Philadelphia's new Delaware waterfront manager isn't supposed to choose a master planner until its Monday meeting, but in characteristic fashion, the politicians are laying the dynamite to sabotage the effort.

Monday's vote, when the Delaware River Waterfront Corp. will select one of five top-notch planning teams, should be a triumphant moment for the city. After decades of seeking quick salvation in developers' grand schemes, Philadelphia has finally become realistic about what it takes to build a viable waterfront neighborhood. With the hiring of a master planner, the city begins the unglamorous, but necessary work of laying out a street grid, setting building heights, and figuring out where to locate parks, transit, and key development projects.

The problem is that people like Gov. Rendell, Mayor Nutter and Sen. Arlen Specter can't bear to leave the planning to the planners. They've already endorsed a route for a new Market Street trolley to the waterfront without bothering to wait for the paid experts to study the matter.

Don't get me wrong.

Some sort of new transit line would do the Delaware good. PennPraxis, which conducted an initial waterfront study in 2007, envisioned a north-south trolley along Columbus Boulevard. The problem is the proposed Market Street link. Who's to say the master planner won't find a better way to tie the river line into Center City's transit network?

Given Rendell's obsession with riverfront gambling, it should come as no surprise that the proposed route is essentially a Streetcar to the Slots - a door-to-door connection between the Convention Center and the two planned casinos that is largely geared to tourists. The trolley would run down the middle of Market Street before turning onto Columbus Boulevard to serve the waterfront.

The $500 million project is still a gleam in the governor's eye, unfunded and unengineered. It's hard to believe the route could ever qualify for federal funding because the Market Street portion cannibalizes from two perfectly good underground services, the Market-Frankford and Subway-Surface lines. The feds hate wasting scarce transit dollars on duplication.

If you accept the notion that transportation is the key determinant of urban form, the mere act of drawing a trolley line on a map can't help but shape the master plan's conclusions, undermining the whole exercise. The city's own transportation planner, Anthony Santaniello, testified against the half-baked scheme.

You don't have to be a transit expert to find a half dozen other things wrong with the idea, the brainchild of the Delaware River Port Authority.

For starters, the trolley proposes to use the Los Angeles-style scissor ramps to leap over the canyon of Interstate 95. The Streetcar to the Slots would forever preserve that unfortunate ramp design when the city should be looking to blow them up.

You would think I-95 would rank high on the master plan's list of study items. But here again, the city has preempted the experts on a major transportation issue. The planners are being told to operate on the assumption that the highway is here to stay in its current form.

"Eyebrows are way up over both these decisions," said Steven Weixler, who chairs the Central Delaware Advocacy Group, which represents riverfront neighborhoods. Their view is that the master planner shouldn't be handcuffed by old assumptions.

Weixler happens to be among those who believe I-95 is overscaled and should be narrowed to two lanes south of the Ben Franklin Bridge when it comes up for a scheduled, federally financed reconstruction in a few years. Others want to use the occasion to eliminate that stretch altogether and reroute traffic onto Columbus Boulevard.

It's hard to say what's best because none of the options has been studied. We do know, however, that the highway's unbreachable gulf has long thwarted the waterfront's growth. How could the city undertake a master plan and not examine its highway options? The reconstruction is fast approaching.

It's odd that the Nutter administration would be so cagey on the transportation issues when it has been otherwise exemplary on waterfront policy. In the spirit of transparency, the administration last week helped organize a public discussion at Festival Pier with the five competing master planning teams.

Frankly, I didn't detect a single note of disagreement, though some boiled down the issues more succinctly than others, particularly Alexander Cooper of Cooper, Robertson & Partners, the firm credited with planning Manhattan's Battery Park City.

During those moments when my mind wandered (really, it was a fascinating event!), I realized we were all sitting on the answer to the waterfront's problems: the 16 city-owned acres of Festival Pier, located at the foot of Spring Garden Street.

In the entire seven-mile study area, Festival Pier is the only site that retains the remnants of a once-dense urban streetscape. It's just one block from the Market-Frankford El, the underrated transit treasure that spirits commuters in minutes to the city's two great employment nodes, Center City and the university area.

If you squinted a bit, you might think you were on Broad Street instead of on the river. Just imagine if a project like the Piazza at Schmidts in Northern Liberties had been built there. A development that had Schmidts' generous public space, shop-lined ground floor, and dense residential component would be a game-changer for the waterfront.

To think, all these years the city has assumed that its inaccessible Penn's Landing site at the foot of Market Street was the front door to the waterfront. The entrance was at Spring Garden Street the whole time.

There's no highway canyon to cross there. Spring Garden may even be the perfect spot to link a riverfront trolley into the SEPTA network. But that's something for the master planner to decide.

Contact architecture critic Inga Saffron at 215-854-2213 or isaffron@phillynews.com.