How an ‘ancient landslide’ keeps threatening a railroad, homes in San Clemente
SAN CLEMENTE — On Feb. 28, 1872, the San Simeon River crested at the flood level of 5.13 feet, the highest it has been since 1907.
At the same time, it dropped by more than 2 feet in an area about 2 miles south of Del Mar, where land was taken over by a railroad company. In the months that followed, that land was filled with water from the river, causing the river to recede and the elevation to drop, leaving homes in the area dangerously exposed. Some of those homes may have been more at risk than others because of the differences in soil types, or because of the fact that some were located along the San Simeon channel, which is where the river first crested.
After the city began moving residents into the flood-prone area, the water began to recede enough that the local Army Corps of Engineers was able to begin to flood the area again, this time at a much lower level. The agency says that is what the first of six levees and berms meant to protect the city were made for. The levees are still there today, but the berms that form them have eroded. And the creek that once swelled and then receded in the area has been cut off in places.
Now, in mid-May, after six weeks without rain, the stream has begun to grow again, and the local National Weather Service issued a flood warning for the city and its surrounding areas. The agencies are asking residents to be on the lookout for an “ancient landslide” on the San Simeon River.
“The historic river may be starting a new phase of flow,” the weather service says. “A large landslide or mudslide, could be at an end or potentially in the process of forming.”
This comes after six weeks of torrential rain. And in the meantime, the city has been getting by with only a third of normal water use, which is necessary because of its unique drainage channel, which flows through the hills in
