From the Forest to Your Faucet : Environment: Following a water drop through the San Gabriel Basin reveals the complexity of cleansing the polluted water table.

Far from suburbia’s lush lawns, swimming pools and golf courses, Kevin Sweeney nudges his small motorboat into a steep-walled cove where braids of a waterfall cascade over a rocky ledge.

Sweeney, the dam tender in charge of Cogswell Reservoir and Dam, could not travel by boat to this spot in the San Gabriel Mountains when the drought was at its most severe two years ago. He had to walk an hour upstream from the reservoir and follow the winding, dusty banks of the San Gabriel River’s West Fork, which was then a trickle.

Now, speaking above the rushing waters, Sweeney, 41, says: “Had we come here two months ago we couldn’t have heard each other talking because the water was such a roar.”

The San Gabriel Mountains, as much as any other place in California, testify to the drought’s end. Since October, more than 77 inches of rain has fallen in the mountain forest--the most in a decade. That’s twice the annual average rainfall for drizzly Seattle.

As the bountiful runoff percolates into the showers of South Pasadena and the carwashes of Covina, the juxtaposition of rain-swollen mountain reservoirs with the semi-desert of the San Gabriel Valley serves as a reminder of the value of relying on local water sources, instead of piping in water from afar.

The story of Southern California’s reliance on water from Northern California and the Colorado River has grown to mythic proportions, most prominently in the film “Chinatown.”

Yet, since the 19th Century, the San Gabriel Valley has nourished its orange groves, fostered its subdivisions and factories, and watered its golf courses by depending largely on mountain runoff to fuel vast aquifers spreading below ground from Pasadena to Pomona.

In amazing feats of chutzpah and engineering during the past 200 years, a diverse group of water consumers and managers--Indians and the early mission padres, laborers from Mexico, China and Japan, farmers, dam builders and hydrologists--each in their turn harnessed the rain and snow flowing from the mountains via the streams and arroyos.

Concrete channels, earthen and rock reservoirs, rivers of steel pipe, rock and concrete dams and stone-lined spreading basins now shepherd every drop to supply the water needs of 1.7 million residents of the San Gabriel Valley and its businesses and industries.

Nature blessed the valley with highly porous soil and easy access to water, which made it an ideal place for orchards requiring good drainage. But with the blessing came a curse.

Through the porous soil, nitrates from fertilizers and wastes from livestock tainted the water table. And the aquifers were sullied by septic systems of the subdivisions of people lured here by stories of sunshine, palm trees and fragrant orange blossoms.

Likewise, chemicals became a part of everyday life beginning with World War II, and soon solvents and gasoline from leaky storage tanks began making their way into the water table. Today, the San Gabriel Valley’s water supply faces one of the nation’s worst underground pollution problems.

Following a drop in a reservoir to a family’s faucet illuminates how monumental the cleanup task is. To understand the circuitous, sometimes perilous journey water makes for 25 to 30 miles from the Angeles National Forest into the valley, imagine one drop following one path.

First, the drop falls into the cove where Kevin Sweeney’s boat slices dark-blue waters, surrounded by hillsides with blue heron, Indian paintbrush wildflowers and Nelson bighorn sheep.

Daily, drops and drops of runoff fill the San Gabriel Basin, stretching from Alhambra to La Verne and supplying 90% of the water needs for the 1 million residents who live in that part of the valley. And mountain runoff replenishes other, smaller aquifers serving part of the needs of Pasadena and Pomona and their neighboring communities.

The drop moves through Cogswell Reservoir, the first of three reservoirs that capture 210 square miles of mountain watershed. The reservoirs are the tip of the iceberg of a vast water delivery system.

Then the drop goes over the 260-foot-high Cogswell Dam, its concrete spillway overflowing into the wild trout fishery of the West Fork, lined with boulders as big as cars and leafy sycamores, alders and oaks.

Descending from the West Fork, where on Sundays Latino church groups baptize their faithful, the drop passes onto the next reservoir and dam, called San Gabriel.

The drop skirts a pipeline whose history dates from more than 100 years ago when arguments over who owned the water were marked by the loud reports from dynamite and rifles.

The pipe diverts water controlled by the San Gabriel River Water Committee, also known as the Committee of Nine. The group represents just a part of the patchwork quilt of 55 public and private water companies, more than 100 water-rights holders and a host of local water agencies that today have a say in who owns the water, how much it will cost and where and even the timing of when every drop makes its journey.

From San Gabriel, the drop is guided to Morris Reservoir and Dam. Propelled by gravity and water pressure, the drop bursts into an open, rocky berth of cascading blue-green waters.

As the drop falls into the mouth of San Gabriel Canyon, it encounters a special feature benefiting the region’s water supply: river-bottom land fashioned by crumbling mountains.

