Some 19th-century buildings took on 8 or more feet of water, said Galveston Historical Foundation executive director Dwayne Jones. Among them were the 1861 U.S. Custom House that serves as the foundation's headquarters.
Galveston's city historic preservation officer and building officials were examining historic structures Monday to further assess damage, Jones said. He repeated the warning from local authorities that those who own island property should not immediately return.
"This is not a time to be there. This is not a time to go to the island," Jones said. His staff is operating temporarily from the Preservation Texas office in Austin and doesn't expect to be back on the island until after this week, he said.
Of the approximately 7,000 documented historic island properties, Jones estimated as many as 1,500 were seriously damaged by the weekend storm. Some buildings date to the 1830s, but a large number were built in the 1870s to 1890s.
"We have some of the largest collections of historic buildings in Texas and in the country," Jones said. "We really were very much the gateway to Texas as the many immigrants and people who came to settle the state and country came through Galveston. ... We have a very rich history."
He said the 17-foot Galveston seawall -- erected after the infamous 1900 hurricane that killed thousands and remains the subject of island lore -- helped protect historic island sites.
Based on reports from foundation staff members and others who remained on the island, Jones gave a rundown of how notable Galveston structures appeared to have fared.
The 1859 Italianate mansion Ashton Villa lost windows on its second floor and had up to 18 inches of flooding, which likely caused extensive first-floor furniture damage.
The popular Bishop's Palace -- the 1889 Gresham House that is the most visited historic building in Galveston -- appears to have sustained little damage. The home did experience flooding on its bottom floor, which is slightly below ground level and is used for a ticket counter and offices.
The famous 1877 ship Elissa lost several sails but seemed to ride out the hurricane well, Jones said, adding that the Elissa sails every spring and should be able to make her annual March voyage. The vessel is attached to the shore through large steel pipes driven into the harbor bottom.
"We're very pleased that the Elissa has survived this storm, as she has many other hurricanes before," Jones said. "She's very seaworthy and very strong."
Galveston officials say they have been preparing for this type of direct hit by a hurricane.
Ike was a Category 2 storm, and had it been a Category 3 with stronger winds it would have been devastating for the old buildings, Jones said.
"It certainly could have been worse," he said. "But it's certainly not good."
Preservation officials have an extensive digital photo catalog of historic buildings to work from for repairing and restoring the structures, Jones said.
Larry Oaks, executive director of the Texas Historical Commission, encouraged those interested in information on or donating to historic preservation efforts in the hurricane-damaged region to visit the commission's Web site.
The Galveston Historical Foundation is working with other historic preservation groups and lining up recovery team volunteers for when a return to the island is possible, Jones said.
"We're all geared up and ready to go back on the island and get to work," he said.