Turning the Tide on Seal Beach’s Grain Drain : Erosion: Santa Ana River sand is an almost perfect replacement--and 9,000 truckloads of it may soon be on the way.

In a cluttered laboratory near Long Beach Municipal Airport, 10 brass sieves sitting amid an array of soil-filled bags hold a key to the restoration of this city’s beaches.

The sieves at Associated Soil Engineering were used to compare the size of sand granules taken from Seal Beach against those collected from various points along the Santa Ana River.

The Santa Ana River grains, testers found, ranged from 0.4 to 0.5 millimeters in diameter, just slightly larger than the 0.2- to 0.4-millimeter size of the ones taken from Seal Beach. That’s nearly a perfect match, according to Russell Boudreau, a soil consultant for the city.

“It looks pretty good,” he said. The Santa Ana River sand “is a bit coarser than what’s out there already, and that’s a good situation.”

The match has set the stage for what may be the city’s first realistic solution to an age-old problem. By transporting 150,000 cubic yards--about 9,000 truckloads--of river sand to the beach, officials say, they can begin to replenish the strand that for many years has been slowly eroded by the surf.

“The city is always looking for sand,” said Lee Whittenberg, director of development services. “We have an identified need to place sand on the beach.”

That wasn’t always the case. Historically, according to Whittenberg, sand carried away by the surf during winter was annually replenished by the silt washed down by the San Gabriel River during summer.

But in the 1940s, engineers began building a series of jetties and dams to shut off the river at Anaheim Bay. As a result, he said, “we just don’t get much sand coming naturally onto the beach anymore.”

The problem became especially apparent during the winter of 1983 when the damage from a series of violent storms made it clear how much erosion had taken place. Since that time, the beach has been so narrow that storm-driven surf laps at beachfront homes.

Since then, Whittenberg said, Seal Beach has lost an estimated 5,000 to 6,000 cubic yards of sand a year, and “the beach just keeps getting narrower,” he said.

Engineering consultants estimate that it would take about 240,000 cubic yards of imported sand to restore the beach to the point where nearby property could be adequately protected.

The Santa Ana River sand “won’t solve our problem, but it will go a long way,” Whittenberg said.

While the city has, from time to time, imported small amounts of sand, Whittenberg said, it has usually been discouraged from doing so by the incompatibility of available sand--imported grains should be slightly coarser than the native stuff to avoid being quickly washed or blown away--and the prohibitive cost of such ventures.

Those obstacles themselves, however, were overcome by a contractor’s recent proposal to haul away tons of sand slated to be removed by the Santa Ana Flood Protection Agency and deliver it to Seal Beach.

Because the contractor is being partially paid by the agency, Whittenberg said, he offered to deliver the sand at a cost to Seal Beach of about $500,000--a fraction of the $2.5 million previous bidders have demanded for the same amount of sand.

The Seal Beach City Council, which is accepting bids from contractors to spread the imported sand on the beach, discussed the matter at a council meeting last month. The California Coastal Commission also has approved the project. And assuming approval by the Army Corps of Engineers, Whittenberg said, a fleet of trucks may begin hauling the stuff to the beach early this month, with delivery completed in about 25 days.

Soil engineers estimate that the new sand would add about 60 feet to the beach, a prospect welcomed by most residents.

“I’ve watched the sand go over 20 years,” said Robert Bullard, a 38-year-old surfer who rents a house on the beach. “It causes overcrowding; there’s not enough room for everyone to lie on the beach.”

“I want them to get more sand,” Dana Casazza, 25, said during a late-afternoon stroll along the concrete walkway bordering the beach. “I like the idea; the way the waves crash here doesn’t seem level.”

Not everybody, however, is opposed to the effects of the fleeting sand. Ron Derr, 42, said he likes the shoals it creates just off the beach. “The halibut like to stay on top of the shoals,” he said. “It makes the fishing better.”