Lawmakers have toured the facilities near downtown and say the center may open as soon as this week.
State Senator Sylvia Garcia met with a Southwest Key lawyer, who said they had all the necessary city permits to open.
Since separated children must be reunited with their parents, the facility will hold unaccompanied minors who illegally cross the border.
Officials say up to 240 children will be housed at the center. State records show Southwest Keys already operates 15 similar facilities across the state of Texas, five in the greater Houston area.
Dr. Juan Sanchez, CEO of Southwest Keys, told ABC13 in June that the facility is not a detention center, but a state-licensed "childcare facility."
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