Boston Globe: Popular Lawn on D may be too costly to keep going
The Lawn on D has a budget of $2.2 million and expects to generate a bit over $300k in revenue, so it might have to close down.
For comparison, the Greenway has a budget of $4.2 million ($2 million state subsidy, $578k revenue, remainder donations and endowment returns). NY's Bryant Park--the shining example of a privately funded park--has a budget of $12 million ("funded by sources such as corporate sponsorships, concession fees, and payments from nearby property owners"). Massport (a governmental agency similar to the BCCA)
expects that "more than $5 million will be spent maintaining and growing the park system Massport operates in East Boston and South Boston" in 2016. Post Office Square is paid for by the garage below, but it had a $2.9 million annual operating budget in 2008 according to
this blog. There is all sorts of data on other urban parks
here from the Trust for Public Land.