Prev
S39 · E11 of 18 episodes
Next
Horizon

Horizon

1 year ago

Horizon

Killer Lakes #S39E11

7.4
Live 1h 74% 30
Horizon S39 E11 1964

Killer Lakes

Horizon  ·  Season 39, Episode 11

When Mount Nyiragongo erupted in the Democratic Republic of Congo in January 2002 it seemed like a disaster. Molten lava plunged down the hillside and poured into nearby Lake Kivu. Many died, and much of the city of Goma was destroyed. In fact, the local people were lucky. Had the eruption spread to one of the many volcanic faults under Lake Kivu, it could have unleashed one of the most terrifying of all natural phenomena - lake overturn. The phenomenon of lake overturn first struck in 1984 at Lake Monoun, in Cameroon. 37 people mysteriously died, suddenly and silently. A bizarre array of theories sprang up - secret testing of chemical weapons, a massacre by unknown terrorists; none really made sense. The scientists who looked into the disaster believed it had to be something to do with the lake itself, but they could not be absolutely sure. In 1986, before research into the Monoun disaster was made public, it all happened again. The tragedy of Lake Nyos, also in Cameroon, made headlines around the world when almost 1,800 people sleeping in houses around the lake suffocated in their sleep. The team of scientists that went to investigate concluded that carbon dioxide, trapped at the bottom of the lake, had suddenly risen to the surface, killing everything within 25km. They called their theory lake overturn. Eventually the scientists came to realise that carbon dioxide springs underground were pumping carbon dioxide into the lake and that the whole tragedy would be repeated if nothing was done. They installed an extraordinary fountain in the middle of the lake to help the gas disperse. Even so, the level of carbon dioxide in the waters remains a concern. The Nyos disaster promoted a survey of deep lakes in Africa and Indonesia to see where else lake overturn could happen. All seem to be safe, except one - Lake Kivu, in Rwanda. Lake Kivu is one of the largest and deepest lakes in Africa and two million people live around its shore. It is also filling up with carbon dioxide, although it's not yet saturated with the deadly gas. The only thing that could trigger a gas release would be a massive geological event. Worryingly, Lake Kivu is sitting in an earthquake zone and surrounded by active volcanoes, including Mount Nyiragongo. If an eruption or an earthquake was to happen under the lake, then the effect could release millions of tons of asphyxiating gas into the surrounding areas. Until a solution is found, millions of lives could be at risk.


Episode 11 of Season 39 from Horizon — available to stream in HD on any device.

Released
04 Feb, 1964
Jump to

Comments & Discussions

Join Discussions
0 comments

Join the conversation

Sign in to leave a comment

Log in

No comments yet

Be the first to share your thoughts!

Recommended

Because you liked Horizon

01
Killer Confessions: Case Files of a Texas Ranger
S01·E05 HDTV
2026

Killer Confessions: Case Files of a Texas Ranger

Killer Confessions: Case Files of a Texas Ranger

3mos ago TV
02
Just a Dash
S03·E01 HDTV
2019

Just a Dash

Just a Dash

4mos ago TV
03
NOVA
S53·E04 HDTV
1974

NOVA

NOVA

3mos ago TV
04
The BMF Documentary: Blowing Money Fast
S02·E06 HDTV
2022

The BMF Documentary: Blowing Money Fast

The BMF Documentary: Blowing Money Fast

3mos ago TV
05
Mission to Space with Francis Bourgeois
S01·E01 HDTV
2026

Mission to Space with Francis Bourgeois

Mission to Space with Francis Bourgeois

4mos ago TV
06
Spring Break Murders
S02·E03 HDTV
2025

Spring Break Murders

Spring Break Murders

4mos ago TV
07
The Hillside Strangler
S01·E04 HDTV
2026

The Hillside Strangler

The Hillside Strangler

4mos ago TV
08
Take That
S01·E03 HDTV
2026

Take That

Take That

4mos ago TV
09
History's Deadliest with Ving Rhames
S01·E08 HDTV
2026

History's Deadliest with Ving Rhames

History's Deadliest with Ving Rhames

2mos ago TV
10
Body in the Water
S01·E10 HDTV
2025

Body in the Water

Body in the Water

3mos ago TV
Swipe to explore

Explore Content