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

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.


1983 ◽  
Vol 40 (7) ◽  
pp. 1142-1167 ◽  
Author(s):  
Michael Waldichuk

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.



1957 ◽  
Vol 14 (4) ◽  
pp. 521-552 ◽  
Author(s):  
Joseph Eugène Henri Légaré

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.



1991 ◽  
Vol 18 (3) ◽  
pp. 465-471 ◽  
Author(s):  
Otto J. Svec ◽  
A. O. Abd El Halim

A prototype of a new asphalt compactor termed "asphalt multi-integrated roller (AMIR)" was built as a joint venture between the National Research Council of Canada (NRC) and a Canadian manufacturer, Lovat Tunnel Equipment, Inc. The purpose of this project was to prove this new compaction concept in a full-scale environment. This paper describes one of the field trials carried out on the campus of the NRC and reports the results quantifying the quality of the AMIR compaction. Key words: compactor, asphalt mix, field trials, laboratory testing.



1988 ◽  
Vol 15 (4) ◽  
pp. 547-552
Author(s):  
Y. L. Lau

Experiments using artificial dunes show that the friction factor is reduced when the steep face of the dune is on the upstream side, i.e., when the direction is reverse that of normal. Calculations using bedform regime relationships show that this configuration of reverse flow over dune profiles could have existed in the Pitt River, causing the decrease in bed roughness which was found during the calibration runs. Key words: friction factor, dunes, tidal flow, Fraser River, bedform roughness, Pitt River.



1954 ◽  
Vol 11 (5) ◽  
pp. 501-506
Author(s):  
W. E. Barraclough ◽  
M. Waldichuk

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.



1985 ◽  
Vol 42 (12) ◽  
pp. 2020-2028 ◽  
Author(s):  
Eric B. Taylor ◽  
J. D. McPhail

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.



1988 ◽  
Vol 15 (4) ◽  
pp. 633-643 ◽  
Author(s):  
Ian Smith ◽  
Luke R. J. Whale ◽  
Colin Anderson ◽  
Barry O. Hilson ◽  
Peter D. Rodd

This paper summarizes the output from a long-term project commenced in 1980 with the objective of providing reliable knowledge of the mechanical properties of nailed or bolted joints subjected to short-term lateral loadings. Motivation was the development on an international basis of probability-based partial coefficients limit states design codes for structural timberwork. Comparisons are presented between design solutions produced by applying this research and those by the use of contemporary "soft conversion" international partial coefficients limit states design codes that were calibrated from previously available data. Differences relate primarily to design of bolted joints. It is shown that there is an established acceptance in Canada of the approach adopted. Key words: wood, joints, nails, bolts, design.



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