No Trespassing

I live in the Lower Mission area and regularly walk my dog up through what is locally referred to as the 'Sand lines'. It's a well used trail and a designated park area and lies to the rear of Coronado Crescent and is bordered on the very top by Westpoint Drive.

The views from the top of the park are quite spectacular. New houses are now appearing on Westpoint Drive that back on to the Park. I don't have a problem with these houses bordering on to Parkland, however, I now notice that one of the trails has been fenced off with trespassing notices posted
preventing the public from walking along the rear of these new houses on
what I believe is Park Land.

I would be interested to hear if any of your readers have commented on this to the parks authorities, or, if they can comment on the legality of these trespassing notices.

M.M.