An overview of projects and missions in the Antilles

Published May 1, 2013
Looking upstream to its source in the central mountains, the Río Puerto Nuevo basin drains 24 square miles of metropolitan San Juan, 75 percent of which is highly developed with a population of 250,000. The plan of improvements includes channels, high velocity channels, debris basins and modifications to bridges, in an effort to protect the population against a 100-year flood.

Looking upstream to its source in the central mountains, the Río Puerto Nuevo basin drains 24 square miles of metropolitan San Juan, 75 percent of which is highly developed with a population of 250,000. The plan of improvements includes channels, high velocity channels, debris basins and modifications to bridges, in an effort to protect the population against a 100-year flood.

This recent aerial shows construction progress on the Río de la Plata project. The river flows by the municipality of Dorado, about 15 miles west of San Juan on the northern coast of Puerto Rico. Looking upstream, the photo shows channel excavation and placement of stone revetment (right), while the river flows through a temporary diversion channel to the left. The revetment will slow the velocity of storm water coming from the mountains upstream and prevent erosion of the banks.

This recent aerial shows construction progress on the Río de la Plata project. The river flows by the municipality of Dorado, about 15 miles west of San Juan on the northern coast of Puerto Rico. Looking upstream, the photo shows channel excavation and placement of stone revetment (right), while the river flows through a temporary diversion channel to the left. The revetment will slow the velocity of storm water coming from the mountains upstream and prevent erosion of the banks.

The Cerrillos Dam was constructed to hold the water that rushes down the Cordillera Central mountain range after rain events, protecting the city of Ponce on the southern coast below.

The Cerrillos Dam was constructed to hold the water that rushes down the Cordillera Central mountain range after rain events, protecting the city of Ponce on the southern coast below.

When it comes to U.S. Army Corps of Engineers’ involvement in Puerto Rico, one might say that its geography is its destiny.

The island’s distinctive topography is the source of much of the Corps’ work in the area. For example, San Juan, the capital on the north side of the island, boasts one of the biggest and best natural harbors in the Caribbean. This harbor has been improved and must be maintained by dredging.

Puerto Rico, at its widest point, is 110 miles long from east to west and only 40 miles wide from north to south. The main mountain range, La Cordillera Central and the smaller cordilleras that run east-west through the center of the island are sparsely populated, but take up half of the available land. Most of the population lives in the narrow coastal band around the cordilleras. In the mountainous region above the city of Ponce in the south, slopes average 45 degrees and Cerro de Punta, the highest point of the island, at 4,393 feet, is only 14 miles from the coast.

Surprisingly, Puerto Rico does not have any natural lakes. It does have 17 man-made reservoirs, commonly known as lakes. The U.S. Department of the Interior’s Bureau of Reclamation and other agencies dammed the main rivers to collect water for irrigation and to generate electricity; the Corps constructed the Cerrillos and the Portugues Dams. There are more than 50 rivers In Puerto Rico, most originating in the Cordillera Central.

Due to the island’s location in the tropics, the trade winds blow almost constantly from the east. When those winds encounter the mountains, the air mass rises, condenses and precipitates. The northeastern section of the island receives more than 200 inches of rain a year, supporting the El Yunque National Forest, the only tropical rainforest in the U.S. National Forest System.

The cordillera collects between 100 to 150 inches of rain per year, while the drier south coast receives only 30 to 40 inches of direct rain per year. That doesn’t mean, however, that the south coast doesn’t receive much water. When it rains in the mountains, large amounts of water rush down the steep slopes to the narrow, flat coastal plain where most people live. The coastal communities that were built around the little rivers and creeks that provided their water supply are subjected to flash flooding.

Col. Alfred B. Devereaux, Jr., Jacksonville district commander from 1981-1984 recognized the potential need for services while visiting a village at the base of the mountains. Water from rains in the central mountain ranges rushed down the street, and within a matter of hours, the water in the area was three feet deep. It provided a crystal clear understanding of the serious and constant threat that flash flooding represented to the coastal communities. The experience helped shape his perception as he envisioned the development of flood damage reduction and water supply projects for the U.S. Commonwealth.
Today, the Antilles Office’s main functions are civil works tasks associated with Corps projects and programs on the islands, principally in the areas of flood damage reduction, navigation, military munitions response and other areas of Corps expertise. It also provides real estate services to all the military branches, and provides support to other federal, state and local entities, as requested and based on interagency agreements. There is also a regulatory mission in Puerto Rico and the U.S. Virgin Islands.

In Puerto Rico, as in the U.S., many Corps projects have had a long history, spanning decades, with multiple planning and construction phases. Similarly, large projects are often broken down into smaller projects, phases and contracts, and moving forward with them is contingent upon congressional authorization and appropriations.

Puerto Rico may be small (slightly less than three times the size of Rhode Island), but it is bustling with activity. Ongoing projects in the North Puerto Rico Resident Office in San Juan include Río De La Plata, Margarita Channel, De Diego Bridge, the Bechara Middle Section, the Center for Disease Control (CDC) and Veteran’s Administration Fire Alarm. Recently completed projects include Fort San Gerónimo, Río Fajardo Improvements and Arecibo Harbor dredging. In the future, another contract is scheduled to be awarded for another section of the Margarita project.

The ongoing projects in the Support for Others Resident Office, also in San Juan, are the Mayaguez Army Reserves, Fort Buchanan Army Reserves, Caguas Army Reserve, Fort Buchanan Department of Transportation and Public Works Building, Navy Operational Support Center (NOSC), Antilles Elementary School, and phase two of the Customs and Border Patrol. Recently completed projects for this office include the Aguadilla Army Reserve Center, and the first phase of a Customs and Border Patrol project.

