The U.S. Army Corps of Engineers has signed a $1-billion agreement with the Puerto Rico Electric Power Authority to make permanent repairs and improvements to the island nation’s beleaguered Guajataca Dam.

Puerto Rico Gov. Pedro R. Pierluisi announced the agreement, saying the Corps will support the dam's reconstruction, including design, engineering, procurement, contract administration, construction supervision and project management. The agency said the U.S. Federal Emergency Management Agency (FEMA) will provide funding for the project, to be completed in 2028.

The Lake Guajataca reservoir currently provides drinking water to more than 300,000 in the cities of San Sebastián, Quebradillas, Isabela, Moca, Aguada and Aguadilla as well as providing water for agricultural irrigation. Construction efforts will also restore and modernize the dam's hydroelectric capability, which was shut down following damage from Hurricane Maria. 

Built in 1928, the 984-ft-long, 120-ft-tall hydroelectric earthen dam, located in the island’s northwestern region, experienced a critical failure on Sept. 20, 2017, following Hurricane Maria. The Category 5 storm, with winds reaching 175 m.p.h., killed more than 3,000 people and caused more than $91 billion in damages. The dam suffered severe damage to its spillway, pipes and water intake, endangering 70,000 residents.

Immediately after the storm, FEMA, the Corps and Puerto Rico utility PREPA led emergency repairs to the structure. After stabilizing the dam, efforts focused on mitigating future risks by repairing existing openings and gates and reconnecting the water pipe between the reservoir and the canal.

According to the Corps, risk reduction measures completed in 2018 and 2019 have provided about a 1,000-year level of flood protection and further reduced risk of the dam failing. The agreement moves the Guajataca Dam project to its final stage where permanent repairs will be completed. 

The project includes an early warning system that will notify emergency management agencies in advance if an event may require an eviction or any other action that is necessary to save life and property, officials said.

"By signing this agreement, we guarantee the permanent repair and improvement of the Guajataca Dam," said utility executive director Josué Colón. "The rebuilt facility will comply with current safety codes and provide peace of mind to the surrounding municipalities and benefit those who rely on its water storage.” 

Gov. Pierluisi called the project "another example of our administration and the federal government working together for the benefit of our citizens."

Brig. Gen. Daniel Hibner, Corps South Atlantic Division commander, acknowledged challenges faced by Puerto Rico's electrical grid, which were exacerbated by Maria and more recent hurricanes and tropical storms. “The Corps of Engineers is leveraging its technical expertise to increase power generation and establish infrastructure for rapid response to power generation and repair issues,” he said.

The agency also is working on more redevelopment efforts there, which include flood control initiatives for Río Puerto Nuevo, a $1.5 billion project; and others for Rio de la Plata ($485.2 million), Río Grande de Arecibo ($174.1 million), and Río Guanajibo ($107.1 million). Other projects include construction  of the Army Reserve National Guard Joint Training Center ($291 million) and the Ecosystem Restoration Project, Caño Martin Peña.