Wednesday, June 19, 2013

Mōiliʻili Karst Water Cave

 
 Honolulu's Secret Underground Caves

Mōiliili Water Cave

Peter T Young 

http://totakeresponsibility.blogspot.com/2012/12/moiliili-karst-moiliili-water-cave.html

The underground cave system is thought to be part of the original channel of Mānoa stream – people call it the Mōʻiliʻili Karst (Karst being a geological formation shaped by the dissolution of a layer or layers of soluble bedrock, such as limestone.)

The wide upslope section of the cave is centered near the intersection of University Avenue and South King Street (down slope from the University Avenue – H-1 interchange.)  The lower edge is located at the intersection of University Avenue and Kapiʻolani Boulevard.

The environment above the karst is highly urbanized, containing busy streets, buildings and businesses. The consequences of such urbanization are evident. Before damages due to urbanization and cave-ins, the Mōʻiliʻili Karst contained a half-mile cave that seemed to be a single connected structure.

There were several ponds that were fed by the karsic springs. One was located west of University Avenue, upslope of Beretania Street (near the UH makai campus.) The Kānewai underground pond was important to Hawaiian culture, because its water was said to have healing properties.

Massive Karst Cave Collapse in 1934
In 1934, a construction project downslope struck a master conduit of the karst. This caused massive water drainage of the upslope area; “for more than four months, an average of 3.8 x 107 L was pumped daily before the hole could be sealed and construction resumed.” The total amount pumped before the leak could be sealed was greater than one billion gallons of water.

The spring-feed ponds vanished within 24 hours.  There have been several instances of collapses since the dewatering. One instance in 1952 involves the Standard Trading store falling through the ground into the karst below it.  Another instance involves the emergence of a large cavern downslope from the King-University intersection.

The leak was repaired, but had changed the karst forever. Several spots in the formation were deliberately filled.  Cave-ins greatly reduced the size of the cave network, and changed access to the underground.

Karst Cave Photo and Video Links:

The Moiliili Karst Formation http://explorebiodiversity.com/Hawaii/hikes/Moiliili/cavemap.html

http://explorebiodiversity.com/Hawaii/hikes/Moiliili/caveorganisms.html

Moili'ili Karst Cave Exploration http://www.alohafrom808.com/2012/06/moiliili-karst-cave-exploration-june-2012/ 

Moili'ili Karst Exploration http://notsogreathikingblog.blogspot.com/2012/06/moiliili-karst-exploration.html

http://www.youtube.com/watch?feature=player_embedded&v=RrGTMYk5cXI

Moiliili Karst http://easyhikerhawaii.blogspot.com/2012/07/moiliili-karst.html

Mōʻiliʻili Karst (Mōʻiliʻili Water Cave)http://totakeresponsibility.blogspot.com/2012/12/moiliili-karst-moiliili-water-cave.html