Yamil Castillo, chief of Antilles construction in San Juan, sees the dedication of the Corps team in the Antilles as critical to moving these projects moving forward. “The people in the Antilles are so committed that they see the Corps as a continuation of their families; not as a job, but as a responsibility and obligation to Puerto Rico,” said Castillo. “I’ve worked several different places, and the people who work for the Corps in Puerto Rico are different. The people in our office get a lot of satisfaction out of their work.

“This week, we had four partnering meetings with prime contractors. Those meetings take a lot out of you, and that was a lot to do in one week, but we had four excellent meetings. Everyone with the Corps comes to meetings with the same type of commitment, attitude and willingness to go the extra mile.”

Alberto Gonzalez is the chief of the flood damage reduction section in the Water Resources Branch of the Programs and Project Management Division in Jacksonville, but he was born in Ponce, on the southern coast of Puerto Rico. Gonzalez was in his first year of college at the University of Puerto Rico at Mayaguez when Hurricane Eloise, the most destructive tropical cyclone of the 1975 Atlantic hurricane season, produced torrential rainfall throughout Puerto Rico, causing extensive flooding that led to severe damage and more than 40 deaths. Thousands of people in these areas became homeless as flood waters submerged numerous communities.
Right after college, Gonzalez was offered a job with the Corps -- in Jacksonville. At the time, he had no way of knowing that during his 32 years with the Corps, he would work on most of the flood damage reduction projects in Puerto Rico and that he’d be the project manager for the last piece of the Portugues and Bucaná Rivers flood damage reduction project that included the Cerrillos Dam, northeast of Ponce, and the Portugues Dam, the main ongoing project for the South Puerto Rico Resident Office in Ponce.

“We have worked on projects such as the Río Puerto Nuevo, Río de La Plata, Río Grande de Arecibo and Río Ojo de Agua, which are flood damage reduction projects and of significant importance to the Commonwealth of Puerto Rico,” said Gonzalez. “As a public servant, it was a source of pride for me to be able to provide flood damage reduction to the citizens of the U.S., the U.S. Virgin Islands and Puerto Rico. I didn’t want others to go through the pain I witnessed when I was a college student.” 

Gonzalez’s focus is now on the completion of the Portugues Dam, to protect the people in his hometown of Ponce. The Portugues Dam is the first thick arch roller compacted concrete construction (RCC) dam in U.S. territory. Rolled concrete has the same basic ingredients as conventional concrete, including cement, water and aggregates, such as gravel or crushed stone. However, it's a drier mix than conventional concrete, and is stiff enough to be compacted by vibratory rollers. Gonzalez and his team proudly presented the use of RCC construction technology on the Portugues Dam at a recent international conference.

 “Construction on the dam in Ponce is expected to be completed in late 2013 and later transferred to the Department of Natural and Environmental Resources, which is the local sponsor for about 80 percent of our projects,” said Gonzalez.

Another longtime project that demonstrates the scope and complexity of flood damage reduction projects in Puerto Rico is the Río Puerto Nuevo project, originally authorized by Congress in the Water Resources Development Act of 1986. Rapid upstream runoff, inadequate channel capacity, constriction at bridges and elimination of the natural floodplain by urbanization resulted in severe flooding for 7,500 residents and 700 commercial and public structures valued at over $3 billion, including the most important transportation facilities and strategic utility complexes. The plan of improvement protects against the 100-year flood and includes lined channels and high-velocity channels, debris basins and construction, replacement or modification of many bridges.

“Puerto Rico got good news in the president’s budget in April. The Río Puerto Nuevo project received funding,” said Gonzalez. “Now that we have the federal piece in place, we need to work with the local sponsor on their part of the commitment. Like any civil works project, there is a required cost share agreement. The local sponsor can help with things such as the purchase of property necessary to move the project forward.”

Caño Martin Peña (CMP), authorized in the Water Resources Development Act of 2007, is the largest ecosystem restoration project on the island and also expected to provide flood protection benefits to the densely populated wards of the city. The Caño Martin Peña is a natural tidal channel that runs through metropolitan San Juan. Historically, it had an average width of 200 feet and a depth of between 6 to 8 feet, and provided tidal exchange between San Juan Bay and the San José Lagoon.

Since the 1920s, housing structures were constructed in the wetlands. These developments lacked basic utilities such as storm and sanitary sewers or adequate road infrastructure for a proper solid waste system. The people living in thousands of structures discarded refuse into CMP for decades. Siltation, accumulation of household and construction debris, industrial waste, encroachment of housing and other structures, and sedimentation from urban runoff have almost completely blocked the CMP’s ability to convey flows. Dredging the eastern segment of the 2.2 mile-long canal, to restore the CMP and adjacent areas and to increase tidal flushing of the San José Lagoon and reduce flooding within the CMP’s eight adjacent communities, was completed in 1988. A feasibility report prepared by the local sponsor for additional dredging and restoration work is under review by the Office of the Assistant Secretary of the Army for Civil Works, with approval anticipated by spring 2014.

In addition to the environmental issues of flash-flooding, erosion, periodic droughts and water shortages, Puerto Ricans also deal with the Atlantic hurricane season from June through November. Responding to these events is another mission embraced by the Antilles Offices.

Long-time Corps employee Elsa Jimenez served as a public affairs specialist for 32 years. Jimenez worked on many of the projects in Puerto Rico, including emergency and disaster response missions. Now enjoying retirement, she reflected back upon what she calls her most meaningful work: “I remember dearly the opportunities we had to work, helping so many before, during and especially after several big hurricanes in Puerto Rico, the U.S. Virgin Islands and even in Miami.”