Ewa Hawaii Karst: Oahu Cave Exploring

Karst Cave Hiking Adventure: Moili'ili Karst Exploration

http://notsogreathikingblog.blogspot.com/2012/06/moiliili-karst-exploration.html

Rather than go into a long dissertation about how this limestone cave system was created here under the shadow of the Ko'olau Volcano, the short version is that a very long time ago the sea level on O'ahu was much higher and the area near the University of Hawaii was once covered by a coral reef.

As the sea levels dropped the reef was exposed to the air and died. Springs and runoff from the mountains above ate into the limestone layer left by the reef creating a network of caves. Most have either collapsed or been filled in over the years.

These systems are also found other places on the leeward coast. This fantastic link that explains everything about this system in far more detail than I could.

http://www.caves.org/pub/journal/PDF/V60/V60N3-Halliday.pdf

Before we go further, despite what the link says the water in the cave system is anything but clean just from visual observation.

Further, access to the system is tenuous at best and there is a danger of both flash flooding and the possibility of a cave in.

Neither scenario is a good one because there is only one way in and one way out of the cave. No directions and no names and, for the record, I was never there either.

I didn't see much in the way of plant or animal life, just a few roots hanging from the ceiling from trees above and some type of small fish. In fact I'd call it more of a guppy than a fish. Others reported seeing some type of shrimp.

Someone spotted a centipede- something no one was excited to hear about but it made for great conversation about how many more there might be down here, what mutant sizes they would reach, and how their appetite for human flesh would have developed.

While it wasn't much of a hike or trail, I'm glad to have had the opportunity to visit this unique and interesting place. Perhaps someday I'll return but I can assure you, it won't be alone and it won't be anytime soon!

http://www.flickr.com/photos/xjcreations/sets/72157630045534695/

Oahu 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

Bio Diversity: The Moiliili Karst Formation

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

The Moiliili Karst Formation is a pie shaped wedge that starts at the University of Hawaii lower campus and extends to approximately Kapiolani Avenue.

This entire section is a limestone base that was formed from an old coral reef. Rainwater runoff from Manoa Valley has caused the limestone to erode, forming the present day karst caves that lie underneath the busy University / King Shopping complexes.

According to Frank Howarth, stresses in a cave environment include, “perpetual darkness and humidity, lack of important environmental cues, complex mazelike living space, stressful or even lethal gas mixtures, patchy food resources, barren rocky substrates, wet and slippery vertical surfaces, and occasional flooding.”

The primary food resources in caves include organic substances that are brought inside by water and gravity. As William Halliday (pers. comm.) observed, the fish inside the (Moiliili) cave were eating something that dripped from a dribble of water. He also noted that “biota is concentrated near the entrance. Large and small roots are present, with mycelia present on some” (Halliday 1994).

Many residents of the Moiliili area are unaware that just a couple meters below their feet, cars, houses, and businesses lies a truly amazing formation. The Moiliili karst formation is not only a “natural laboratory for a largely unstudied groundwater zone,” but also important is the “integration of drainage and economic importance” (Halliday 1998:145).

History of Moiliili Karst

The Karst was an integral part of the economy and world above it. There were several ponds that were fed by karsic springs. One was located west of University Avenue, upslope of Beretania Street. The Kanewai underground pond was important to Hawaiian culture, because its water was said to have healing properties.

Originally the pond was a favorite of Queen Kamamalu (sister of Kamehameha IV and V). The pond served as an enjoyable picnic site for the Queen and her brothers. Hawaiian royalty loved swimming in the ponds, which were also said to have healing powers (Willows Flyer: Appendix A).

The pond became the site of the Willows restaurant, and served as an attraction to customers. It was stocked with koi, which interbred with the existing fish creating a school of colorful fish (Halliday 1998).

The 1934 Dewatering

In 1934, a construction endeavor downslope struck a master conduit of the karst. This caused massive water drainage of the upslope area (Halliday: 1998). According to William Halliday (1998:143), “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 that one billion gallons of water (Halliday 1997).

The lowering of the water table has had several consequences on the surrounding area. The dramatic changes in the karst from before 1934 to present time are a result of the dewatering. There is assumed to have been considerable economic loss as sidewalks split, water and gas mains ruptured, trees sank, and houses rose and settled (Halliday 1998).

The spring feed ponds vanished within 24 hours, taking some fish into the karst, while leaving others stranded. There have been several instances of collapses since the dewatering. One instance involves the Standard Trading store falling through the ground into the karst below it (Watanabe 1996).

Another instance involves the emergence of a large cavern downslope from the King-University intersection. Some fish that disappeared from the Hausten Pond were seen there (Halliday 1998).

Wednesday, June 19, 2013

Karst Cave Hiking Adventure: Moili'ili Karst Exploration

Karst Cave Hiking Adventure: Moili'ili Karst Exploration

Bio Diversity: The Moiliili Karst Formation

Bio Diversity: The Moiliili Karst Formation