The costs for saving Healdsburg's historic Russian River bridge have gone down, but so have the costs of replacing it with a modern, concrete box girder.

Consultants on Thursday said the latest estimates to rehabilitate and retrofit the 1921, steel-truss span are about $10 million, which buoyed the hopes of those wanting to save the structure.

Cost of building a wider, modern bridge is now estimated at $16.6 million.

"Obviously rehabilitation looks like a very good option, and not just for preserving history," said Holly Hoods, a representative of the Healdsburg Museum. She said saving the bridge also makes sense from a cost perspective and in meeting community needs.

Several years ago a study had estimated the cost of rehabilitating the bridge at $13 million. And it placed the cost of a new concrete bridge — so abhorrent to preservationists — at $23 million.

Public Works Director Mike Kirn said the recession and the drop in construction costs is probably the reason estimates for both options have gone down.

In the end, the fate of the 1921 span could hinge not only on cost, but whether rehabilitating the bridge is eligible for federal funding.

Even if the rusting bridge is spruced up, made earthquake-safe and bolstered to withstand high flows in the Russian River, it still would be too narrow to meet modern standards. That means it may not meet the requirements for the 88 percent federal funding that which city officials want.

Once carried the sole highway span over the Russian River, it has become redundant since the freeway was built to the west along with a wider modern bridge. But it is cherished for its appearance and slower pace it affords for sightseeing and bicycling.

At a public meeting Thursday evening, some residents objected to even more expensive options being studied, ranging from $34 million to $49 million, that include keeping the old bridge and building a new one.

"It will have a huge impact (and) be totally out of scale," said Louis Bangham, who said a proposed roundabout at the end of a new bridge would funnel traffic to his neighborhood on Mason Street.

Consultants said some of the more expensive options are likely to be discarded.

"Some will be off the scale as far as cost and other considerations," said Ross Ainsworth of Omni Means Ltd. of Roseville, the transportation and civil engineering firm that was awarded the preliminary $2.8 million contract to study and oversee the bridge project.

Deciding what to do with the 89-year-old span, known as the Healdsburg Avenue Bridge, or Healdsburg Memorial Bridge, is one of the top priorities of the City Council.

Whether to fix or replace it has been a topic of debate for years. A 1979 Caltrans report gave the bridge the poorest rating of any in the county. But that was revised two years ago after it was discovered the agency had miscalculated the location of the pins on the truss connections.

Caltrans then said the bridge can bear all legal loads, including up to four semi-trucks and trailers at once.

A consulting engineer's report released last month basically affirmed the improved rating for the bridge.

But the bridge still doesn't meet width and height requirements. Questions also have been raised about its ability to withstand floods and earthquakes.

Last summer, Healdsburg obtained nearly $1 million from Caltrans and in federal highway funds to conduct engineering and environmental studies to determine how to address issues surrounding the bridge.

Consultants have come up with more than a dozen possibilities based on public input, almost all of which result in preserving the span in one way or another.

They include doing nothing or converting it to pedestrian and bicycle traffic only.

Another option is to rehabilitate the bridge and convert it to one-way traffic. A variation is to alternate the one-way direction, controlled by a traffic signal.

Also being considered is widening the existing bridge. Other concepts include replacing it with a similar style bridge or perhaps a newer style bridge.

Finally, the consultants say the existing structure could be moved to the south of a new bridge.

Consultants plan to reach an ultimate recommendation using criteria that include historic preservation, public safety, environmental sensitivity, right-of-way impacts, design standard conformance, cost and funding capability.

Another public meeting is scheduled for Aug. 26 where more analyses are expected to be released.

City staff and the consultant team intend to make their recommendation to the City Council on Sept. 7. The council is then likely to choose a favored concept, which will be subject to environmental studies expected to take at least a year to complete.

More details and photo illustrations of the options are available at www.healdsburgbridge.com.