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however, lost their lives when Irapped by the rising waters of Sespe Creek in Ventura County, and four other drownings were reported elsewhere in the region. Transportation was snarled as Iloodwaters in Cajon Canyon cut the main east-west lines of the Southern Pacific and Santa Fe Railroads, and more than 100 Los Anaeles streets were blocked by felled trees. The b . greatest monetary damage occurred in the Glendora-Azusa foothill area of the San Gabriel Mountains. A brush tIre in August 1968 had burned off erosion.retarding vegetation in the canyon area above the town of Glendora. The 4 days of rain on the bare soil were climaxed by a local precipitation burst of 2 inches in 3 hours. which brought down a torrent of sediment- and debris-laden water. Streets were boulder-strewn and sediment spread over streets and lawns and into homes (fig. 2). In places the streets were covered with sediment to depths of as much as 4 feet. Damage in Glendora was estimated at $2 million. It was with a feeling of relief, therefore, that southern Californians viewed the rainiess skies of January 22. The relief was short-lived, however. The rains of the preceding 4 days had saturated the ground and had produced a condition favorable for heavy runotT from ensuing rains; the stage was set for the deluge that was to follow. The rains started again on January 23 as the second 4-day phase of the storm arrived. Not only were antecedent conditions favorable for Figure 2.-Result of mudflow in Glendora, January 22. Photograph courtesy of Los Ange]es Times. B6 heavy runoff, but the time distribution 0_ precipitation during this phase was conducive t~ hi g h peak discharges, because the heaviest precipitation came near the end of the storm when streams were already swollen. In Los Angeles County, flooding was confined primarily to the headwater tributaries of the principal streams-the San Gabriel and Los Angeles Rivers-and to the smaller canyon streams that are directly tributary to the ocean. The heavy runoff of the San Gabriel and Los A ngeles Rivers was stored in flood-control reservoirs and released at rates compatible with the capacity of downstream flood channels. In the mountain and foothill areas, however. the rapidly rising tributaries of those two rivers left their banks and created havoc. Bridges. roads, and streets were washed ont and homes were destroyed or damaged; thousands of persons were evacnated. The sediment and debris carried by the streams added to the misery. Debris flows occurred again at Glendora to add to the damage suffered in the earlier phase of the storm. Damage of a similar nature, but not as severe. occurred 111 HIghland Park, Sherman Oaks, Verdugo Hills, Brentwood, Bel-Air, Hollywood Hills. Encino, and G]endale. Landslides. more aptly termed mudslides, also created much damage in those towns and buried seven persons alive in their beds when the slides entered their homes. Topanga Creek, a small stream directly tributary to the ocean, swelled to the size of a river. Almost 1,000 persons in T opanga Canyon were isolated when homes and roads were destroyed by water and mudslides, and three persons were smothered when mud swept through their home. On the coastal plain. street flooding occurred in many towns such as Manhattan Beach, EI Segundo, and Long Beach. (See figures 3, 4, and 5.) East of Los Angeles County. in the Santa Ana River basin, major flooding was confined to the upper reaches of the river and its mountain tributaries. The rampaging waters of such creeks as Cucamonga, Deer, Day. and Cajon damaged or destroyed by erosion an aggregate of sevcral hundred miles of improved flood ChannelS. Roads and bridges were washed out and the main lines of the Southern Pacific and Santa Fe