’. . . No one is free...

’. . . No one is free from error.’

Up San Francisquito Canyon in the San Gabriel Mountains, about 15 miles north of Saugus, there’s a huge monolith sitting in the middle of a stream bed.

It looks as though it doesn’t belong there. It doesn’t.

The monolith--a block of solid concrete about 30 feet across--is about all that remains of St. Francis Dam, one of two major construction projects envisioned, designed and built by self-taught engineer William Mulholland, chief engineer for the City of Los Angeles from 1886 until late in 1928.

The first project--the 233-mile Los Angeles Aqueduct, which has brought water from the High Sierra to the Southland since 1913, making possible the growth of the city into a major metropolis--was unquestionably his greatest triumph.

The second project--the dam, completed in 1926 to reclaim and store excess runoff from the aqueduct’s Power Plant No. 1, about a mile upstream--was unquestionably his greatest failure.

About 2 1/2 minutes before midnight on March 12, 1928, the gracefully arched concrete dam suddenly collapsed, sending a wall of water 100 feet high crashing down the canyon.

Hurtling downstream at nearly 20 m.p.h., the water wall flattened but widened as it headed toward the sea, 60 miles to

the west, sweeping away everything--orchards and barns, bridges and automobiles, homes and people--in its path.

Warnings relayed by power plant officials saved many. A Ventura policeman headed upstream, siren wailing, to ring the firehouse bell in Fillmore. A courageous telephone operator stayed at her threatened post so she could help spread the alarm.

But in the end, as many as 450 lives were lost, more than 1,200 buildings were destroyed and close to 8,000 acres of farmland were scoured from the face of the Santa Clara Valley.

An investigation revealed that weaknesses in the rock foundations of the dam had caused it to fail.

A coroner’s jury concluded that what had been perceived as one of Mulholland’s greatest strengths--his practice of relying solely on his own judgment, often relying on calculations and specifications kept solely in his head--may have been his greatest weakness.

The jury said the construction of a great dam “should never be left to the sole judgment of one man, no matter how eminent . . . for no one is free from error.”

Mulholland, his aging face lined with grief, took the stand.

‘Fasten it unto me if there was any error of judgment--human judgment,” he said. “I am that human.”