Photo of the Week

THIS WEEK'S PHOTOS MAKE 1,000 WEEKS OF THE WEEKLY PHOTOS SINCE I STARTED THIS WEBSITE.

"By the end of the first week of September, 1913, the Canal excavation was essentially finished. All the railroad tracks and steam shovels have been removed in anticipation of flooding the entire Culebra Cut to Pedro Miguel Locks by opening the valves on the dike at Gamboa on October 1, 1913. From now on, the material will have to be dredged. Almost immediately, tremendous slides closed the channel. In the background, just beyond the larger pond, a slide from the west by Culebra and slide from the east, off the north side of Gold Hill, have met in the middle of the channel, effectively blocking it. The only way to remove the material from the slides would be to wait until the dredges could be floated into the area. In the meantime, rains started filling in the area between the slides at the north and south ends of Gold Hill. Many of the dredges were in the Pacific, and sufficient water to float them from Pedro Miguel Locks to the slides would have to come from Gatun Lake once the Culebra Cut was flooded. To fill the channel to Pedro Miguel, a channel through the slides would have to be cut by hand labor and dynamite". Photo and narration from Ron Armstrong's book, The Panama Canal - The Invisible Wonder of the World.

Above photo taken on September 13, 1913 shows the Cucaracha Slide on the right has filled in to the 65 ft. level, 25 ft. over the finished channel bottom. It later closed the channel completely.

The Cucaracha Slide has been a real nuisance for the Canal Diggers since it started sliding in 1907 and has continuously filled in the channel as soon as it was cleaned out.

" It had a total area 47 acres and extended up the east bank of the Canal for about 1900 ft. from the axis of the Canal. When it began its progress was disconcertingly rapid. Its base, foot , or "toe" - these anatomical terms in engineering are sometimes perplexing - moved across the canal bed at a rate of 14 ft. a day. All that stood in its path was buried, torn to pieces of carried along with the resistless glacier of mud. Not content with filling the Canal from side to the other, the dirt rose on the furthur side to a height of about 30 ft. Not only was the work of months obliterated, but work was laid out for years to come. Indeed in 1913 they were still digging at the Cucaracha Slide and the end was not in site. This slide was wholly a gravity slide, caused by a mass of earth slipping on the inclined surface of some smooth and slippery material like clay on which it rests." From Willis J. Abbot's book, Panama and the Canal - In Picture and Prose.

With no more track, dirt trains or steam shovels how were they going to clean this slide out so the water could pass and fill the rest of the cut to Pedro Miguel. Once there was water, dredges could be floated to the slide and start digging. Below was the plan of attack.

CUTTING THROUGH CUCARACHA SLIDE

After the blowing up of Gamboa dike, the southern end of the Canal, beyond Gold Hill, was separated from the waters of the lake by the foot of Cucaracha slide. Beginning October 6, 1913 forces of the Central Division had been engaged in digging a trench through the top of this barrier to allow the passage of the water from the north side. Successive downward movements of the slide, however, kept closing the trench, and it was decided to blow a gap in the barrier in the hope that the water would rush through it. A ton and a half of dynamite was placed in the toe, just opposite Contractor's Hill and exploded at 4.15 p. m., October 10, 1913. The explosion threw a great mass of earth and rock high into the air, and stones were hurled as far as 1,500 feet on either side, but the clay of the slide slumped back into place and closed the break before any considerable amount of water had passed through. Later blasts produced similar results, and the effort to clear the barrier in this manner was abandoned on Saturday, October 11. Trenching with pick and shovel was resumed that morning, and water began to pass through to the south side of the slide at 3:43in the afternoon. During Saturday night, a movement of the slide closed the trench. It was opened again by 11 a. m., Sunday, October 12. and has remained open since. A force of 200 men with shovels has been engaged in keeping the trench clear, and, with the assistance of the flowing water, making it deeper and wider. By 4 p. m., Sunday, pipe connections had been made with a water tank on the south side of Contractor's Hill and the work of the men with shovels was augmented by sluicing with a 3-inch hose along the lower side of the barrier. During the forenoon of Monday, October 13, a 2-cylinder air-driven pump and connecting pipe and 4-inch hose were brought from Empire and installed on the north side of the slide. At 2.50 p. m., this outfit began supplying water at 150 pounds pressure for sluicing the northern, or upper, part of the trench. This so facilitated the work that by 4 p. m., the water was flowing over the slide at the rate of about 40 cubic feet a second, in a stream from six to eight feet wide and approximately a foot deep, moving about six feet a second. It is believed that this method will so increase the flow as to fill the south end of the Cut within a convenient period, though all calculations may be upset by further movements of the slide. The material of the slide is a dense, adhesive clay, intermixed with stones up to two feet in diameter, and does not yield easily to the flow of water.
     The trench through the slide is parallel to the axis of the Canal and about 20 feet from the west bank. Its intake is at elevation 66.5 feet above sea level, and its discharge at the level of water in the southern part of the Cut, which was at elevation plus 43.4 early in the evening of October 15. The trench is in two sections, with a total length of 600 feet, separated by a small lagoon, about 300 feet across, enclosed between elevations of the toe of the slide. The material now in the Cut from the slide amounts to about 600,000 cubic yards.
     The trench through Cucaracha slide has been deepened about a foot and a half, and widened slightly, since beginning of sluicing at the upper end, on Monday afternoon, but the flow of water has increased only slightly. The surface of the water in the south end of the Cut was at 43.1 feet above sea level at 8 o'clock in the morning of October 15, giving about a 4-foot depth in that part of the Canal. On October 14, it stood at +42.85. On the north side of the slide the surface of the water was at 68.96 feet above sea level on October 15, at 10.30 a. m.
      By evening of October 15 the flow had increased to 60 cubic feet per second, and it is believed that by Tuesday, October 21, the water south of slide will be of sufficient depth to float a dredge.
      The last Culebra slide, immediately north of Gold Hill, made a movement across the channel on Saturday and Sunday, but sufficient clearance remains to allow passage of dredging vessels. The material at the foot of this slide is mostly rock, and it is possible that ladder and dipper dredges will be brought from the Atlantic entrance to work on it.
      Surveyors from the Sixth Division are engaged in placing water-gage rods and range markers, showing center line of Canal channel and liners 150 feet each side of center, in preparation for beginning of dredging. Final adjustments are being made at the twin pump relay station south of Contractor's Hill, and at the electric transformer station, for supplying it with power, diagonally across from it, on the 95-foot berm along the east bank. Discharge pipe and pontoons for supporting it on the water, have been distributed along the west side for a distance of about 1,000 feet, between the relay station and the foot of Cucaracha slide.

Canal Record Volume VII October 15, 1913