THE MID-COUNTY POST
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Coastal Commission Approves Vast Seawall along East Cliff Drive
After Decades of Debate, Roadway Will Likely be Saved
A section of the sculpted concrete seawall already in place at Pleasure Point.
By Michael Thomas
For decades, the ocean has slowly devoured East Cliff Drive along the Pleasure Point neighborhood. At times, the world-renowned surfing waves merely nibble at the crumbling bluffs beneath the road and the popular pedestrian corridor. At other times, storm swell takes ravenous bites out of the Purisima sandstone, and chunks of pavement suddenly collapse.
After years of hand-wringing over the fate of public access and buried utilities, the ambitious plan to encase 1,400 feet of the bluffs in a shell of concrete is finally moving forward.
At a meeting in San Francisco on Dec. 13, the California Coastal Commission approved the seawall plan developed by Santa Cruz County’s Redevelopment Agency (RDA) and its former application partner, the U.S. Army Corps of Engineers.
For the first time, it appears virtually certain that Santa Cruz County will be building one of the largest seawalls on the Central Coast. Many have worried about how such a structure might impact the surf, the tidal beach at the base of the wall and the coastline as a whole. Soon all that speculation will give way to real-life observation as a major experiment in coastal armoring begins.
An 1,100-foot seawall will be constructed between 33rd Avenue and 36th Avenue, followed by improvements to the pedestrian thoroughfare from 32nd Avenue all the way to 41st Avenue.
In the final stage of the project, a 300-foot seawall will be built where 41st Avenue meets the coast, otherwise known as The Hook. The entire project is expected to cost more than $8 million.
Commission Satisfied with New Studies
RDA Project Manager Betsey Lynberg is confident that the experiment will be a success.
“I feel that this approach we are using is so far superior to other bluff armoring methods,” she said.
The wall will be sculpted and textured in a style that many associate with Disneyland architecture, with narrow, man-made goat trails and ledges to support patches of native vegetation.
For an example of this construction technique, check out the emergency repairs completed in 2004 near 34th Avenue. They’ve been carefully camouflaged.
The Coastal Commission approved the seawall along with a plan to overhaul the coastal walkway, access stairways, and the small park near Elizabeth’s Market.
“[It] combined the two projects “” the seawall and all these recreational improvements,” said Dan Carl, Central Coast District Manager for the Coastal Commission. “I think that helped make it more warranted and palatable to the Commission.”
The vote to approve the project was unanimous, although only seven of the twelve commissioners were still present at 7:15 p.m. when the decision was made. Giving the project a green light represented a major shift in the commission’s stance on the project.
Commissioners rejected a nearly identical plan in November of 2003, demanding that the county clearly demonstrate the urgency of the situation and evaluate alternatives more thoroughly.
“Since that time, the county spent a lot of time working on studies to show how the road might be undermined,” Carl said. “They really did their homework.”
A consultant evaluated the roadway in 2005 and reported that 65 percent of the bluffs in the project area were failing or in immediate danger of collapse.
As in most of Santa Cruz County, erosion claims an average of 8 to 12 inches of bluff every year. As a condition of approving the project, the Coastal Commission requested changes in several areas, asking for better drainage and treatment of runoff, wood fences and benches, and native plants in the landscaping.
“We are trying to keep it as natural and low-key as possible,” Carl said. “This isn’t Los Angeles. You don’t want to see a big concreted right-of-way.”
While the seawall will extend the life of East Cliff Drive for decades, it’s impossible to predict exactly how it will change the cherished stretch of coast.
“It was difficult to see how this wall would affect the surf break,” Carl said. “Since the shoreline won’t be eroding anymore, that beach is going to disappear over time. From our perspective it just made sense [to build it] at this time, but there was certainly a tradeoff.”
Will Pleasure Point Ever Be the Same?
At the Coastal Commission hearing, Mark Massara, the Sierra Club’s Coastal Program Director, offered dire warnings about the cumulative impact of coastal armoring. He suggested that structures such as this one threaten the very existence of sandy beaches in California.
Massara believes the county was just going through the motions when it evaluated planned retreat to satisfy the commission.
“The county came back and said it’s too expensive,” Massara said. “The $28 million that they estimated it would cost to start buying up property and planning a retreat may have been the best alternative.”
He believes that the Coastal Commission, which has seen a shift in membership since 2003, simply capitulated under continued pressure from the county.
“What kind of message does that send in the face of global warming and sea level rise?” Massara said.
According to conventional wisdom regarding seawalls, you can’t defuse the power of the ocean “” build a seawall in one spot, and it shifts wave energy and erosion to the nearest unprotected bluff.
