Fort Bend ISD now reports there have been 89 graves discovered on the future site of the James Reese Career and Technical Center.
Crews continue to sift through the earth daily as they work to discover the cemetery's size.
The property is located on the southwest corner of University Boulevard and Chatham Avenue.
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Charles Kelly is the chairman for the Fort Bend County Historical Commission. He hasn't worked on this particular project. He said land records show the area was used for plantation farming before turning in a prison farm at the turn of the 20th century.
Kelly called the discovery astounding and said it may be the biggest historical cemetery ever discovered in Fort Bend County. He speculated the cemetery dates back to the 1800s.
"When there is no one there to put a little stake in the ground and say this is where the cemetery was, it's going to be lost," said Kelly. "I'm told the people were buried in coffins. They're finding nails and things like that."
Kelly said initial information suggests it was a respectful burial site. He said the best possibility to explain why the cemetery seemed to vanish from recorded history may be a natural disaster. Floodwaters could have washed large amounts of sediments over the location and buried any evidence of the final resting place.
The Fort Bend County Historical Commission documents old cemeteries throughout the region. Kelly said there is at least 160 known locations throughout the county. He said in the years to come, you can expect to see more discoveries as development continues. He said archaeologists ultimately must examine the human remains to find any evidence of who the people buried there may be.