By Allen Martin

SAN FRANCISCO (KPIX 5) – The latest bump in the road to remove the old Eastern Span of the Bay Bridge is something so small, you can hold it in your hand.

Caltrans’ plan was to save money and protect the environment by bringing down the old bridge piers with explosives. But once again, the agency finds itself taking a detour, for one specific fish.

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“The longfin smelt is on a countdown to extinction,” said Jon Rosenfeld, a conservation biologist with the Bay Institute.

The palm-sized fish is in big trouble. Rosenfeld told KPIX 5, “The longfin smelt, combined with the delta smelt and the Chinook salmon really demonstrate that this is a system wide collapse.”

Just three weeks ago, Caltrans announced that it wants to remove the old Bay Bridge piers with a series of small explosions beneath the bay, a sort-of mini-implosion they describe as more bay friendly and less expensive.

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“So we can really minimize the impact of wildlife,” Caltrans engineer Brian Maroney said. “And we’re done in about six seconds.”

But now, the California Department of Fish and Wildlife wants to make sure that cost-effective implosion strategy won’t cost the lives of too many smelt.

This isn’t the first time the demolition has run into wildlife concerns. Protecting birds on the old bridge has already added millions to the demolition price tag.

“Implosion at the Bay Bridge could be a knife wound for this fish. The lack of flows coming through the Delta and into the estuary is a shot to the head,” Rosenfeld said.

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The Department of Fish and Wildlife said they are reviewing the permit application, and we’re told it will likely be approved. What we don’t know is if smelt concerns will deliver a larger price tag, and remember the lower cost was one of the selling points for bringing out the explosives.