153:. The crossing is remarkable, for being first implemented as an overhead crossing, and then later replaced by a cable tunnel. Hydro-Québec wanted to complete the transmission line in time, which was only possible with an overhead crossing of Saint Lawrence River. However, due to the negative visual impact of the large towers of the overhead crossing on the local populations of Grondines and Lotbinière, it was decided to build a cable tunnel under the river, although this made the project more expensive.
22:
170:
were erected. The suspension pylons on each side of the waterway were 140 meters (459 ft) tall to ensure the required clearance. Building these towers required five months construction time and approximately 40 specially trained workers. At the end of 1989 the overhead crossing, which consisted
183:
In spring 1989 work on the 3,954 metres (12,972 ft) long cable tunnel started, which took six months of drilling in two 12-hour shifts. The average drilling rate was 27 metres (89 ft) a day, but achieved in horizontal sections over 90 metres (300 ft) a day. On March 26, 1990, the
188:
reached the surface 8 centimetres (3.1 in) away from its target point. Later the tunnel was covered with concrete, and troughs for the cable support were installed. On
November 1, 1990, the underground HVDC transmission line went in service with a transmission rate of 1200 MW, which was
165:
to the mainland as construction for the pylons of the overhead crossing started. Between July 1988 and spring 1989, 20,000 truck loads of 400,000 tonnes (390,000 long tons; 440,000 short tons) were transported. In 1989 the towers of the temporary
192:
In 1992 the overhead line over the Saint
Lawrence River, including the artificial islands and the jetties were dismantled. Portions of one of these towers would later be used as part of the observation tower at
171:
of five towers, was completed. After the tunnel was completed the overhead line and pylons used for it were dismantled. One of the pylons would later be used for the construction of the
39:
271:
315:
86:
219:
58:
65:
345:
72:
350:
54:
244:
360:
79:
340:
325:
224:
127:
105:
335:
138:
43:
161:
In 1988 construction work for three artificial islands in the Saint
Lawrence River, which were connected with
330:
195:
172:
258:
310:
355:
320:
32:
167:
185:
142:
245:"Pylons of the Saint Lawrence River HVDC Powerline Crossing (Deschambault-Grondines, 1989)"
134:
8:
205:
123:
304:
286:
273:
200:
21:
150:
146:
162:
130:
178:
46:. Unsourced material may be challenged and removed.
259:"Cité de l'Énergie Observation Tower (Shawinigan)"
156:
302:
220:Hydro-Québec's electricity transmission system
133:transmission line over (and later, under) the
55:"Saint Lawrence River HVDC Powerline Crossing"
316:Electric power transmission systems in Canada
120:Saint Lawrence River HVDC Powerline Crossing
106:Learn how and when to remove this message
346:Electric power infrastructure in Canada
303:
189:increased to 2250 MW on July 1, 1991.
44:adding citations to reliable sources
15:
13:
351:Buildings and structures in Quebec
14:
372:
225:Quebec - New England Transmission
179:Underground crossing construction
203:. The costs for dismantling was
20:
31:needs additional citations for
251:
237:
157:Overhead crossing construction
1:
361:1991 establishments in Quebec
230:
7:
213:
10:
377:
341:Tunnels completed in 1991
326:Powerline river crossings
336:HVDC transmission lines
287:46.606056°N 71.989111°W
168:overhead line crossing
292:46.606056; -71.989111
186:tunnel boring machine
331:Saint Lawrence River
196:La Cité de l'Énergie
173:La Cité de l'Énergie
135:Saint Lawrence River
40:improve this article
283: /
175:observation tower.
122:is the crossing of
128:Quebec-New England
311:Tunnels in Canada
116:
115:
108:
90:
368:
356:Energy in Quebec
298:
297:
295:
294:
293:
288:
284:
281:
280:
279:
276:
263:
262:
255:
249:
248:
241:
209:
111:
104:
100:
97:
91:
89:
48:
24:
16:
376:
375:
371:
370:
369:
367:
366:
365:
301:
300:
291:
289:
285:
282:
277:
274:
272:
270:
269:
267:
266:
257:
256:
252:
243:
242:
238:
233:
216:
204:
181:
159:
112:
101:
95:
92:
49:
47:
37:
25:
12:
11:
5:
374:
364:
363:
358:
353:
348:
343:
338:
333:
328:
323:
318:
313:
265:
264:
250:
235:
234:
232:
229:
228:
227:
222:
215:
212:
180:
177:
158:
155:
114:
113:
28:
26:
19:
9:
6:
4:
3:
2:
373:
362:
359:
357:
354:
352:
349:
347:
344:
342:
339:
337:
334:
332:
329:
327:
324:
322:
319:
317:
314:
312:
309:
308:
306:
299:
296:
260:
254:
246:
240:
236:
226:
223:
221:
218:
217:
211:
207:
202:
198:
197:
190:
187:
176:
174:
169:
164:
154:
152:
148:
144:
140:
136:
132:
129:
125:
121:
110:
107:
99:
88:
85:
81:
78:
74:
71:
67:
64:
60:
57: –
56:
52:
51:Find sources:
45:
41:
35:
34:
29:This article
27:
23:
18:
17:
321:Hydro-Québec
278:71°59′20.8″W
275:46°36′21.8″N
268:
253:
239:
194:
191:
182:
160:
124:Hydro-Québec
119:
117:
102:
96:January 2021
93:
83:
76:
69:
62:
50:
38:Please help
33:verification
30:
290: /
305:Categories
231:References
208:16 million
201:Shawinigan
143:Lotbinière
66:newspapers
139:Grondines
214:See also
137:between
163:jetties
80:scholar
151:Canada
147:Quebec
82:
75:
68:
61:
53:
87:JSTOR
73:books
206:CA$
141:and
131:HVDC
118:The
59:news
199:in
126:'s
42:by
307::
210:.
149:,
145:,
261:.
247:.
109:)
103:(
98:)
94:(
84:·
77:·
70:·
63:·
36:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.