SF's Presidio Coastal Trail closed indefinitely due to erosion


Hikers aren't the only ones being affected by the closure, there was a sort of chain reaction for cars and bicyclists. Everything's had to move away from the cliff's edge.

Was this a case of bad engineering or just bad timing? The three agencies involved here say they just don't know. No taxpayer money was used in the building of the project, but the NPS says it doesn't know if that will hold true for the repairs.

The pedestrian detour includes a climb over the guardrail. Traffic has been shifted to the east on Lincoln, where bicyclists and cars now have to share the road with no shoulders.

"It's not great for cyclists to have it narrow like this, right, because you know it creates very narrow space and you're basically forced to block car traffic to be safe, coming either way along here as a cyclist," bicyclist David Paschich said.

But the National Park Service says public safety is its number one priority here, where a segment of the coastal trail was closed in December.

The new and improved trail and overlook just opened in the summer. But after torrential rains, the trail started to slip.

Susan Purcell has been running here for 15 years. She says she knew this would happen and couldn't understand how the cliff could stay stable with all the old growth trees and vegetation being removed.

"You probably should have built it on the other side of the road and cut back here, because you could just have a crosswalk and go that direction and just leave the road here and leave that alone because it's going to slip," Purcell said.

The improvements were part of a $6 million project. The National Park Service says the engineering planned for natural coastal erosion, but the December rain was something else.

"They were saying it was a 30 year rain event, the first time in 30 years that this kind of rain event happened," NPS spokesperson Alexandra Picavet said.

A 60-foot segment of trail is closed. The park service dug out soil and rock as a safety measure. Monitors were installed to track soil and ground water movement, and an independent engineer has been hired to assess what to do now.

"Our engineers and the people who are looking at this trail want to see how water is moving through the area, was it drainage that needs to be address, or was it flow pattern that needs to be addressed," Picavet said.

The park service says repairs are delayed because the engineers studying this site need a lot of rain to see exactly what happens here in those conditions and well, it's been a very dry winter.

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