Meta Engineering

The Bluffs at Waimea, Honolulu, Hawaii

High bluffs are a characteristic feature of the volcanic terrain of the Hawaiian Islands. Most of the island land masses are shield volcanoes. Shield volcanoes are like an ice cream sundae; chocolate syrup (molten lava) pouring down over the ice cream.     

Successive eruptions add layer after layer of lava flow to the existing mountain. Take a car or boat around any island, and the exposed layers of lava rock are visible. Subsequent forces of weather and sun peel off the slopes, leaving high bluffs.

Volcanic rock is one of the fastest weathering rocks on the planet. The action of tropical sun and humidity quickly decomposes the rock to fragments and soil. High iron content of basalt produces the characteristic red dirt color of decomposed lava.

The Bluffs at Waimea consist of a 24-residence subdivision site at the bluff. The property is located on King Kamehameha Highway at the Pacific Ocean. The famous Waimea Beach is situated a couple miles up the road.

The bluff and its remnant soil and rock from decay and decomposition impose challenging engineering conditions. The wet, clay-rich soil is subject to earth movement. Rock fragments from the bluff fall into the property, and springs originating in the Koolau Mountains above the bluff keep runoff moving through the property.

Meta Engineering designed and built a rockfall barrier, stabilized landslides, and drained the springs and runoff.The Rockfall Barrier

A substantial barrier is required because boulders the size of small cars roll down the mountain. We chose an anchored Dura Bloc wall supported on a grade beam 500 feet in length. The grade beam is supported on 40mm grout injection hollow bars drilled deep into the lava rock. The Blocs are anchored with 40mm grout injection hollow bars. Tiebacks are also drilled into the lava rock. 

The wall is six feet high and has stopped many boulders since construction began. A major unstable slope was buttressed with an anchored Dura Bloc wall of similar construction.

Springs and runoff were directed to a network of drainage channels that take all the water to a large catch basin in Tutu Place.