February 13, 2014 Thursday

Stinson Beach Erosion

Yesterday Mary told me about the major erosion at Stinson caused by last week's four days of rain. This morning I was at Stinson collecting a water sample for Surfrider's water testing program and followed up on Mary's report, and she was right.

Check out the above photos. Water erosion took out a large chunk of asphalt from the northwest corner of the Park's north parking lot and cut a ten-foot deep gully through the sand to the ocean. On the left is the destruction to the surface of the parking lot, and on the right I turned around 180 degrees to capture the new ravine to the surf.

"We came this close to being flooded out," said Maxine co-owner of the Parkside Cafe pinching together her thumb and forefinger. Her husband John stated that it was not that bad. But John, Maxine and their two children spent hours stacking sandbags along the external wall of the Parkside Cafe and Snack Bar because of runoff overflowing the banks of Eskoot Creek that runs between their property and the main parking lot of the Stinson Beach Park.

Here's what happen, as told to me by a park ranger. Over the summer the Park Service built a berm along the park's side of the creek to keep water from flooding the park's main parking lot. A couple of months ago a slide high on Mount Tam near the source of the Eskoot Creek created tons of loose rock and sand. Four days of rain washed the rock and sand down the mountain filling up the flat part of the creek between the Parkside and the berm along the parking lot forming a small lake that was quickly rising. The chief of the Stinson Beach Fire Department alerted the county of the threat of serious water damage. The chief and county agreed that it was better to flood the park than the businesses along the creek. The county bought in a backhoe and took out the berm. The water poured into the main parking lot and flooded the north parking lot in two feet of water, sand and mud. The water broke through the northwest corner taking out asphalt and cutting a small canyon to the ocean.

"Is the park going to rebuild the berm?" I asked.

"Yes, but first they are going to dredge out the creek."  

A couple days later, the backhoe was back digging out the sand and rocks that washed down from the mountain. The sandbags at the Parkside are still in place and John and Maxine are lining their side of the creek bank with bricks.

Next time you are at Stinson, check out the remnants of this major storm's force.