West Lothian Council planners rubber-stamped the move with a lengthy set of conditions on the work that must be done, traffic calming and elements of the proposed development, including retail.
The green light has condemned some of the listed buildings on the site to be razed but will also preserve the most important ,including the church and the recreation hall which will be incorporated into a new primary school for the area.
Allanwater Developments and its partner firm Ambassador Homes propose to build 998 units on the site - only around 90 of which would be incorporated into existing listed buildings .
Describing details of the proposal, Bob Evans for the developers said there are around 36,000 trees on the site but only one third are original and the remainder are later “plantation” style growth. For all trees removed new one would be replanted.
David Gaffney of the Ambassador Group described the application as a milestone and hailed the potential economic input into the county from its development.
The developers contend that development is financially unviable unless a lot of homes are built.
During the meeting, several councillors raised family and emotional connections to the site.
Councillor Harry Cartmill, one of Bathgate’s Labour councillors, whose mother worked as a wartime nurse in the hospital. said he had very deep concerns about the proposals.
He added: “Parking in the town is a constant issue for myself and the other councillors in Bathgate. We are going to be inundated if we are seen to approve this knowing its knock on effects. I don’t think we are doing our job.”
But councillor Bruce Fairbairn said: “I think this is a great opportunity for this council to bring West Lothian further into the 21st century. Nothing this size comes without challenges so we should rise to this challenge.”
In June, Police Scotland stepped-up patrols, using tracker dogs, amid a security crackdown at the former psychiatric hospital which is a draw for "ghost hunters" from far and wide
It is also lauded as "one of the most atmospheric places in Scotland" by tourist website Undiscovered Scotland.