Here’s why dump trucks are moving tons of sand down San Francisco’s Ocean Beach

Nov 23, 2016

An unusual scene has been playing out at Ocean Beach over the past few weeks.

Huge dump trucks hauling loads of sand from the north end of the beach, near the Beach Chalet, two and a half miles down the Great Highway to the south end of the beach, at the fast-eroding intersection of Sloat Boulevard. It’s just one battle in a war between man and Mother Nature that’s been going on at the beach for decades.

 

“We're going to do about a thousand truckloads in the course of the next few weeks,” says Jean Walsh, from the San Francisco Public Utilities Commission (SFPUC).

The goal is to move about 37,000 tons of sand.

A constant battle

The SFPUC is using the sand to protect a water treatment plant it operates down near Sloat Boulevard. There’s a pipe there that releases treated wastewater into the sea. The sand surrounding the pipe plays a big role in protecting it from being battered by waves, but the ocean currents have a habit of sweeping that sand miles away, all the way up the beach to where Walsh and I are standing. That leaves the area around the plant vulnerable.

“A couple weeks ago we saw another four feet of that parking lot at Sloat fall off the cliff,” says Walsh. “So it's just a constant battle.”

It really is a battle. There are even ruins. The erosion has exposed a couple of old seawalls and the remnants of a pedestrian tunnel, built about a hundred years ago. Artifacts from times we’ve tried to hold off the sea – and failed. But in the case of the sewer plant, we can’t give up.

“We would never let this happen, but worst case scenario if that [pipe] was exposed and somehow ruptured, then we'd have a sewage spill into the Pacific Ocean,” explains Walsh.

 

The wastewater plant was built in 1993. Soon after that, the city noticed the erosion problem and responded aggressively, installing concrete barriers around the pipe and along the beach. The barriers did protect the pipe, but environmentalists and beach visitors weren't happy about the jagged blocks cluttering the shoreline. Meanwhile, storms continued to ravage the coastline south of Sloat. So the city tried to get a permit to build more barriers, but the California Coastal Commission denied it, saying they needed a new strategy. Hence the dump trucks, which first showed up in 2012.

Pierre Braganza, who grew up in the Sunset District, says he doesn’t remember the city doing this when he was younger.

“I've been out here my whole life and it's funny because the stairs — I remember as a kid you used to run down these stairs and it was kind of long,” Braganza says.

These days, you don’t even need the stairs sometimes because the sand piles up so high.

“I guess you got to be a little bit proactive or else nature will probably just take over everything,” says Braganza.

A lot of this area actually used to belong to the sea. Early San Franciscans pushed the beach about 200 feet west to level out dunes and make room for the Great Highway, the road that runs parallel to the shoreline. And ever since, the ocean has been trying to advance its way back — eroding the land under the road or covering it with enough sand that it often needs to be closed and cleared out during windy months. The city knows this, which is why the dump trucks are a temporary fix.

 

Options for the long-term future

The permanent solution requires tough choices.

 

“You can have free-flowing traffic, you can have a wastewater infrastructure system, and you can have a sandy beach,” says Benjamin Grant, Urban Design Policy Director for the city planning think tank SPUR. “You can have any two of those three, but you really can't have them all.”

Grant’s landed himself in the position of Commander-in-Chief of San Francisco’s long-term battle plan against erosion. For the past five years, he and his army of SPUR staff have been concocting a strategy that takes everyone’s needs into account: environmental agencies; beach visitors; and wildlife. It’s called the Ocean Beach Master Plan.

Grant says there are three main tactics to choose from when confronting erosion. The first is called “coastal armoring” and is similar to what the SFPUC already tried with the concrete barriers.

“That stops the erosion but also often degrades the landscape or the beach,” says Grant.

The second tactic is a full-on attack: padding the beach with a lot more sand to make it wider and hold off the ocean. That’s like what the dump trucks are doing – not a good long-term solution. So, SPUR has landed on a third option: a “managed retreat,” which Grant says means “re-aligning threatened assets away from the erosion hazard.”

In other words, we’re giving the land back to the sea, or parts of it anyway.

A national model

The plan suggests that the problem stretch of the Great Highway, south of Sloat Boulevard, should be removed as soon as 2020. Traffic should be rerouted and the area turned back into a natural coastal landscape. There will still be some protections around the water treatment plant, but they won’t need to work as hard thanks to the other adaptations.

At least, that’s the idea. The Ocean Beach Master Plan is a series of recommendations that all need to get their own green light by the city or the California Coastal Commission – or for some of them, both. Grant says that’ll take work, but if it gets passed, it would be huge.

“The Ocean Beach Master Plan is one of the first examples of a specific location having a detailed long term climate adaptation plan,” he says.

That means it could become a model for other areas.

“What we see at Ocean Beach today is a condition that we're likely to see much more broadly in 50 and 100 years,” says Grant.

The science supports this. A recent study found that seas rose at a faster rate in the last century than in any of the 27 before it.

 

“So if we can develop the tools and techniques and planning processes to adapt at places like Ocean Beach,” Grant says, “we'll be able to apply those tools much more broadly as the serious consequences of sea-level rise set in."

At Ocean Beach, Jean Walsh from the San Francisco Public Utilities Commission says she’s on board with the plan and ready to retreat.

“We're saying, let the ocean take what it wants and let's bow out gracefully and put our road back there where it's safe, and we don't have to fight this battle every year,” she says.

In other words, Mother Nature is winning the war right now, but Walsh is hopeful that a truce is on its way.

“After a lot of money spent and a lot of thought put into it,” she says, “hopefully we'll come up with a long term plan that works for everyone.”

Including the the ocean.

 

 

To read the Ocean Beach Master Plan, click here.

Work is expected to continue at Ocean Beach through December.

 

 

This story originally aired in March of 2016.