Baldwin Hills store

from Wikipedia, the free encyclopedia
Baldwin Hills store in 1963 after the dam collapsed

Map: USA
marker
Baldwin Hills store​
Magnify-clip.png
United States

The Baldwin Hills Reservoir was a reservoir in Baldwin Hills near Los Angeles in the US state of California . It broke in December 1963 and created a tidal wave that is said to have been 15 meters high and caused $ 50 million in damage. There were five to eight fatalities.

The rectangular pool was built in 1951. It was about 260 by 305 m and had a circular dam about 40 m high. According to ICOLD it was even 80 m high, according to Flemming (see below) 70 m. The surface was sealed inside with asphalt concrete . Underneath was a drainage layer . The basin volume was 1.1 million m³, of which 200 million gallons (= 756,000 m³) or even 930,000 m³ leaked.

There were several geological faults underground, but they were known. The ground subsided due to earthquakes, subsidence of the groundwater level, and oil production nearby. Around 800 m from the basin there was a settlement basin 3 m deep, which had been created over the course of 50 years. Directly at the pool, however, the subsidence was only 3 cm deep.

On December 14, 1963, a Saturday, the dam broke over the course of several hours. First of all, at 11:15 a.m. in the morning , the dam master noticed muddy seepage water on the drains , then heavily bubbling sole drainage. From 12:20 p.m. they tried to empty the storage tank. However, cracks formed too quickly in various places, which finally led to a breach and leakage around 3:00 p.m. Flemming gives the width of the crack as 23 m and its height as 27 m. The tidal wave was over after three to four hours; According to Flemming, the runoff only took 77 minutes. The maximum flow rate was 120 m³ / s.

Six hours before the break, the people below are said to have been warned so that they could leave the endangered area. (However, this time does not match the above times; you could have been warned at around 12:00 noon at the earliest.) Nevertheless, there were at least five fatalities. 41 houses were destroyed and 984 damaged. According to Flemming, the property damage amounted to 50 million DM (instead of dollars).

It was later found that movements on the faults had broken the drains. The water ran down and seeped underground, creating erosion, an effect called piping . Eventually the asphalt concrete seal was also torn by movements at the faults.

The dam was not rebuilt. The Kenneth Hahn State Recreation Area has been made out of the site .

See also

Literature / sources

  • Peter Rißler: dam practice. Oldenbourg, Munich / Vienna 1998, ISBN 3-486-26428-1 .
  • HW Flemming: Energy for the world, large dams in five continents. Ehrenwirth, Munich 1967.

Web links