23 December 2010
Reports of landslides in California and Colombia
Posted by Dave Petley
News reports coming out of Colombia this morning suggest that there has been yet another large landslide in that battered country. Colombia Reports is carrying a story that a landslide occurred yesterday in Santander Province in the north of the country. The landslide is reported to have struck a small hamlet between Rionegro and El Playon, destroying the a number of houses and reportedly burying 20 people. There’s not much news on this at the moment; hopefully more will emerge during the day.
Meanwhile, on the day that I finally left California yet another “Pineapple Express” rainstorm blew in, triggering floods and landslides across a wide area. I have been trying to collate a list of reported landslides:
- La Conchita: This is probably the most infamous landslide site in recent years in the US, having been the site of two very large landslides in 1995 and then 2005. A further slide occurred here yesterday, not as large as the earlier events, but still substantial. The Daily Sound reports that the landslide was shallow but had a surface area of 12,000 square feet (about 1,100 square metres), whilst the Los Angeles Times reports that a geologist brought in to investigate the site has stated that the landslide is likely to move further. The Google Earth image below, taken before the slide yesterday, demonstrates clearly why there is such concern about this site:
- Green Valley Lake in San Bernadino has reportedly suffered from mudslides that have blocked the access roads, effectively isolating the community.
- Another landslide reportedly blocked a feeder road for Interstate Highway 10 at the transition to State Route 57 in the Pomona area, blocking three lanes of the road.
- The town of Highland in San Bernadino County has reportedly been hit by one or more mudslides, damaging 20 houses and burying many cars.
There are many others I’m sure. Please add more in comments and I’ll try to update the page.
There are some shots of people’s yards in this video.
This one has the house in Arizona crashing into the river.
What also appears to be a land sliding event in North Santander/Colombia caused the entire population (3000-4000 people) of the town Gramalote to be completely evacuated.
http://www.eltiempo.com/colombia/oriente/alerta-por-alud-en-gramalote-norte-de-santander_8623741-4 (both in Spanish, use Google translate)
Houses are just cracking and falling apart the same as roads. The whole ground appears to be moving. This has started on the 19 Dec. but apparently people have been warned as many already left before that date. So far no deaths have been reported but many lost their homes and belongings and are housed in temporary shelters. All roads to the town are closed now and access is prohibited.
Gramalote is located on the eastern cordillera of the Andes, within a heavily broken, rugged, mountainous area. It is said to be built across a fault line. There have been warnings of further landslides, avalanches, floodings.
Relating to Dr. Dave’s article above:
“Rescue workers found 15 of 20 persons who were feared dead after a landslide buried their homes in the north of Colombia on Thursday.”
As I wanted to see when and how the Gramalote disaster began I have compiled a little history of news reports. They are all from the news site “Caracol Radio”, translated with Giggle and some of the outcome edited. Some are audio features where I got only head lines. For some translations I used a dictionary to get a better understanding. I hope I got most of it right. All can be read in original with photos and audios here:
01 Oct., 14 Nov., 28 Nov., 11 Dec. Gramalote is among the [many] towns warned by the Government to be most threatened by heavy rainfalls > landslides. In the latest of these reports Gramalote is one of the places with highest risk of landslides.
17 Dec. The first 100 families have been evacuated due to an alert of “una avalancha”. Logistical support is said do be provided. Inhabitants panic. One reader’s comment mentions “a crack in one of the hills bordering gramalote and is becoming more pronounced”.
[The evacuation must have been going on at full speed because:]
18 Dec. Gramalote emergency: About 150 homes have collapsed. Over a hundred people remain in the urban population. Residents refuse to leave Gramalote without their belongings.
18 Dec. Gramalote will probably disappear in a few hours said Minister of the Interior. He explained that the land from the top of the hill is coming down and the movement on the ground has led to the houses to crack and go dropping one after another.
19 Dec. Faced with the geological fault, the landslide movement and the breaking of the roads in the area, authorities closed the roads [into Gramalote]. Ombudsman confirmed that the road to Gramalote via the municipality of Santiago was fully cracked, leaving the town completely isolated, because the other axis road that communicated with Sardinata has been blocked for several days by landslides. Residents are discouraged from re-entering the town to retrieve belongings.
19 Dec. Houses in the nearby town of Lourdes also begin to break. Gelogists have been called in to investigate.
20 Dec. Three thousand people in rural areas around Gramalote are without food.
22 Dec. Hunger and diseases begin to appear in the shelters of Gramalote refugees in Cucuta. Urgently needed are antibiotics, antihistamines, anti-parasitic, and other drugs.
It appears that the neighbouring villages are also affect by the ground movements. I feel very sorry for all the victims and also that by far not enough is done to relieve their situation…
A slide in California wiped out a stretch of Highway 330 between Running Springs and Highland, near San Bernardino in southern California:
This link has a picture of rocks that fell in Kern River Canyon. The canyon is quite steep, so rockfalls are normal. There are more rockfalls after heavy rains. The boulders are granite.
Just for completeness, here’s a link to a story about a rockfall in Yosemite Park. Kind of “meh” as rockfalls go.