " Hg -mph 4.00 1.00 1.00 1.00 1-00 1.00 1.00 1.00 1.08 2 -16 3.25 2-93 2.61 3.47 4.33 5-11 6.05 4.60 3 15 2.42 2.20 2.00 1.80 1.60 1.40 1.20 1.00 0.80 0.60 0.30 1.00 0.83 1.66 2e49 2 -44 2-40 2 59 2.78 2 59 2.L1 1.86 1.26 1.52 1.78 1.80 1.80 1.70 1-70 Table A-8. Continued. 76 .- IncoE > . Station dind Soles .. -,.* ? Hour Pressure Vel. Hun;dity 9.~:dis,tfon Lmp* ft,/?<;= 0..r' Date Interval 8g zgi; % ats/sq Table A-9. Hourly weather summary for Nechako River near ~anderhoof, August 29-Sept,ember 3, 1974. Lnco:" Sta.ticn Viirld SoLar Air Iiour Pressure Vel Wumidity 3z.dlstion Tpp. Date Interval I' wg mph $ ~tu/s~i't/hr r Table A-9. Continued, 73 - Incorn, Station Wind S~j.ar .%: r 'LT Hour Pressure Vel. A,umidity 3. ,I:+.r:p. d Bt,r?,/ :qCi f.~,,/'lllT ;; Date Interval "Hg mph ,# Table A-9. Continued. Lnc:)irLe Stat j on vilnd Zcisr Air Hour ?r.essure 'Jel. Date Interval "Fig zph Table A-10. Theoretical maxim incoming eolar radktion at Fcrt >>.pozr latitude, July 24-August 18, Btu /eq f't/hr

* ,.., , .'. :; ,. .. '2 ' ' 2 TI :. 2. ., * -I" -I- ,,. ..:. !;G * .; !

'7 ?' .,, .,, ?:'.* ?: > ;.. ..<-,* ,,. C -. , '. , '. .. .- . ,., > .;,,-\ i-. , .

;; ;h' ::,? , ,... . , . < > :-: (I. ' - ~,.<, . .'%- .- ' - :

0 F Hour- July 29 August 10 00-01 57 .3 01-02 52.3 02-03 5.1.0 03-04 51 .? 04-05 55.5 05-06 60.5 06-07 68.5 07-08 78.0 08-09 s/*.3 09-10 G?. 5 10-11 a9.o 11-1; ?O. 5 13-i3 93.0 13-14 91.0 IL -1 4 90 .,3 15-16 81.0 16-17 86.5 17-13 8r7.5 13-1(] 7!,. . 5 19-20 "1.. 5 20-2-1 b?,lC: 21-22 65.C .22-33 60.3 ; .1 < 2 3 -:34 ! " ., ,*~.....I:. , .

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