Trash trap an accident waiting to happen again

Water Ways
Honolulu Star Bulletin (11/20/99)
By Ray Pendleton

A recent break in the Ala Wai Canal trash trap brought back a vivid memory. It happened over 5 1/2 years ago, but I can picture it like it was yesterday.

It was a Thursday evening in March, 1994, and a late winter storm had been inundating O`ahu. In just 24 hours, nearly 13 inches of rain had fallen in Manoa Valley, and its cresting stream was just one of several watershed tributaries cascading into the Ala Wai Canal.

Naturally, when rain falls in such prodigious amounts, even in rural areas, only a small portion can be absorbed by the earth. In a 16 square-mile watershed that is largely covered with buildings, asphalt and concrete, nearly the entire runoff funnels into streams, culverts and storm drains, and eventually flows, via the canal, into the ocean.

Once in the Ala Wai, though, before the runoff gets to the ocean, it passes through the marina near the mouth of the canal, and that is the location of this story.

It is here, in an effort to protect the marina from at least some of the water-borne refuse that flows down the canal, the state attempts to maintain a trap under a section of the Ala Moana Bridge. It consists of two floating booms which collect debris against the wall of the canal. It is cleaned out whenever the harbor master deems it necessary.

On this particular evening, the trap was filled to its capacity with every imaginable sort of junk - from discarded tires and sofas, to tree limbs and packing crates. And the flow of the runoff was pushing against this huge trash-berg with incredible force.

I have never seen the canal's waters look like they did that night. They had the same brown color and rushing, rolling swells one usually associates with the rapids on the Colorado River.

And the runoff from the watershed was aided and abetted by the wind. As darkness approached, it was gusting up to 50 knots, whipping the rain and spray into a frenzy.

Abruptly, the chains connecting the trash-trap booms parted and tons of refuse surged into the main stream of an already debris-choked waterway.

Mixing together in the swirling water, a portion of this floating trash heap began to lodge itself against the boats and docks of the Waikiki Yacht Club 50 yards down stream. What at first began as a tree branch or two, here and there, quickly built into something akin to a series of beaver dams.

As the dams grew, so did the pressure of the wind and water against them. Two of the docks, each containing some thirty boats worth hundreds of thousands of dollars, began bowing downstream.

Suddenly, with a loud crack, mooring cables snapped and the outboard end of one of the docks was quickly swept makai, back into the next row of slips.

Without being asked, dozens of volunteers made their way out onto the bucking, rain- and wind-swept docks to move boats, dislodge the trash-dams and attach new mooring lines to the docks.

Somehow, the boats were saved and there were no injuries or fatalities. But, most of us involved that night thought it could have ended otherwise.

Can the same scenario happen again?

Judging by the fact that the same trash-trap is now over five years older and in obviously worse repair, I think the WYC would be well advised to be prepared for the worst.

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