Sediment Breeds Sentiment

Molokai residents have renewed interest in preservation of natural resource.
By Sean Aronson

is feral ungulates,” says Brown. In plain English, that means the goats, pigs and deer that populate much of Molokai’s open land. Their actions create erosion, which in turn speeds up the process of sediment reaching the reef.

While it is true that increased flow in the harbor would result from the culverts, according to Brown, that sediment would need somewhere to go.

“Just because the sediment is no longer on the reef,” says Brown, “there’s still no guarantee it will leave the area.”

Again, Brown emphasized the main problem as soil from the land blowing onto the reef.

Brown says it is instructive to look at Lahaina in comparison with Kaunakakai. The reefs in both areas were severely impacted by Hurricane Iniki in 1992, but Lahaina’s reef has recovered much quicker.

That’s because Lahaina stopped major sugarcane growing in 1998, which allowed for increased erosion control, says Brown. On Molokai, erosion is getting worse, not better, says Brown — meaning more sediment on the reef.

For Jerry Johnson, even if culverts in the wharf are only a short term solution, at least it’s a start. And he says the Army Corps report is reason enough to make something happen.

In 2001 analysis, the Army Corps created a model of the Kaunakakai Harbor to test whether culverts would improve the flow of water in the area, thus creating less stress on the reef. The results were mixed. Under certain conditions, wave heights and tides, there was a perceptible reduction in the amount of particulate matter in the harbor area. But it also concluded that the sediment was just as likely to be held up in the harbor if conditions were not just right.

Still, Johnson would like to see money from the Federal government go to the wharf improvements. He says there is money set aside for habitat improvements and the culvert project would no doubt qualify.

For now, residents will continue to brainstorm and push for action on the reef — with or without government support.

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