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| September 06, 2021 Post 129 |
| A Visit To The Neighborhood Bar |
Barrier bars and islands have been in the news since hurricane Ida’s assault on the Louisiana coast. People are drawn to these scraps of land and on the coast they pay five figure insurance premiums to stay there. Here on Lake Ontario, both Irondequoit and Sodus Bay have barrier bars encrusted with houses. Yet, like the barrier islands of salt water, these are transient lands, remaining fixed only by constant inputs of tax payer funded stabilization.
I have sailed Lake Ontario’s waters for more than fifty years. But well before I became a sailor I was a beach comber. I believe the pastime of the shell seeker’s slow stroll and the pebble picker’s pounce upon a pretty prize, is embedded in our DNA. A million years ago our fore bearers scanned beaches in search of edibles- clams, mussels, tidepool crabs and perhaps a lucky freshly stranded still palatable find. Genetic studies suggest that seafaring humans spread to the New World across the narrows between Asia and Alaska and then worked their way south down the coast. So the irresistible attraction of the barrier bar or island is understandable.Birds and humans
But today our natural beaches are threatened by human actions throughout the Great Lakes and on our salt water coasts.
The living beach must move. Like a river, another sadly misunderstood and over engineered life giving landscape feature, the beach must change or die. Lake Ontario’s barrier bars are one of the most interesting and economically significant manifestations of this movement. And one of the most misunderstood.
Last year during that long quiet strange Covid summer I wrote a book, released by Arcadia Publishing this summer and now in bookstores, my Etsy Shop,( find it on sale at susanpgateley.com) and at Amazon. Among the topics I addressed was that of beaches and bars of gravel- something I first wrote about nearly 20 years ago. I have since learned more about sediment budgets and ‘cells’ of
Barrier bars protect the productive nursery areas of the lake and create favorable environments for both recreation and real estate development. that’s why recently the feds spent 9 million on habitat restoration by recreating the barrier bar that once protected Braddocks Bay. They are about to do the same on Blind Sodus Bay where a remnant of the bar now serves a thriving cormorant colony.Earlier this summer several hundred nests were evident here in the cottonwoods and willows.
The south shore of Lake Ontario has a half dozen large embayments. All were originally protected from the lake by barrier bars that periodically opened to allow exchanges of water and life between bay and lake.
Aerial photo of bar
These protected areas have huge significance to the lake’s over all ecology. The vast majority of our fish species depend on the warm sheltered sunlit shallows in their first year of life.Other creatures ranging from midges and turtles to cormorants and wood ducks also use these sheltered nursery waters. No multi-million dollar trophy fishery would exist here without the lake’s near shore wate
And we who sail and cruise the lake also depend on these protected waters for safe harbor.
When Europeans arrived and saw the bays they saw ideal anchorages for shipping. Towns like North Fair Haven and Sodus Point soon sprang up and became active ports with stabilized channels. Hundreds of thousands of tons of cargo were transported from coal trestles and lumberyards and grain elevators. Jetties and seawalls were built and the hardening of the shore began.
Historically sediment eroded mainly from shoreline bluffs and became the beach. It was moved by wave action mainly from west to east. However human activity soon disrupted this movement. Jetties blocked the movement of sediment from forming beaches, while open channels served as “sinks†that routed the gravel and sand into the bays. Once it settled here in protected water out of reach of the wav
Engineers call beaches and gravel barrier bars “protective features†for good reason. When a wave hits a beach its energy is absorbed. Pebbles move around, and shift and the shoreline behind the beach remains more or less intact.
When there is no beach, erosion accelerates dramatically. When people harden the shore line with seawalls or rocks they cut off much of the remaining sediment transport. Neighboring properties then lose their beaches.
The photo above shows the historic barrier bar at Blind Creek before the 2017 high water when the creek would fill up after heavy rains, break through the bar and then seal off again with new gravel moved by wave action. Sediment transport is dynamic. Once the bar was lost and a wide opening formed in 2018 th creek reached a new ‘stable’ state . Blind Sodus Bay also lost itâ€
State funded REDI money mostly has gone into hardening to promote the current concept of “resilience†but hard engineering has its limits. On salt water coasts we spend tens of millions of dollars annually on pump and dump programs to replenish sand which soon washes away again. After hurricane Ida hit Grand Isle its 52 million dollar surge protection barrier was quickly breached.
There is another way.It involves working with Nature’s forces to protect natural beaches both along the lake shore and on protected bay shores. See willow in 2017 Blind Creek bar photo). In Fair Haven you can see a row of willow trees at the state park along with a shoreline shrub called false indigo. These I suspect were planted many years ago and have done a good job of stabilizing the bay shore here. The network of roots stabilizes gravel and sand and is able to withstand the lower energy wave action generated by wind and boat wakes on the bay. Vegetation in the form of shrubs and wetland plants is effective as a “soft†defense of erosion on protected bays.
Even on the open lake ‘soft’ stabilization can slow land loss. As the eroding shoreline recesses and the barrier bars move inland, undercut willows often flop over and then re-sprout. They ‘walk’ inland with the barrier bar and help hold it together. They protect the precious natural nursery areas so key to the overall lake’s eco system health.
On salt water people are beginning to use natural stabilizing to defend against coastal erosion. Mangroves and sea grass on dunes are planted to hold the line. Oyster bars serve as effective underwater breakwalls that enhance marine nursery areas. Here willows,various wetland shrubs and shallow water emergent vegetation could do the same. If we allow it.
For more on natural soft stabilization there are many good publications on line. check out Shoreline Stabilization Handbook for Lake Champlain by the U of Vermont and Lake Shoreline Stabilization Parkland County https://www.parklandcounty.com/en/live-and-play/resources/Documents/PRC/iceheave/Shoreline-Stabilization-Sample-Plans.pdf