One of the core problems here is the nature of this property. It is privately owned, but the owner is required by agreement with the city to maintain public access to the park around the clock, so the owner does not really exersize full control of the site. I gather that the park was provided by the property owner in exchange for zoning variances on a nearby building.
Since nobody has control of the park, situations like this can fester. I private owner with full authority can have trespassers thrown off immediately. If it were a NYC public park, it would be closed overnight. But this property is neither fish nor foul, so it is difficult to control the situation.
Frankly, the city should just amend the agreement to make the park function like the NYC parks, and have it close down every day from midnight to 5AM. Then it could be cleaned daily and the only mess these idiots could create would be the mess they can create each day.
It may be neither fish nor fowl ... but after several weeks of OWSers crapping in it, I'm sure it's quite foul.
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