Updated at 5pm with FAA reaction
Plans for a 133-home residence and other facilities in Wied Għomor, were ditched by the Planning Authority on Thursday.
The developers had appealed a decision after the project had been unanimously rejected by the Planning Authority board in May 2016. The final decision on the valley which divides Swieqi from San Ġwann was taken by the Planning Review Tribunal
Swieqi mayor Noel Muscat described the decision as a victory for common sense and the environment.
The decision should send a clear message not just for the protection of Wied Għomor but also other valleys and areas of protection, he said.
Read: Last ditch effort to save Wied Għomor
Wied Għomor, a scheduled area of ecological and scientific importance, has been subjected to an unprecedented barrage of development applications in recent years, stretching local councils to their limits in an attempt to preserve its rural character.
Environment Minister José Herrera had said he had personally proposed the threatened valley for protection under the Public Domain Act, which would have offered a further safeguard against commercialisation and overdevelopment.
Decision welcomed
In a statement, Environment Minister Josè Herrera noted with "satisfaction" the PA tribunal's decision.
The minister said he will carry on with the process of giving the valley the necessary protection.
Flimkien għal Ambjent Aħjar said the decision meant the valley has been protected against irreversible harm for the foreseeable future.
"FAA urges the government to protect Wied Għomor and other valleys threatened by urban sprawl by giving them the elevated protection they deserve," it added.