The phrase 'reopened since' is correct and usable in written English.
It is usually used to describe a situation in which something that was closed for some reason (such as a business or certain type of location) has been reopened following a period of closure. For example, "The restaurant has been reopened since last month following extensive renovations."
Charity has not reopened since Katrina.
It was the first time the school had reopened since the assault and security was tight.
The Morden Ladbrokes where her husband worked had not reopened since the day of his death.
Private funding markets have reopened since the ECB announced its potentially unlimited bond purchases last August.
The city's only emergency room was at Long Beach Medical Center, which has not reopened since the storm.
The store has reopened since then under new ownership, but with a greatly reduced selection of English-language books.
He has been unable to reopen since August because he has not received any compensation.
It is unclear when the tunnel is going to reopen, since engineers are just beginning to assess the damage to lighting and ventilation systems, for example.
More than 400 businesses have been unable to reopen since Boylston Street, one of the area's main thoroughfares, was deemed a closed crime scene, according to a report in The Boston Globe.
— Jeff Gordinier The New York Post: Bistro vs. bicycles: Jacques Capsouto, 68, staged a sit-in on the curb outside his TriBeCa restaurant, Capsouto Freres, to try to keep city workers from installing bicycle racks outside his establishment, which he has been trying to reopen since Sandy damaged it.
But the threat is serious enough to have kept Baghdad's international airport largely closed to commercial air traffic even though the terminal has been rebuilt and the runways have been repaired, and officials have said it has been ready to reopen since July.