Over the millennia, especially around Azusa and Irwindale, where today many rock and gravel companies have dug out their homes, residue the river brings down from the mountains has formed a porous under-layer and surface for the San Gabriel Valley. This alluvial fan, as it is known, is created by the San Gabriel River and by the geologically youthful San Gabriel Mountains--which continue to grow, thrust upward and slough off rock and soil.

Instead of rushing downstream, about half of the runoff is directed out of the river and into above-ground holding basins called spreading grounds or spreading basins. These allow the water to quickly percolate into the underground water table. The rest is diverted into other spreading grounds along the San Gabriel River or flows to the ocean.

Some of these spreading grounds stretch across areas the size of football fields. Linked side by side, they are divided by berms of river rock worn smooth as eggshells.

By the intersection of the Foothill (210) Freeway and the San Gabriel River (605) Freeway, the Santa Fe Dam spreading basins cover up to 168 wetted acres, looking like connected fishing ponds.

To the south, in a nine-story office building in Alhambra, water engineers with the Los Angeles County Department of Public Works keep track of how much water is supposed to flow into the spreading basins, based on water rights and conservation needs.

Besides recording how much water passes through the mountain reservoirs and dams, the engineers monitor rainfall gauges visually and via radio-controlled devices. With a roomful of computers that help to track the water flows during drought and flood times as well, the county hydrologists decide how much water to hold in the reservoirs and how much to divert to spreading grounds.

At the Santa Fe Dam spreading basins the drop penetrates into the porous ground. Some 100 to 150 feet below the surface it finds the water table--the topmost part of an underground reservoir, which permeates layers of rock and sand, thousands of feet deep in some places.

The rains, including those from as recent as last weekend’s unusual storm, have tremendously boosted the water table.

Weekly, the levels are checked so water officials can ensure the efficient operations of the region’s 300 private and public water wells. On one of his regular checks, water engineer Kevin Smead confirms the rising water table as he measures what is known as the key well.

The most significant well in the San Gabriel Basin is located in an otherwise vacant lot in Baldwin Park and covered by a scruffy metal cover painted green. In 1991, so much water had been pumped from the San Gabriel Basin and the water level had dropped so low that the key well, the well used to measure the region’s water table, had to be drilled 80 feet deeper.

Smead, after lowering a 300-foot-long measuring tape with a battery-operated sounding device that beeps when it hits the water, announces: “It’s very good news, very good news.”

The water level is continuing to rise, nearly one foot since the last measurement, he says, reeling up the device. One foot represents an additional 8,000 acre-feet of water in the basin, or enough water to supply the needs of 16,000 households.

In the last two years the level has risen by 75 feet across the underground expanse from Alhambra to La Verne. That translates into billions of gallons of additional water for the San Gabriel Basin, whose capacity equals that of 500 average-sized reservoirs.

Having its own back-yard water supply means the San Gabriel Valley can quench its thirst cheaply even in times of drought, avoiding the expense of importing large amounts of water from hundreds of miles away.

Still, drought and “over-drafting”--taking out more water from the underground basin than the rains put in--make it necessary to import water from Northern California and the Colorado River and pipe it into the spreading basins.

In recent years, as the population has increased, the demand for the underground water has grown. And so has the debate between water officials, who say they can adequately manage the supply, and environmentalists, who say over-drafting is an unwise practice that has become too common throughout the state.

But an even more critical issue revolves around water quality and the extensive pollution of the San Gabriel Basin.

As the drop percolates through the rocky water table in Irwindale, it can become polluted with contaminants known as volatile organic chemicals, tainting the drop to a level as much as 100 times beyond the federal and state standards for safe drinking water. The same porousness that allows water to pool under the ground also allowed toxic chemicals to permeate the water supply.

The contamination was discovered in 1979, hardly a mile or so from the key well. A toxic cocktail of chemicals, including potentially cancer-causing ones, was found in wells near aerospace and defense industry contractor Aerojet, located on the Azusa-Irwindale border.

That discovery prompted testing of other wells, and five years later the federal government declared that the 180-square mile San Gabriel Basin was a Superfund site, placing it on a list of the nation’s 1,200 major environmental cleanups.

A variety of businesses--from farms to dry cleaners to gas stations to aerospace industries and machine shops--had apparently contributed to the drop-by-drop sullying of the aquifer.

This forced the closure of 100 of the region’s 400 wells. Ironically, the intricate nature of the underground geology allows huge pockets of polluted water to flow side-by-side with pockets of crystal pure water, separated only by a rocky layer.

Slowly, the pollution moves from place to place in the porous aquifer. A well can be horribly contaminated for years but then one day suddenly meet all drinking water standards.

Since the early 1980s, local, regional, state and federal water and environmental officials, along with political, business and community leaders, have grappled with how to resolve pollution. The suggested remedies and the cost estimates have varied greatly, ranging from several hundred million dollars to even $1 billion.

The most recent proposal came last month with the announcement of a $47-million plan by the Environmental Protection Agency to attack the filthiest sites in the basin, located around Azusa, Baldwin Park and Irwindale.

