admin's picture

U.S. plans to dredge coral reefs at Apra Harbor

By Brett Kelman HAGATNA, Guam (Pacific Daily News, Jan. 4, 2010) – In Guam, aircraft carriers will inject new income into the local economy thanks to the coming military buildup, but the wildlife in local waters must pay a heavy price for growth.

The construction of a new aircraft carrier wharf in Inner Apra Harbor will allow the biggest ships in the Navy to quadruple the amount of time they've spent on Guam in recent years.

During each visit, thousands of sailors will come ashore and spend money that would otherwise go elsewhere, according to the Draft Environmental Impact Statement (DEIS), a massive document that explains what will happen when the buildup arrives.

But to build a new carrier wharf, the military must widen a shipping channel and dredge seabed that contains flourishing coral and valuable aquatic life, the document states.

A popular scuba diving site may be ruined by unsettled silt.

It is common for massive progress to force controversial trade-offs like this one, which could split public opinion down the middle, said Roseann Jones, a University of Guam professor of economics.

Some people will be happy to trade coral for commerce and some won't, Jones said. Regardless, Guam residents should understand the deal being made before their eyes.

"The public needs to have a very clear understanding of what they are trading off and if what they are getting is enough in return. They cannot be shy ... What often happens in a blizzard of economic growth is people are unsure what to ask for," Jones said.

Once the new wharf is functioning by 2015, aircraft carriers will spend about 63 days a year ported in Guam, according to the Draft Environmental Impact Statement.

About 5,600 personnel work on a single carrier, the document states.

Many of those personnel will leave their ship and explore the island. Their spending is expected to inject about US$13 million into the local economy every year once the wharf is built.

Stimulus will be even higher from 2011 to 2014, when the wharf is under construction. About US$21 million to US$28 million of additional money will be spent on Guam during each of those four years, the draft EIS states.

Construction of the new wharf will also create nearly 1,100 civilian jobs by 2012, the EIS report states, but most of those jobs will disappear in two years when construction ends.

Money that is brought to the island from the wharf and carriers will cycle through the economy again and again, boosting Guam's Gross Island Product (GIP), Jones said.

"As the Gross Island Product ... improves, generally the economy is better off. You should be able to see it create revenues for government and better investments by governments in schools and hospitals and roads. When economies are doing better, things begin to look better."

And before that money trickles to local government it will pass through the hands of local businesses. Some land-starved sailors will spend on everything and anything.

That includes tattoos, said Harv Angel.

More carriers and sailors can only benefit Angel's business, Low Tide Tattoo. Angel said he is looking forward to the days when the wharf is complete.

"Cha-ching!" Angel said Thursday, laughing. "This will help everybody -- from me to Kmart. Those dollars go through the entire community."

Although the new wharf may promise a step forward for Guam's economy, it will leave a big footprint on the bottom of Apra Harbor.

The military must clear a path through the shallows leading to the wharf so the gigantic carriers have enough space and depth to maneuver through the harbor, according to the draft EIS report.

The Department of Defense (DOD) plans to widen an existing shipping channel so a carrier can fit through. To create a turning basin near the wharf, about 2.3 million square feet of sea floor will be dredged.

That's enough space for 40 football fields or 2,000 average-sized Guam homes.

About 35 percent of that area is covered in coral reef that will be permanently destroyed, the draft EIS states.

Brent Tibbatts, fisheries biologist at the Guam Department of Agriculture, said the military is underestimating the amount of coral in the dredging area.

Because the Department of Defense used satellite imagery to measure the coral in the area, it is difficult to calculate how high it is piled.

For example: A meter of coral or three meters of coral would look about the same from space, Tibbatts said. But smaller, rarer life could be hidden where the satellites can't see.

"Supposedly, there have been things found in Apra Harbor that have been found growing nowhere else in Guam," Tibbatts said.

One of those things are 6-foot brilliant blue elephant ear sponges that stand out among the common mounds of yellow, brown and green coral.

It is rare for a busy port to be teeming with marine life like Apra Harbor, Tibbatts said. Most of the ports of the Pacific have barren sea bottoms, not lively ecosystems.

Many of the organisms in Apra Harbor will be buried during the dredging, according to the Draft EIS. Some will survive and seek new homes elsewhere in weeks or months, the document states. Other colonies of fish that are attached to their territory -- like damselfish, clownfish and butterfly fish -- will die.

The draft EIS also states that ship traffic and dredging will create "short-term" disruption in the birthing area for scalloped hammerhead sharks. The sharks give birth directly in the carriers' path into the wharf, the draft EIS states.

Although the adult hammerheads spread to waters around the island, Apra Harbor is the only place they consistently return to give birth.

If the dredging lasts more than a year, it could easily disturb two breeding cycles for the sharks, Tibbatts said. Since they only give birth to a few babies a year, local populations will be affected.

"It would not be easy for them to replenish the population if something impacts their ability to pup," he said.

The damage done to the marine ecosystem could be worse, according to the draft EIS.

Currently, the projected route of carriers would pass between several reefs out to halfway across Outer Apra Harbor. Then it would turn sharply to the left and sail straight out to sea.

From a navigational standpoint, it would be preferable to sail straight out of the harbor or make a more gradual turn, but these options were dismissed because they would damage too much coral, the document states.

There is no question that some coral will be destroyed directly during the wharf's construction, but the military and local experts disagree about the large-scale impact of dredging in Apra Harbor.

Although the project will uproot about 600,000 cubic yards of sea floor, silt will only spread about 40 feet outside the dredging zone, according to computer models cited in the draft EIS.

A 200-meter "indirect impact" buffer encircles the dredging zone, but the military has overestimated the spread of silt as a precaution, the document states. This buffer is "very conservative," the document states.

Tibbatts doesn't think so.

"I've looked at the computer modeling they've done and my concern is that it is just a model. It's not reality," he said on Wednesday. "We've had experience with other dredging projects in the harbor where modeling said silt wouldn't go beyond a certain point and in reality it went far beyond."

When the military built Kilo Wharf in the harbor in the 1980s, silt spread farther than expected, he said. When the military dredged the harbor to expand Kilo Wharf last year, silt again spread farther than expected.

Those projects were nowhere near as large as the dredging needed for the new wharf. If estimates are wrong again, nearby reefs -- including popular dive site Western Shoals -- could be dusted with disturbed silt.

The silt would starve the reef by blocking sunlight and stunting the food chain before it begins, Tibbatts said. Once silt settles, coral would become unhealthy because it must waste energy to shed the coat of silt.

If the coral at Western Shoals is weakened, the fish that depend on the reef will leave or die. When those fish are gone, their predators will look elsewhere for food.

And when life empties off the reef, the scuba divers won't go to Western Shoals. Currently, many go there every day.

The west face of the horseshoe-shaped reef slopes gradually from the surface to the depths and is home to a startling amount of fish, said Pete Peterson, a scuba expert who hosts Diver Below, a local television show.

"There are an amazing amount of critters in that one area and it's a very easy dive so a lot of beginning divers go there," Peterson said. "Every day the tour companies go there."

Like Tibbatts, Peterson is confident dredging will spread silt farther than the military estimates.

During the last 15 years, increased ship traffic and dredging in the harbor has reduced visibility for scuba divers by 50 percent and destroyed a quarter of the coral, Peterson said.

Because the harbor is sheltered by land, tides don't sweep very much loose sediment out to sea. Most of the silt settles on the harbor bottom and stays forever, waiting to be stirred up by the next passing ship, he said.

Rate this article: 
No votes yet

Add new comment