Garibaldi Lake

In this problem, we learned about Garibaldi Lake (a lake near Squamish) and the Barrier that dams the lake. We were asked what would happen if we have a natural disaster such as an earthquake or faulting that would cause this barrier to move or collapse.

The questions were “How much water does the Barrier contain? If the Barrier faulted, what would happen? How much water would escape, and how much power is the escaping water equivalent to?”

Here are some numbers about Garibaldi Lake and the Barrier:

Garibaldi Lake –

Surface area: 9.94km2

Average depth: 119m

Max. depth: 258.7m

The Barrier –

Height: 243m

Length: 2.4km

https://en.wikipedia.org/wiki/Garibaldi_Lake

https://en.wikipedia.org/wiki/The_Barrier

We first started off by finding the approximate volume of the lake. We decided to use the formula for a rectangular prism to find the volume, because we used the average depth which might make it more accurate about the depth for the whole lake.

Then I converted in to kilograms, to find the approximate weight of the lake.

This is equivalent to the weight of 60 million cargo ships, 6.5 million blue whales, or 21.5 million Leaning Towers of Pisa.

If the barrier faulted, the water will drain until the fault line and lake even out. This means not all the water in the lake will escape. I know this because the water levels in the lake don’t reach the very top of the barrier, and the barrier isn’t tall enough to reach the very bottom of the lake. This means that the water would, at the most, only drain to where the barrier stops but the lake continues to descend.

Even though not all the water will drain out, it will still be enough and powerful enough to reach and ruin the closest towns, one of them being Squamish.

It’s a scary thought, but with a very high chance of an earthquake in this area, the barrier may actually break one day. This lake has a ton of water in it and it can cause a lot of damage if it escapes, so lets hope one day this possibility is never a reality.