It'll never be the Thames, but downtown Tampa's Hillsborough River waterfront will begin to look more like a significant cultural and recreational attractor within a year or two. As Mayor Iorio's Riverwalk project inches along, the Tampa Bay History Center nears completion (scheduled for December) and the new Tampa Museum of Art's steel frame rises within Curtis Hixon Park. If the designers' renderings are to be believed, Bay area residents should be enjoying a flourishing waterfront that extends from Channelside to the Tampa Bay Performing Arts Center by 2010.

That prospective pleasure makes it easier to forget — finally! — the bitterly fought site wars that raged after the city's decision in 2005 to pull the plug on a too-expensive design for a new TMA by starchitect Rafael Viñoly. Following Iorio's polarizing suggestion to relocate the museum to the old federal courthouse and a brief plan to house it in Rivergate Tower, Curtis Hixon Park (site of the museum's original building, aka, Square One) re-emerged as a location that appealed to both the mayor and the museum's board of directors. At last, earlier this year, construction began.

Now, as California-based architect Stanley Saitowitz's 66,000-square-foot building sprouts from the ground, the TMA writes a cathartic postscript to the conflict over the museum's site with the exhibit Site Matters. Devoted to four proposals for site-specific sculptural installations at the new TMA, the exhibit teems with enthusiasm for the institution's new home and a desire to engage the community. Of the four proposals, three are produced by locally based artists — Joe Griffith of Tampa artist collective Experimental Skeleton, Leslie Fry of St. Petersburg, and artistic partners Carol Mickett and Robert Stackhouse, also of St. Petersburg. The fourth, by Maine-based Michael Shaughnessy, proposes a collaborative project between artist and community, perhaps making it, paradoxically, the most "local" of all.

Curator Elaine Gustafson culled the four proposals from about 10 submissions in response to an invitation to compete sent out to around 20 artists — a mix of people based locally and around the world. Now comes the hardest part: choosing at least one (and possibly more than one) of the proposals to build once construction on the new building is finished. Though the exact details of the selection process have been rendered uncertain by the recent arrival of the museum's new executive director, Todd Smith, public input will play a role (even if only in the form of a comment book prominently displayed in the exhibit).

After all, part of Site Matters' raison d'etre is to jumpstart the community's relationship with the new museum, even as the TMA keeps chugging along in an interim West Tampa outpost — a location that has failed to match the visitor volume of the downtown location, even with the enticement of admission by donation.

"We were planning the exhibitions for this interim space, and it seemed like a great opportunity to get the artistic community to really engage with the new building while we were in the interim facility," Gustafson says.

Here's what's on the table:

If St. Pete collaborators Carol Mickett and Robert Stackhouse have their way, the new TMA's atrium will house their story-and-a-half sculpture designed to simulate the experience of walking through water. Inspired by the museum's riverfront location, the artists plan to construct two upright forms (reminiscent of Stackhouse's previous work based on ship hull shapes) made of blue-green glass panels supported by wooden frames. Visitors could walk between and around the forms in the museum lobby.

Fry's plan calls for building a larger-than-life Sphinx-like sculpture inside the museum that would double as a theater for a video art piece based on the TMA's antiquities collection. This proposal stands out for its attempt to connect the museum's strength in Greek and Roman artifacts with its commitment to contemporary art. (In fact, the installation would be constructed between the contemporary and antiquities galleries on the building's second floor.)

Griffith's design for an outdoor sculpture may be both the most playful and the richest in symbolism. A snail or shell-like coil of the Bayshore Boulevard balustrade would sit outside the museum on the waterfront, in conversation with the terminus of the world's longest continuous sidewalk at the Platt Street Bridge. The ethereal watercolor paintings Griffith uses to illustrate his creative process — centered on the history of the baluster and the roots of its shape in the flower of the pomegranate — may give him the edge in presentation.

Finally, Shaughnessy proposes building a monumental sculpture with hay — a material he sees as quintessentially populist — with the help of Bay area residents. Paintings atop a digital rendering of the new museum's atrium show various possible outcomes, while photographs showcase similar past projects accomplished by the artist.

I swear I'm not pandering when I say that any of these proposals would make excellent additions to the museum and the local visual arts landscape. Given Stackhouse's status as a local son (born in New York but raised in Lakeland) turned international art icon and his exciting new collaborative union with Mickett, it's hard not to root for them; same for Griffith, a true pioneer within Tampa's arts community; or Fry, a formidable sculptor with impressive public art credentials. And Shaughnessy's hay sculpture? It could be just the community outreach needed to seed the museum's future growth.

Thankfully, we've got a lock on the TMA's new site. The only bone of contention now should be which of these wonderful projects to build there.