Sunday, April 19, 2009

Maxwelton





Mackie Park is having a bit of a crisis. A new spit forming updrift (south) and offshore of the current beach, has now extended past the end of the boat ramp and has pretty much starved the park of beach sediment. The spit has also created an interesting lagoon in front of homes to the south that previously had waves breaking on their bulkheads. The air photo on Google Maps is a couple of years old, but it shows the complexity of beaches in this area (click on title of this post).

The boat ramp is being undermined - the beach has dropped significantly on the downdrift side and has even dropped on the updrift side. Compare the
earlier post: Mackie Beach, March 2007. The beach in front of the park itself has also eroded significantly - although it always looked to me like maybe the old rock bulkhead reflected an earlier episode of the same process that is occurring today.

It's interesting to find a shoreline where rapid accretion is occurring - and even more interesting to find one where the accretion is causing problems. But the growth of a spit starves downdrift beaches of sediment just as would a groin or a beach mining operation. Growth of a spit like this may have been a contributing factor in the breaching of another spit (Henny's Spit) in the mid-1990s a few miles north of here near Sunlight Beach.

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