He grew up in Blossom Valley and at the age of ten, Delgado was influenced by lessons on ancient Egypt, Greece, and Rome from his teachers.

[2] By fourteen, Delgado's curiosity led him to a construction site near his home in the Santa Teresa Hills, where the remains of the Ohlone people were discovered.

Delgado, initially volunteering alone, began mapping, photographing, and recovering artifacts from the site,[3] continuing his efforts through high school.

His research notes and materials are archived in the San Jose Public Library, documenting his early explorations of the nearby foothills.

Delgado's early work notably included documenting shipwreck remains and the surrounding environmental conditions exposed by beach erosion.

Delgado remained with the NPS as the first Park Historian for Golden Gate National Recreation Area (GGNRA) serving from 1979 to 1986.

Delgado worked closely with the Park Service's Submerged Cultural Resources Unit after the NPS sent him to the Presidio of San Francisco to attend an Army dive class.

The Initiative later became known as the NPS Maritime Heritage Program In this role,[8] Delgado oversaw the creation of classification standards and guidelines for preservation and documentation.

That meant extensive travel throughout the United States, visiting ships, sailing, steaming, and motoring on them, inspecting them during shipyard haulouts and repairs, climbing masts, crawling through engine rooms, and not just conducting a desk-top survey from afar.

The first inventory of the large historic ships in the United States, led by Delgado, was completed and published in 1990 in conjunction with J. Candace Clifford.

Delgado's work led to the largest group of maritime resources being designated as National Historic Landmarks since the creation of the NHL Program.

This included co-authoring the guidelines for the implementation of the Abandoned Shipwreck Act of 1987[13] following a series of national public meetings,[14] several of which Delgado personally led.

Delgado spent his final field season with NPS in 1990, working again at Bikini, and then leading a team to Mexico to jointly study the remains of the 1846 USS Somers, the setting for the navy's only mutiny and the inspiration for Herman Melville's Billy Budd.

His work included organizing a $3-million reenactment of the historic Northwest Passage and North America-circumnavigating voyages of the museum's centerpiece exhibit, the Royal Canadian Mounted Police motor schooner, St. Roch.

He led the crew that restored Ben Franklin (PX-15), a 130-ton oceanographic research submersible originally built in Switzerland for famed undersea explorer and scientist Jacques Piccard and most famously used on a historic 30-day "drift mission" along the eastern seaboard of the United States in 1969.

He spearheaded a major initiative to relocate the museum from its original, crowded and outdated facilities and to create a National Maritime Center for Canada from 2004 to 2006, but despite gaining federal and provincial support, the effort faltered when the City of Vancouver, despite initial encouragement, ultimately decided not to support moving the museum.

After a one-year sabbatical from the NPS, from 1984 to 1985, to attend East Carolina University, Delgado graduated with a master's degree in Maritime History and Underwater Research.

From 2001 to 2006, he hosted and was the team archaeologist on, the popular Canadian-made National Geographic international documentary series,[20] which drew an audience of over 200 million people in over 172 countries for its six seasons.

He worked with famous novelist, raconteur, and shipwreck hunter Clive Cussler, the series presenter, master divers Mike and Warren Fletcher, and John Davis from Eco-Nova Productions.

During his years with NOAA, he was involved in the Titanic mapping expedition in 2010 as chief scientist, continued his years of study on the Civil War-era, pearl-diving submersible Sub Marine Explorer, participated in fieldwork while reorganizing and focusing the maritime heritage program, and mentored five high school students from Saginaw, Michigan, for Project Shiphunt.

He led the excavation of the Civil War-era blockade-running steamer Mary Celestia in Bermuda, and either led or co-led maritime heritage expeditions in the Alaskan Arctic, in the waters of Greater Farallones National Marine Sanctuary, where the wrecks of SS City of Rio de Janeiro, SS City of Chester, SS Ituna, SS Selja, and USS Conestoga, among others, were discovered, a survey of coastal communities and the maritime cultural landscape north of San Francisco, the sonar survey of the wreck of USS Hatteras, and deep water submersible expeditions off Hawaii that led to the discovery of the Japanese super-submarine I-400 and the former cable-laying ship USS Kailua, ex-SS Dickensen.

In 2017, Delgado retired from public service and became the Senior Vice President of SEARCH, Inc., a major American cultural resources and archaeological firm.

In 2014, he was named an Officer of the Order of Civil Merit, Knight's Cross by His Majesty Juan Carlos I, King of Spain, for services rendered to Spain for the protection of Spanish underwater cultural heritage while President and CEO of the Institute of Nautical Archaeology in the matter of the wreck of the frigate Nuestra Señora de las Mercedes (2014).

[30] In his role as Director of NOAA's Maritime Heritage Program, Delgado mentored a group of five Saginaw, Michigan high school students on a shipwreck research expedition in Lake Huron.