Coquitlam Lake

Coquitlam Lake
Coquitlam Lake
	Coquitlam Lake
Location	North of Coquitlam, British Columbia
Coordinates	49°24′N 122°47′W / 49.400°N 122.783°W
Type	Reservoir
Primary inflows	Coquitlam River
Primary outflows	Coquitlam River
Basin countries	Canada
Surface area	11 km2 (4.2 sq mi)
Surface elevation	154 m (505 ft)
Islands	Coquitlam Island

Coquitlam Lake is a reservoir located just north of Coquitlam, British Columbia. It is one of the three main water sources for Metro Vancouver, and part of the Coquitlam watershed. It is also a part of BC Hydro's power generation system. A tunnel directs water from the lake to nearby Buntzen Lake, and from there to a pair of power stations.^[1]

History

Construction of the tunnel between Coquitlam Lake and Buntzen Lake began in 1902 and finished in 1905, supplying water to powerhouses on Indian Arm, which supplied electricity to Vancouver.^[2]

The first Coquitlam Dam, built to raise the water level by 5 feet (1.52 m), was begun in April 1904 and completed in 1905. It was built to protect the water supply to the powerhouses, and also supplied water to New Westminster.^[2] By 1906 the original dam was discovered to be leaking, and while repairs were made the leak continued through 1908, until the current dam was completed in 1914.

There is a glacier in the watershed of the reservoir, Coquitlam Glacier, which is the only glacier in Metro Vancouver. It formed during the Little Ice Age and is shrinking as the last Ice Age ends and, potentially, due to the effects of climate change. It is expected to melt by 2050.^[3]

Climate

Climate data for Coquitlam Lake
Month	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	Year
Record high °C (°F)	13.3 (55.9)	14.4 (57.9)	21.1 (70.0)	26.1 (79.0)	32.8 (91.0)	33.3 (91.9)	36.7 (98.1)	34.4 (93.9)	31.7 (89.1)	25.0 (77.0)	18.9 (66.0)	13.3 (55.9)	36.7 (98.1)
Mean daily maximum °C (°F)	2.7 (36.9)	5.1 (41.2)	7.1 (44.8)	11.5 (52.7)	15.9 (60.6)	18.5 (65.3)	22.0 (71.6)	21.3 (70.3)	18.1 (64.6)	12.7 (54.9)	7.1 (44.8)	4.3 (39.7)	12.2 (54.0)
Daily mean °C (°F)	0.6 (33.1)	2.5 (36.5)	3.7 (38.7)	7.0 (44.6)	10.9 (51.6)	13.7 (56.7)	16.6 (61.9)	16.3 (61.3)	13.6 (56.5)	9.2 (48.6)	4.5 (40.1)	2.2 (36.0)	8.4 (47.1)
Mean daily minimum °C (°F)	−1.5 (29.3)	−0.1 (31.8)	0.3 (32.5)	2.6 (36.7)	5.9 (42.6)	8.9 (48.0)	11.1 (52.0)	11.2 (52.2)	9.0 (48.2)	5.6 (42.1)	2.0 (35.6)	0.1 (32.2)	4.6 (40.3)
Record low °C (°F)	−21.1 (−6.0)	−16.7 (1.9)	−12.2 (10.0)	−5.6 (21.9)	−2.2 (28.0)	1.7 (35.1)	3.3 (37.9)	4.4 (39.9)	−0.6 (30.9)	−5.0 (23.0)	−17.8 (0.0)	−22.8 (−9.0)	−22.8 (−9.0)
Average precipitation mm (inches)	508.0 (20.00)	397.8 (15.66)	350.4 (13.80)	237.4 (9.35)	140.5 (5.53)	130.9 (5.15)	86.4 (3.40)	108.2 (4.26)	204.4 (8.05)	403.0 (15.87)	480.6 (18.92)	568.4 (22.38)	3,616 (142.37)
Average snowfall cm (inches)	62.6 (24.6)	23.2 (9.1)	15.9 (6.3)	1.0 (0.4)	0.0 (0.0)	0.0 (0.0)	0.0 (0.0)	0.0 (0.0)	0.0 (0.0)	0.0 (0.0)	6.3 (2.5)	39.2 (15.4)	148.2 (58.3)
Average precipitation days	21	18	19	17	13	13	8	11	13	19	21	22	195
Average snowy days	6	3	2	0	0	0	0	0	0	0	1	4	16
Source: Environment and Climate Change Canada^[4]^[5]