David Cohen, co-owner of ProMet Marine, on Allens Avenue in Providence, stands amid ships his company is repairing.

The Providence Journal / Andrew Dickerman

PROVIDENCE — The future of the city’s industrial waterfront could range anywhere from 10-story condo towers to a dramatic expansion of the petroleum shipping in place now to an abundance of 6-story office towers, a consultant studying the waterfront has concluded.

The city is in the midst of a four-day charette examining the future of its waterfront, and for the first day yesterday, city-commissioned consultant Local Architecture Research Design presented four possible scenarios for the long-term future of the city’s industrial waterfront along Allens Avenue.

At the charette, players on both sides of the issue are attempting to hammer out whether the Allens Avenue corridor should stay strictly industrial, or whether the zoning should be changed to allow residential uses along the stretch north of Thurbers Avenue.

Mayor David N. Cicilline supports changing the zoning. The existing businesses there are fighting him, fearful that the introduction of residential development will lead to the death of heavy industrial business.

Charlie Cannon, of the consulting firm, laid out four likely scenarios: the continuation of the status quo of existing industrial business; the introduction of office and commercial buildings; the introduction of residences; and the dramatic expansion of maritime-related business.

If the existing businesses remain and expand somewhat, it could mean 200 to 300 more jobs over the next 10 to 20 years. Several four- to six-story buildings might be constructed as these businesses create more space for offices, light manufacturing and warehousing.

If the zoning changes to mixed use and serious office development comes to the area, the character of the waterfront could change significantly.

Office buildings rising four to six stories could be built along the waterfront, perhaps a total of 300,000 to 600,000 square feet of office space, Cannon estimated. These structures could house — but not create — between 2,000 and 3,000 jobs, in high-level Class A and B office buildings, Cannon estimated.

Some limited retail and residential would be possible also, he said.

It’s likely those commercial developments would come in incrementally as the need arose, probably in buildings approximately 70,000 square feet. Parks and public space would join the commercial structures.

If the waterfront goes the heavily residential route, Cannon’s study predicts 6- to 10-story condo or apartment towers, offering from 50 to 200 units each. They would be recessed from the waterfront to avoid hurricane and flood surges up the Bay, and also kept slightly away from Route 95 to the west, allowing only roughly 30 acres for realistic development, he said.

These units would sell for between $300,000 and $500,000, he predicted, and at that price, they couldn’t be too small.

“We’re probably seeing, still, a rather limited number of units,” Cannon said.

The residential scenario is championed at the moment by developer Patrick T. Conley at his Providence Piers site, set between Sprague Energy and ProMet Marine Services, a shipyard.

On the other side of Conley’s fence, brothers Joel and David Cohen run ProMet, and serve as de facto spokesmen for the Providence Working Waterfront Alliance, a group of industrial businesses in the area.

“While artist lofts may be socially desirable, and condominiums, and hotels, and office buildings, they don’t have to be located on the water, nor in an industrial neighborhood,” Joel Cohen said.

They support the fourth possible scenario: an expansion of the maritime businesses.

A serious maritime expansion would likely mean creation of 300 to 400 high-wage jobs, and the construction of several one- to two-story warehouses, support and small office buildings to handle the distribution of goods throughout Southern New England.

As it stands now, Allens Avenue is probably ill-prepared to handle the truck traffic that would come its way under that scenario.

“We would need to see significant infrastructure investment on the part of the city,” Cannon said.

To the Cohens, this is the best possible option. They say that if the zoning does not change, they would soon begin a $2-million to $4-million expansion, and three other waterfront businesses — J. Goodison Co, Walco Electric Co. and Narragansett Improvement — would also expand.

Some unlikely allies have come out to defend the waterfront businesses in the first day of the debate. For instance, Rich Fuka, of the Rhode Island Fisherman’s Association, yesterday opposed the zone changes specifically because of their effect on ProMet. He said that the Rhode Island fishing fleet needs the ProMet facilities for repairs.

“Losing the last marine service company in all of Rhode Island is just another spike in the coffin for the fishing industry,” he said.

Providence ranks as the 56th busiest port in the United States by tonnage, importing and exporting 9.26-million tons annually, ahead of much larger cities such as San Diego, San Francisco and Miami, according to 2006 data from the U.S. Army Corps of Engineers. Fall River ranked 98th, and Newport 141st.

The mayor has taken an active interest in the outcome of the charette, kicking off the discussions last night, and noting that he understood that some feel threatened by the discussions.

“I recognize that any time you talk about change — any kind of change — it raises concerns,” he said.

He said, however, that the promise of the waterfront is such that the city must explore all possibilities.

“It’s an area, I think, with enormous potential and great opportunities,” he said.

City Councilmen Terrence M. Hassett, Kevin Jackson, Michael Solomon and Seth Yurdin were also on hand.

The sessions continue today, starting at 11:30 a.m., with a session on mixed-use waterfronts elsewhere in the United States. At 2 p.m., a session on public access and public use is scheduled, and expected to be heavily attended. Tonight at 6 p.m., participants will delve further into the four scenarios Cannon laid out.

dbarbari@projo.com