Already, some relatively small cleanup projects have been undertaken, including several with wells operated by the Valley County Water District, which serves customers in Baldwin Park, Azusa, Irwindale and West Covina.

After the drop’s slow migration underground through pockets of pollution, it makes its way to a Valley County well. Any given drop, hydrologists speculate, moves an average of one-tenth of a mile underground in a year. In rainy times, a drop moves much faster.

One block south of the Santa Fe Dam, on the border of Irwindale and Baldwin Park, a 600-foot-deep well pushes up the drop into a pipe that carries it above ground into a 32-foot-tall gray tank, filled with a thick layer of granular carbon--just like the material in fish aquariums. The drop filters through the carbon, which draws out pollutants.

After being treated with a minuscule amount of chlorine to counteract bacteria that might have grown in the carbon filter, the drop is piped into a 1.5-million-gallon water storage tank. Then it is sent into the water supply lines for residential and commercial customers.

Eventually, the drop flows out of a kitchen tap, just a few blocks away on Wimmer Avenue, in a working-class neighborhood of small stucco houses in Baldwin Park, where it helps to wash the dinner dishes of the 10-member Ramirez family.

Frank and Tina Ramirez have two stoves and two sinks in their kitchen and no automatic dishwasher. “I don’t need one. It wastes water. Anyway, I have all these wonderful dishwashers,” Tina Ramirez says, looking around a houseful of family members, including three assigned for the day’s dishwashing.

After going down the drain, the drop enters the sewage system on a seven-mile journey to Whittier Narrows.

Finally, at a reclaimed water plant of the Sanitation Districts of Los Angeles County, the drop is subjected to a three-stage sewage treatment process in a series of tanks by the San Gabriel River Freeway and the Pomona (60) Freeway.

About 75 million to 80 million gallons a day of water are reclaimed to a standard that makes the water safe enough to drink, the facility’s officials say.

But state health department regulations allow the water to be used only for purposes other than drinking.

Fourteen hours after the drop enters the plant, it leaves, headed into a short pipeline to the California Country Club next door, where the drop is piped into a small pond with mallards skittering across the surface.

Before sunrise, even before the earliest golfers arrive, a pump draws the drop from the pond. It then is sprayed from a sprinkler system onto the nearby 10th green.

A few hours later, a foursome putts on the 10th green, bordered by a pond filled with reclaimed water that feeds the sprinklers. Now the drop is evaporating into the air to eventually join a cloud.

In time, it then will make its way back to create more rain that eventually will fall high in the San Gabriel Mountains.

The Journey of a Drop of Water

The 1.7 million residents who live in the San Gabriel Valley rely mainly on drinking water that comes from rainfall and runoff that seeps into vast aquifers. In the wettest of times--such as last winter--this underground source can supply 90% of the area’s needs. The Pasadena, Pomona and neighboring areas, however, depend more heavily on water imported by pipeline from Northern California and the Colorado River. But for much of the local water supply, the journey of a drop of water begins in the San Gabriel Mountains.

1. A drop of rain falls into steep, isolated canyons and makes its way into the San Gabriel River, along with other runoff that gathers there--sometimes quickly and sometimes slowly.

2. The drop passes through a series of three major reservoirs and dams--Cogswell, San Gabriel and Morris, which collect the runoff from more than 210 square miles of the Angeles National Forest.

3. Descending into the San Gabriel Valley, the drop is shunted into “spreading basins,” areas as big as football fields that allow the runoff to quickly percolate underground. Many of these are located around the junction of the San Gabriel River Freeway (605) and the Foothill Freeway (210).

4. Wells, drilled as deep as 600 feet below the surface, pump up the drop.

5. On its journey through the basin, the drop is polluted by solvents and degreasing agents that have seeped into the underground water supply over the last half century. In May federal environmental officials announced plans to build $47 million in treatment facilities to attack the filthiest water sites, located in Azusa, Baldwin Park and Irwindale.

6. As part of earlier cleanup efforts, several treatment facilities have been built. The polluted drop passes through tanks with layers of carbon particles that filter out chemical contaminants. Before the water is sent into the water supply lines, chlorine is added to counteract bacteria that might grow in the carbon.

7. After the drop comes out of a kitchen tap or shower, it goes down the drain. The waste water is carried south to Whittier Narrows where it is treated at the reclaimed water plant run by the Sanitation Districts of Los Angeles County. Seventy-five million to 80 million gallons of sewage are “cleaned” daily at the plant along San Jose Creek. Half of that is actually recycled to customers such as golf courses.

8. The drop is piped to the California Country Club and is sprayed onto a green. Some of the drop’s moisture evaporates, and the cycle eventually begins again. Sources: San Gabriel Basin Water Quality Authority, Main San Gabriel Basin Watermaster, Los Angeles County Department of Public Works and Valley County Water District, and the Sanitation Districts of Los Angeles County.