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In San Juan, Puerto Rico, Cao Martn Pea On Verge of Restoration

BY KATIE WORTH

Once upon a time, the Caño Martín Peña was a 200-foot wide, 10-foot deep, navigable waterway through the heart of San Juan, Puerto Rico.

Today, there are parts of the Martin Peña that you can jump across.

The Martin Peña is an estuarial channel that connects San Juan Bay – home to Puerto Rico’s most important port, and San Jose Lagoon – a delicate ecosystem right in the middle of urban San Juan. For a century, the channel has been a dumping ground for trash and sewage, and it has shrunk to little more than a trickle.

But community leaders in Puerto Rico hope that will finally change. For more than a decade, community and government groups have been garnering support for an environmental dredging project along the channel, to restore it to its original dimensions. The going has been slow – it would involve relocating thousands of people who have built their homes on the trash in the waterway, and the project is only partially funded. But environmental and public health officials agree that environmental dredging must occur for the estuary to return to health.

The Martin Peña’s woes began early in the 20th century, when San Juan’s population boomed and the poor and working people were looking for places to live. They were pointed to the Martin Peña, which cut a wide swath across the middle of the expanding city. There, trash was dumped to reclaim land in the waterway, on top of which homes were built. For decades, many of these homes lacked even sewage systems, and garbage continued to build up in the channel – leaving less and less room for water to flow.

This pattern all added up to an environmental disaster, which is still causing problems today. The mangrove forests that once flourished in the channel – and the creatures who depended on them – disappeared. The rest of the estuary’s ecosystem was also affected: the Martin Peña served to circulate water through the bay and nearby lagoons, but once it became clogged, their water quality suffered.

The contamination has affected public health. According to the Proyecto Enlace del Caño – the public corporation now coordinating the cleanup and development of the area – water samples from the channel show some two million fecal coliform colonies per 100 ml – about 10,000 times higher than the accepted standard of 200 colonies per 100 ml.

And a recent study conducted by the Ponce School of Medicine discovered that people get sick much more in the communities that live over the channel. Thirty-one percent of people living in those communities suffer gastrointestinal problems, compared to 22 percent of the general population in Puerto Rico. Children under five living in the communities have a 44.5 percent chance of developing bronchial asthma – compared to a more moderate 21 percent in the rest of the U.S. territory’s population.
These recent public health revelations make Jose Soto, a life scientist with the U.S. Environmental Protection Agency, hopeful that the project will get the attention it needs more quickly.

“It might be something that pushes everything toward additional attention, and it might result in additional funding,” he said.

This isn’t the first dredging project on the channel. In the 1980s, the western half of the Caño Martín Peña was dredged. Like the eastern half, it had been reduced to a trickle because of the homes built over trash. However, at that time, the environmental and health concerns were not a primary motivation. Rather, the waterway was dredged to make way for a federally funded public transit project called the Agua-Guagua.

The concept was to make the western half of the Caño Martín Peña navigable by boat, to ferry people between the city’s financial district and the Old San Juan neighborhood. To do so, the government forced thousands of people to move off of their property and into public housing projects, at a government cost of $125 million. That relocation is now thought to have been handled poorly, and to have further impoverished those who were removed.

The $20 million construction project that followed removed 1.3 million cubic yards of dredged material, depositing it in an off-shore disposal location. As a result, a 200-foot-wide and 10-foot-deep channel was created. The public has not embraced the transportation project, but the environmental and recreational benefits along the western Caño Martín Peña have been positive.

Enlace has taken considerable steps so the dredging of the eastern half of the Caño Martín Peña will avoid most of the problems that arose when the western half was dredged, said Lyvia Rodriguez, the organization’s executive director. Some 700 public meetings during 10 years have been held to air public concerns and garner public support for the project.

The project is undergoing a feasibility report and a declaration of environmental impact, the draft of which is due out in early October. The U.S. Army Corps of Engineers is among the authorities that must approve the documents before the project goes forward, and representatives of the U.S. EPA sit on the review’s technical committee.

If the Corps gives its stamp of approval, federal dollars will begin flowing to the project. In 2007, the U.S. Congress appropriated about $150 million for the project, on the condition that the Army Corps approved it.
But that money won’t be enough to fully fund the project, said Rodriguez. The entire project, including the relocation of thousands of residents, will cost about $600 million, she said.

Soto said Martín Peña is now one of 10 locations being considered for inclusion in the National Urban Waters Federal Partnership, which would draw much more federal attention to the project, and possibly more funding.
But even if they get all the funding right away, the soonest dredging could occur is three to four years from now, because of the time the relocation of residents will require, Rodriguez said.

An environmental dredging company would be contracted to remove the material using bucket dredges and barges, she said. They estimate that to clear the waterway to a 100-foot width and a 10-foot depth will require the removal of 825,200 cubic yards of material.

According to Soto, the dredging would have to be conducted carefully and precisely. Preliminary environmental studies show that there are some contaminants that would cause more problems to be removed and possibly re-suspended, than to simply leave there, so in some areas, the depth dredged would be less than 10 feet, he said.

About five percent of the dredged material is believed to be voluminous waste material, like car engines, which would be removed to a landfill or a recycler. The remaining 95 percent, however, would be removed to a disposal site —perhaps even within the estuary. While most of the estuary is only a few feet deep, there are several “artificial depressions” in the lagoons and channels, where, in the 1950s and 1960s, sand was removed, or a site was prepared for a marina that never arrived. In those locations, the water depth drops to 20 or 30 feet.

These pits create anaerobic conditions in the lagoon, and therefore are their own environmental problem — which has led to the consideration that they could make ideal deposit sites for dredged material, said Soto.

Rodriguez explained that they would first be lined like a landfill, and the dredged material would be carefully deposited in them. They would then be capped and covered with a few feet of sand, she said. Mangrove forests would be planted on top of the filled sites, she said.

The environmental impact report is examining whether this disposal method would be possible, without further contaminating the estuary, and whether it could, in fact, help restore the natural state and habitat of the waterways, and solve the problem of the anaerobic pits.
Though the material is indeed contaminated, the environmental impact report indicates that this disposal method would not further contaminate the estuary, and indeed, would help restore the natural state and habitat of the waterways, and solve the problem of the anaerobic pits.
“We’d take care of two problems at the same time,” said EPA’s Soto.

The project still has a long way to go before dredges will be seen afloat on the Caño Martín Peña, but it is imperative that they eventually are, Rodriguez said.
“Certainly this is a project that has big benefits for Puerto Rico – from the point of view of the environment, from the point of view of public health, and from the point of view of urban and economic development,” Rodriguez said. “The Caño is in the heart of the city, and its rehabilitation will allow for the reconnection of a series of waterways. At the same time it would provoke the possibility of real urban development in the zone.”

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