coastal edge

April 6, 2014 in nature, things built

Here in southern California, in January, we had a few days of heavy rain, a large swell, and high tides – all at the same time.  On the Sunday after one of the storms, my husband and I rode our bikes on the path at Bolsa Chica State Beach, to check out how the beach had weathered the conditions.  At some spots, the ocean had eroded the beach to the base of the lifeguard towers.  There used to be thirty to fifty feet of beach between the towers and the edge where the beach dropped off to the tide line.  Along some areas on the path, we had to walk our bikes.  The waves had pushed sand and debris onto the paths; the sand was about six inches deep, too much and too soft for our wheels to roll over.  The swell was still here.  About a mile offshore, waves were still breaking – a rare sight here.

Eight years ago, at the southern end of this beach, a tidal inlet was created to connect the Bolsa Chica wetlands with the ocean.  As part of this project, since the inlet cuts across Pacific Coast Highway, a new bridge was built for traffic and pedestrians.  About twice a week, I stop on this bridge.  There’s always something happening or new to see:  the tide flowing in or out; sting rays and small sharks; people fishing, surfers riding waves into the inlet and sometimes under the bridge.  There is a jetty, made with large boulders, to keep the inlet open.  It’s about 350 feet wide.  Around the time of this last storm, the inlet was about fifty percent open.  Over the years, the ocean has been gradually depositing sand onto the north side of the inlet, creating a small beach.  Since the most recent storms, this beach has been growing at an accelerated pace.  This weekend, the inlet’s opening is about twenty percent of its original width.

The shoreline, where water and land meet, is a fragile, dynamic edge.  It’s always changing, in spite of our efforts and desire to make it last.  At this edge, a lot of energy:  winds, currents, tides, waves, chemical interactions between elements in the water and in solid materials – to list a few things.  These forces carry away land and deposit it to another area along the coast.  Sometimes, they carve sculptures into the land.  The cycle of tides creates special environments where certain creatures and plants thrive.  Over time, this weathering builds up and takes away layers, leaving a patina.

 

erosion 1

under the bridge at the tidal inlet

 

 

erosion 2

 

 

erosion 3

 

 

erosion 4

 

 

erosion 5

 

 

erosion 6