scholarly journals Estimating Exposure of Interior Fraser River Steelhead to Strait of Georgia and Fraser River Commercial Fisheries from 2004–2016

2018 ◽  
Keyword(s):  
Commercial Fisheries ◽  
Fraser River ◽  
Strait Of Georgia

The Qualitative and Quantitative Distribution of Plankton in the Strait of Georgia in Relation to Certain Oceanographic Factors

1957 ◽  
Vol 14 (4) ◽  
pp. 521-552 ◽  
Author(s):  
Joseph Eugène Henri Légaré
Keyword(s):  
Salinity Gradient ◽  
General Distribution ◽  
Fraser River ◽  
Strait Of Georgia ◽  
Quantitative Distribution ◽  
Qualitative And Quantitative ◽  
Chemical Factors ◽  
Physical And Chemical ◽  
Plankton Communities ◽  
Made In

In order to gain some picture of the seasonal variations in the plankton communities two cruises were made in the Strait of Georgia, one in June 1955, and the other in November 1955; 165 plankton collections were taken, also surface temperatures.The correlation of these data have resulted in a number of conclusions concerning the distribution of plankton in the Strait of Georgia. The chief factor affecting the general distribution of plankton is the salinity gradient. The inflow of fresh water from the Fraser River forms zones of varying properties, and leads to the development of different plankton communities. The extent to which physical and chemical factors may determine the presence or absence of certain organisms from the zones described is discussed.

Construction of the Iona Outfall submarine section

1990 ◽  
Vol 17 (1) ◽  
pp. 113-118 ◽  
Author(s):  
T. W. Lively ◽  
C. D. Gowe ◽  
H. R. Woodhead
Keyword(s):  
Key Words ◽  
Joint Venture ◽  
Sewage Treatment ◽  
Bolted Joints ◽  
Fraser River ◽  
Strait Of Georgia ◽  
Alternative Method

In February 1987, the Greater Vancouver Sewerage and Drainage District awarded an $8.5 million contract for the construction of the Iona Outfall submarine section. The contract awarded to the Dillingham–Manson joint venture involved the installation of approximately 3200 m of twin 2.3 m diameter steel outfall, of which 500 m was twin 2.1, 1.8, and 1.4 m diameter steel diffuser sections. The outfall extended from the end of the Iona Jetty into the Strait of Georgia near the mouth of the Fraser River and was 107 m deep at the end of the diffuser. The tender documents suggested a method of installation such that the entire twin outfall pipe was fabricated on an existing jetty complete with flotation pipe and pulled into the water. The contractor submitted an alternative method with the tender and was the successful low bidder. The proposed installation method was to assemble the pipe into nominal 300 m lengths in Dillingham's North Vancouver yard, launch them, tow them to the site, and sink and bolt them together underwater. This paper discusses the more interesting aspects of the project. Key words: construction, pipelines, robotics, sewage treatment, bolted joints.

Pollution in the Strait of Georgia: a Review

1983 ◽  
Vol 40 (7) ◽  
pp. 1142-1167 ◽  
Author(s):  
Michael Waldichuk
Keyword(s):  
Urban Communities ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
River Estuary ◽  
Oxygen Depletion ◽  
Fraser River ◽  
Pulp Mills ◽  
Strait Of Georgia ◽  
Spring Freshet

The Strait of Georgia, when considered as a whole, is still comparatively free of major pollution problems. Local environmental degradation has taken place, however, in waters on the periphery of the Strait, adjacent to urban communities and industries, such as pulp mills. The Fraser River, which is the major source of freshwater to the Strait, introduces natural and man-made materials that can adversely affect its estuary and the marine environment. The Strait of Georgia is flushed regularly, with deep waters being replaced about annually and waters in the upper layer having a considerably shorter residence time. Buildup of pollutants or their effects, e.g. oxygen depletion, are prevented in this way. However, there is refluxing of surface waters into the deep zone from the mixing region at the southern entrance to the Strait, and this means that surface pollutants such as oil could pollute the deep water and be retained there for up to a year. Problems affecting fisheries have been identified at the Fraser River Estuary arising from discharge of sewage treatment plant effluent. The major problem of pollution affecting fisheries in the Strait of Georgia has been bacteriological contamination from sewage, which has necessitated the closure of shellfish beds. The quality of oysters, as represented by condition factor and flavor, has deteriorated in the vicinity of some pulp mills. Evidence so far indicates that the "critical pollutants," e.g. petroleum hydrocarbons, organochlorines, and metals, which are persistent, toxic, and can be bioaccumulated by marine organisms, are present in low concentrations in the water, sediments, and biota away from the Fraser River Estuary. Wood wastes in the Strait of Georgia create a menace to navigation, especially during the spring freshet of the Fraser River.

Offshore Characteristics in the Deep Waters of the Strait of Georgia as Indicated by Bathypelagic Fish

1954 ◽  
Vol 11 (5) ◽  
pp. 501-506
Author(s):  
W. E. Barraclough ◽  
M. Waldichuk
Keyword(s):  
Deep Water ◽  
Fraser River ◽  
Strait Of Georgia ◽  
Deep Waters ◽  
Juan De Fuca ◽  
Bottom Waters ◽  
Chemical Conditions ◽  
Physical And Chemical ◽  
Juan De Fuca Strait ◽  
Inflowing Water

An attempt is made from oceanographical observations to explain the occurrence of certain bathypelagic species of fish which have been captured in the bottom waters of the southern Strait of Georgia. It is noted that there is a considerable seaward surface Sow of water from the Fraser River. The water from intermediate depths over the continental shelf forms the inflowing deep water of Juan de Fuca Strait mixing with the Fraser River water in the turbulent channels of the San Juan Archipelago. This mixture forms the deep inflowing water of southern Strait of Georgia and the outflowing surface water of the Juan de Fuca Strait as shown by salinity distribution and current measurements. The net inward movement of deep water is suggested as an agent of transport or a directive factor for the occurrence of these fish in this region. Physical and chemical conditions of the deep water in the Strait of Georgia are shown to be only slightly different from those found in the intermediate offshore water. It is probable that a combination of factors provides conditions suitable for survival of these species in the deep water of the southern Strait of Georgia.