Create a hard wall to reflect waves, and they’ll carry away beach sand. Gary Griggs, a UCSC coastal geology expert who consulted with the RDA, said new research has undermined some of the old assumptions.
In 2005, Griggs led a team studying the long, austere seawall at Via Gaviota near Seascape. The wall was built in the 1980s, when less emphasis was placed on the aesthetics of bluff protection structures.
“People have for years said that seawalls cause beach erosion,” Griggs said. “It turns out we never did see any difference between what was happening there [at Seascape] and on nearby beaches.”
His findings suggested that, in some cases, seawalls might not disrupt the accumulation of sand as previously thought.
“That surprised me, and I think it surprised the Corps of Engineers,” he added.
However, loss of sand at Seascape could be masked by the huge amount of incoming sand carried by near shore currents, called littoral drift.
Along Pleasure Point, there’s also a massive amount of sand moving down the coast. Griggs estimated the littoral drift there at 300,000 cubic yards a year, or 30,000 small dump trucks of sand. However, most of that sand drifts by without stopping. From Pleasure Point to New Brighton, the current is moving at a right angle to the coast, so sand is carried right past the shore unless there’s something there to stop it.
Griggs also sought to dispel the notion that waves reflected off the seawall would carry away sand.
“There is no difference between concrete and the Purisima [bedrock] in terms of how it reflects waves,” he said. “The reflected wave hits the incoming wave and that energy is dissipated.”
What Will Happen Next Door?
Wetsuit pioneer Jack O’Neill’s house is one of only a few homes remaining on the ocean side of East Cliff at Pleasure Point. The home is perched on a bunker foundation over the surf, protected by a small pile of riprap.
When County supervisors approved the latest seawall plan in March, O’Neill told them he didn’t expect his home to last forever, but he didn’t want the seawall to make things worse. Lynberg said that RDA planners have been in regular contact with engineers hired by O’Neill to develop a plan for his home.
“We are all agreeing about what needs to be done so this project doesn’t impact his house,” she said. “We are going to need to rearrange some of that riprap where this wall meets his property.”
East Cliff veers inland after O’Neill’s home, and the wide expanse of bluffs there will be one of the last unprotected stretches in Pleasure Point.
If seawalls do, in fact, deflect wave action to the nearest unprotected piece of coast, O’Neill’s house and the bluffs beyond could see accelerated erosion. Griggs said that without protection along the coast, erosion will occur.
“Clearly that area will [erode],” he said of the open space beyond O’Neill’s house. “In 50 years, that cliff should move back 25 to 50 feet.”
However, he doesn’t think the seawall will hasten its retreat, again referencing the study at Seascape.
Waves May Actually Grow
In the 10 years since the plan emerged, there’s been constant debate over the fate of Pleasure Point’s famed surfing waves. To better understand the break, US Geological Survey researchers filmed the waves for a full year and mapped the locations of wave peaks.
They determined that the wall won’t destroy them. But Griggs points out that the break will evolve, wall or no wall.
“The way the surfing community is, they want it to be the same waves that they surfed when they were growing up,” he said.
But that’s never guaranteed.
“The earth is not a static museum. We can’t hold everything constant.”
The looming threat of sea level rise guarantees that there will be changes. However, new research implies that the waves are actually growing. Most estimates of sea level rise predict an increase of about 1.5 inches per decade.
USGS studies of Pleasure Point indicate that such an increase would bring the wave breaks six feet closer to shore every 10years. That could go unnoticed for some time, since the wave locations vary from month to month by up to 200 feet.
There’s another factor at work as well. Griggs said new research on the Pacific Coast shows average wave heights are increasing by about eight inches per decade.
Since larger waves break in deeper water, the growing waves could push the break back offshore, and then some. And they’ll be bigger.
Work May Start in 2008
According to Lynberg, the project will go out to bid as early as the fall of 2008 and construction could start soon thereafter. In the meantime, the design drawings still must be expanded into detailed construction documents.
Additionally, the Army Corps of Engineers and the Monterey Bay National Marine Sanctuary need to sign off on the portion of the work that falls below the high tide waterline.
For some Pleasure Point homeowners, the project couldn’t have come sooner.
“We are pretty excited about it,” said Keith Adams of the Coastal Property Owners Association of Santa Cruz County.
Adams lives on the bluffs next to the Hook, adjacent to the southern segment of the proposed seawall.
“Our organization was formed in 1967 to specifically come up with a solution to save East Cliff Drive,” he said. “After 40 years, it has finally come about.”
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