The last time I heard from Greg Brooks, the Portland man who sold his swimming-pool business more than 20 years ago to search for treasure-laden shipwrecks in the Caribbean, he was hopeful that he had found one of the richest vessels ever to be lost at sea.

The Nuestra Senora de Deliverance, a 166-foot armed merchant vessel sailing under a Spanish flag, is believed to have gone down off the Florida Keys in a hurricane in 1755, a day after departing Havana, Cuba, for Cadiz, Spain. Brooks got a federal claim on the vessel about a year ago, which allowed his Portland-based Sub Sea Research LLC to “arrest” the shipwreck and protect it from modern-day pirates. If Brooks’ extensive research were to prove correct, he told me at the time, the 18th century wreck could contain a bounty of gold, silver and jewels worth as much as $3 billion.

But nothing is ever certain in the shipwreck business, and the legal complications are extensive, so Brooks has spent the last year or so doing an extensive survey of the site to determine whether this really is the Deliverance or perhaps another vessel of similar historical importance.

In the meantime, however, Brooks also has been busy pursuing another big dream he’s had for the last decade or so, this one to help retrieve Haiti’s abundant maritime history that now lies buried along its coast and to share its treasures with the people of that impoverished nation.

According to a recent press release, Sub Sea contracted with the Haitian government last week to “rescue international maritime heritage sites” located in three large areas along that country’s north, west and southern coastlines.

“The waters around Haiti have been ignored and overlooked for too long,” wrote Brooks, who is now in Haiti’s capital city of Port-au-Prince. “There is too much history lying on or under the seabed, rotting away. We have the technology and the resources to be productive partners in this with the Haitian people.”

He explained that hundreds if not thousands of ships were once lured to the multitude of naturally protected deep bays and harbors surrounding Haiti, which lies in the middle of what was one of the most popular Dutch West Indies trade routes centuries ago.

“It was also one of the strongholds of buccaneers, privateers and freebooters throughout this period,” he wrote, “and therefore illustrates the incredible wealth of seafaring history lying in repose off Haiti’s shores.”

The company’s four-year partnership agreement with the Haitian government allows Brooks and his archaeologists to begin surveying what he calls the “shipwreck soup” along the coast and eventually to bring up whatever items may be hidden among the remains of wooden ship hulls that disintegrated long ago.

“There’s not much left to the wrecks anymore,” said John Hardy, a retired space-industry engineer who has been Brooks’ partner for more than six years. “What we see now are the lead shells that once covered the hulls and the ballast piles. There could be gold and silver coins, emeralds and many other valuable items in the piles.”

The Sub Sea team, Hardy said, is preparing to bring up more than 75 ornate bronze cannons that have already been located among the Haitian wrecks. Each one is worth anywhere from $40,000 to $100,000, he said. In exchange for its salvage rights, the company will share 10 percent of its profits with the orphanages of Haiti and eventually build a maritime museum there that would house items of archaeological significance.

“We know that as this project develops it can add a lot to the economy there over the long term,” Hardy said, “as well as help restore a part of their maritime history that’s been neglected for so long. We’re very committed to doing something positive and creating economic opportunities for the people, who are among the poorest in the world.”

The company also recently got Gov. John Baldacci’s endorsement for an ambitious plan to build a Maine shipwreck museum on the Portland waterfront. The proposed “musarium” would house maritime artifacts recovered from the company’s many exploration sites around the world, as well as a marine habitat, an exhibit of seafaring craftsmanship and a gallery of maritime art.

“It’s taken years of hard work to get to this point,” Hardy said, “but with everything that’s happening in Haiti right now, we’re looking forward to some very exciting times.”