Variation in Body Morphology Among British Columbia Populations of Coho Salmon, Oncorhynchus kisutch

1985 ◽  
Vol 42 (12) ◽  
pp. 2020-2028 ◽  
Author(s):  
Eric B. Taylor ◽  
J. D. McPhail
Keyword(s):  
British Columbia ◽  
Coho Salmon ◽  
Function Analysis ◽  
Oncorhynchus Kisutch ◽  
Fraser River ◽  
Strait Of Georgia ◽  
Coastal Streams ◽  
Morphological Differences ◽  
Median Fins ◽  
Coastal British Columbia

Ten populations of juvenile coho salmon, Oncorhynchus kisutch, from streams tributary to the upper Fraser River, the lower Fraser River, and the Strait of Georgia region were morphologically compared. Juveniles from coastal streams (Fraser River below Hell's Gate and the Strait of Georgia) were more robust (deeper bodies and caudal peduncles, shorter heads, and larger median fins) than interior Juveniles. Discriminant function analysis indicated that juvenile coho could be identified as to river of origin with 71% accuracy. Juvenile coho from coastal streams were less successfully classified as to stream of origin; however, juveniles could be successfully identified as either coastal or interior with 93% accuracy. Juvenile coho from north coastal British Columbia, Alaska, and the upper Columbia system also fitted this coastal and interior grouping. This suggests that a coastwide coastal–interior dichotomy in juvenile body form exists. Three populations (one interior and two coastal) were studied in more detail. In these populations the coastal versus interior morphology was consistent over successive years, and was also displayed in individuals reared from eggs in the laboratory. Adult coho salmon also showed some of the coastal–interior morphological differences exhibited by juveniles. We concluded that the morphological differences between coastal and interior coho salmon are at least partially inherited.

Sedimentary environments and postglacial history of the Fraser Delta and lower Fraser Valley, British Columbia

1983 ◽  
Vol 20 (8) ◽  
pp. 1314-1326 ◽  
Author(s):  
John J. Clague ◽  
John L. Luternauer ◽  
Richard J. Hebda
Keyword(s):  
British Columbia ◽  
Lacustrine Sediments ◽  
Fraser River ◽  
Large Area ◽  
Borehole Data ◽  
Strait Of Georgia ◽  
Sea Levels ◽  
The Holocene ◽  
Sedimentary Environments ◽  
Channel Deposits

The Fraser River delta, which is about 1000 km2 in area above low tide level, has been built into the Strait of Georgia in southwestern British Columbia during the Holocene. Present-day sedimentary environments, including foreslope, tidal flat, river channel, floodplain, and bog, also existed earlier during the delta's development. Borehole data reveal a succession of sedimentary environments related to Holocene progradation of the delta south and west of New Westminster. At each site, marine basin and distal foreslope sediments are overlain by proximal foreslope materials, which in turn are overlain by coarser intertidal platform and channel deposits capped by floodplain and bog sediments.Initial growth of the Fraser Delta was preceded both by deglaciation of the region and by the rapid westward extension of the Fraser River floodplain down a partially submerged, glacially scoured trough east of New Westminster. Irregularities on the trough floor were covered by fluvial, deltaic, marine, and lacustrine sediments as the floodplain extended westward. About 10 000 years ago, the Fraser River began to empty directly into the Strait of Georgia through a gap in the Pleistocene uplands at New Westminster. A delta was constructed south and west from this site as the sea dropped below its present level relative to the land. Deltaic progradation continued after sea level stabilized at about −12 m elevation after 8000 years BP. A marine transgression between 7000–7500 and 5000–5500 years ago inundated parts of the Fraser proto-delta and temporarily inhibited its seaward advance. This transgression ended with the sea perhaps 1 or 2 m below its present position, whereupon a large area of the delta became emergent and large bogs began to form. During the remainder of the Holocene, the Fraser Delta grew westward, but apparently not southward, under a regime of relatively stable sea levels.

Salt and Freshwater Exchange on Roberts Bank, British Columbia

1988 ◽  
Vol 23 (1) ◽  
pp. 160-178 ◽  
Author(s):  
P.B. Crean ◽  
T.S. Murty ◽  
J.A. Stronach
Keyword(s):  
Fresh Water ◽  
Seasonal Changes ◽  
River Discharge ◽  
Retaining Wall ◽  
Surface Currents ◽  
Fraser River ◽  
Strait Of Georgia ◽  
Shallow Layer ◽  
Layer Flow ◽  
Incoming Tide

Abstract One of the aspects of the seaward movement of fresh water from the Fraser River is its passage tangential to Roberts Bank and subsequent recirculation onto the bank. A synoptic study of the oceanography of the bank is described, part, of a larger study of surface currents in the Strait of Georgia. Seasonal changes in salinity and temperature over Roberts Bank are presented. The freshwater flows and motions of the salt wedges in the river and on the bank are described. Under the restraints of a retaining wall immediately north of the river, and on the incoming tide, a shallow layer of fresh water briefly forms an eddy, varying in size with river discharge and extending over the bank to the south. The influence of the two-layer flow on sedimentation is also discussed.

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