GUEST

GUEST EDITORIAL: The unintended, unknowable consequences of dredging Big Pass

Jono Miller
Sarasota Herald-Tribune

It seemed like a good idea, at the time. A little more than 12 years ago I was running for a seat on the Sarasota County commission and I published a blog post questioning dredging Big Pass for the sand accumulated in the ebb tidal shoal.

I don’t imagine my opponents (there were two) had thought much about it, and it wasn’t a high-profile matter at the time since the Corps of Engineers wasn’t going to show up to hold a hearing on the concept for another five years. I probably didn’t need to bring it up. But at the time, I thought it was worth weighing in on the issue.

Now, since it’s possible that the dredging may start within a month, I’d like to make it clear that I still think it is a terrible idea.

What tragedy will befall us if Big Pass is dredged? Unlike the Corps and the dredging proponents, I’m willing to say I don’t know. No one knows. No one knows because this pass has never been dredged and because it is part of a decidedly complicated system.

Will a second channel develop, causing more shoaling due to decreased water velocities? Maybe. Will it affect sand delivery to Siesta Key? Probably. Will that be noticeable? Hard to say. Will wave heights increase on pass-fronting properties? The Corps thinks so. Will landowners be able to prove it in court? Probably not. Will the dredging affect reproduction of spotted eagle rays and spotted sea trout? Most likely. Will that be documentable? Maybe. Sea turtle nesting? Maybe. Seagrass? Yup.

Will any of these become a big deal, worthy of newspaper headlines? No one knows. No one knows because no one knows where the inflection points are, where seemingly minor phenomena morph into positive feedback loops with unexpected consequences.

Will something happen that no one is thinking very much about? I’d say the likelihood is high. Why? Because despite assurances from engineers (and now computer modelers), we don’t have a great track record in anticipating problems.

Here’s one paragraph from that 2008 blog post: “Our county's past is strewn with projects that seemed like a good idea at the time and now, in retrospect, we're left wondering how our predecessors could have been so reckless. We blithely flattened Indian Mounds for road base, diverted and straightened Cowpen Slough, connected the Myakka River to Robert's Bay and removed unique geologic formations and archaeological treasures from Warm Mineral Springs. Some of these hindsight-inspired errors are irreversible; others are now demanding large sums of money to partially rectify. There is no small measure of humbling irony in the fact that many of today's problems were yesterday's solutions.”

Those local projects as well as the Cross Florida Barge Canal, straightening the Kissimmee River, and draining the Everglades all seemed like good ideas at the time.

Let’s reflect upon a couple of other local coastal projects, starting with the Gulf Intracoastal Waterway. It seemed like a good idea at the time to allow deeper-draft watercraft to travel in more protected waters. But it turned out to be the biggest negative impact on our bays, and it’s what doomed Midnight Pass. Maybe some engineer realized that diverting more tidal flows north and south would reduce the amount of water sloshing in and out of Midnight Pass, which, in turn would allow shoaling and littoral drift to gain the upper hand.

As the pass became more unstable and migrated north, threatening homes, at the time it seemed like a good idea to allow the homeowners to fill in the existing pass and relocate it back farther south. After several attempts, it became obvious that wasn’t going to work. Nice theory; impossible in practice. So in our quest to aid navigation, we lost a wonderful natural pass.

It may take years for any negative effects of Big Pass dredging to become noticeable. I may not be around. Some will never be known because we don’t know how the system would have evolved without dredging.

One thing is clear: If and when major problems develop, Sarasotans will be able to look back wistfully with heartfelt ignorance, and say: It seemed like a good idea, at the time.

Jono Miller, a Sarasota resident and longtime community leader, is a contributing columnist.