THE CALIFORNIA DELUGE : Tides Pose New Threat to Beaches

After being pummeled twice within a week, the worst for Orange County’s beaches--some of them closed Wednesday because of storm-related sewage spills--could come this weekend.

That’s when extreme high tides are expected to coincide with more rainfall.

“We’ve taken a pounding,” said Larry Paul, the county’s coastal engineer. “Now that the beaches are exposed like they are, with no protective sand, this is setting itself up for some real problems.”

For the 40 miles of coastline in Orange County, this has already been a pulverizing 1995. First, earlier high tides swamped the coastline, then 10-foot-high surf pounded it, and then the two storms peppered it with urban runoff, including everything from tree trunks to shopping carts.

Among the worst hit so far are two narrow beaches--Aliso Beach and Main Beach--in Laguna Beach.

While most of the wide stretches of county beach in Seal Beach, Huntington Beach, Newport Beach and San Clemente can handle the poundings, Aliso Beach and Main Beach have been hit by the surf on the ocean sides and the runoff from the creek mouths on the inland sides.

“Just about everything you can think of is deposited there,” Mike Dunbar, general manager of the South Coast Water District, said of Aliso Beach on Wednesday. “You’ve got an incredible amount of debris from trees, dirt, plants, leaves. If we get more of this, who knows what will happen.”

A 1 1/2-mile stretch of Aliso Beach was closed late Wednesday when it was discovered that 250,000 gallons of raw sewage had spilled into Aliso Creek at the height of the storm Tuesday, according to county health officials. The spill was caused by a power outage at a pump station, officials said.

The beach will be closed indefinitely.

Main Beach has suffered several hundred thousand dollars in damage from the two storms, largely because of the runoff from Laguna Canyon, according to city officials. About 80 feet of the boardwalk has been torn up, as has the adjoining cobblestone walkway and a large section of Main Beach Park.

“This is probably as bad as Main Beach has ever been,” said Mike Dwinell, the city’s chief of marine safety. “It looks very dramatic.”

Also, a mile of beach on each side of the Santa Ana River mouth was closed late Wednesday following a report by the Orange County Sanitation Districts that 116,000 gallons of raw sewage had overflowed the sewer system and entered the street from a manhole at 3150 Harbor Blvd. in Costa Mesa.

The beach that has been quarantined extends from Superior Avenue in Newport Beach to Magnolia Street in Huntington Beach, including parts of Newport City Beach and Huntington State Beach.

Also, county health officials on Wednesday closed a half-mile stretch of beach between the mouth of the San Gabriel River and the Seal Beach Pier because it was polluted by sewage from two spills Tuesday at an overflowing manhole in La Habra.

In San Clemente, most of the city beaches have withstood the rains well, with the exception of some heavy erosion due to a storm drain at North Beach and a sewage spill at Riviera Beach, said city and county officials.

Riviera Beach has been closed since Sunday morning when an estimated 6,000 to 10,000 gallons of raw sewage flowed from a trunk sewer line that runs along the beach, said Larry Honeybourne, an Orange County health care official.

At the bottom of the Selva steps in Dana Point, the sand has washed away, leaving only a rocky bottom, Paul said.

“It’s not a wide beach to begin with, but because of the way it sits, the sand always washes away,” Paul said.

At Salt Creek in Dana Point, the beach has plenty of sand, but the debris--particularly kelp from the beds offshore--is piled high, Paul said.

In Huntington Beach, the heavy rains have caused some bluff erosion that closed a bike trail near the beach at Golden West Street, said Lt. Steve Davidson.

“This is not really a new thing, but when we have rains like we’ve had, it definitely accelerates the process,” Davidson said.

Times staff writer Leslie Berkman contributed to this report.