Sinkholes pockmark SF after storm

At least four sinkholes opened up on the streets of San Francisco following multiple days of heavy rainfall, utility officials said today.

The largest of the four sinkholes opened up Wednesday morning in the city’s Lake Street neighborhood, according to San Francisco Public Utilities Commission spokesman Tyrone Jue.

Large amounts of rainwater inundated the sewer system at Sixth Avenue and Lake Street, causing a storm drain pipe to break, Jue said.

Rainwater rushed beneath the surface of the street, eroding soil below and causing the roadway to cave in around 9 a.m. Wednesday, Jue said.

The sinkhole stretched about 20-by-30-feet across the roadway, SFPUC officials said.

Once the roadway caved in, both an 8-inch wide gas line and an 8-inch wide water line were damaged, leaving nearby residents without gas and water until about 3 p.m. Wednesday, Jue said.

PG&E crews responded to the intersection and capped the gas line and then provided residences with temporary gas connections. Temporary water line connections were also put in place, Jue said.

He said the sewer at that intersection was built from bricks more than 100 years ago and will be getting an upgrade during the repair process.

Jue said the sewer should be functional again by Friday and that permanent water and gas line repairs will be made over the weekend.

Repaving is scheduled to take place early next week and, if all goes well, the roadway should be fully reopened by Wednesday morning, Jue said.

Vehicles and pedestrians are still able to pass through the intersection while repairs are underway, he said.

Another sinkhole caused by the heavy rainfall was reported Wednesday in the city’s Corona Heights neighborhood, Jue said.

That sinkhole was located on Danvers Street near Market Street and was about the size of a small car.

Jue said the hole was not very deep and was located along the edge of the roadway near the sidewalk.

He said the sinkhole appears to be caused by a residential connection, as opposed to a sewer connection.

It has since been patched and will be further inspected, Jue said.

A sinkhole near Sigmund Stern Recreation Grove was also reported Wednesday and was relatively small, Jue said.

That sinkhole was located at the intersection of Sloat Boulevard and 19th Avenue and has since been patched up.

Jue said crews would soon conduct a thorough inspection at that intersection before repaving.

On Wednesday evening, a fourth sinkhole was reported in the Mission District near San Francisco General Hospital, but Jue did not know the size or severity of that sinkhole as of late this morning.