The challenge for non-profit news sites is that national and local foundations may be willing to help them get off the ground, but at some point they want them to be self-sustaining. Will readers of a site like the New Haven Independent give money on a continuing basis — a model well-established in the world of public television and radio stations?

Independent founder and editor Paul Bass intends to find out. Late this afternoon he posted a fifth-anniversary message, asking readers to choose a voluntary subscription of $10 or $18 a month (or more) in order to support an operation that has grown to a nearly $500,000 annual budget with six full-time reporters, several part-timers, affiliated sites covering Branford and the Naugatuck Valley and a State House reporter. Bass writes:

Five years ago today, the New Haven Independent hit the net with a new idea: completely local multimedia online-only professional news reporting focused on city news and issues, with reporting used as a springboard for wide-ranging community discussion. Not a “newspaper.” Not a radio or TV news program. A journalism-driven online urban community….

Cities like New Haven are returning to the “good old days” of multiple local media outlets where readers can find news, weigh in, and obtain different takes on what’s happening at home. No longer can a corporate monopoly control and choke off the flow of news and debate in one community.

Unlike, say, WGBH or WBUR in Boston, the Independent serves a poor, largely minority urban community. Bass’ challenge is very different from that of a public broadcasting executive appealing to affluent, well-educated viewers and listeners.

The Independent will celebrate its fifth birthday at a party on Sept. 15. I plan to be there. It will be interesting to see how many people turn out (57 have already said via Facebook that they’re coming) — and what level of support Bass is able to attract as he begins his sixth year.