Excavation throughout the whole length of the canal is being carried on as much as possible in the dry as this has been found to be the cheaper method.

Upon the Atlantic Division, during the fiscal year 1908–’09, a dredging fleet consisting of one sea-going suction dredge, two 5-yard dipper dredges and three French ladder dredges worked on the section between Mindi and deep water, removing 6,039,934 cubic yards, of which 427,005 cubic yards were rock. The rock is removed by blasting. Holes averaging 15 feet apart are drilled to a depth of 50 feet below sea level, loaded with dynamite and fired. At the close of the year nearly 3 miles of the channel from deep water were completed.

The plans for breakwaters in Limon Bay were recently changed. Originally breakwaters were planned to extend nearly parallel to the axis of the channel to protect against filling by wave action. However, it was found that the northers entering between these breakwaters would lack room to dissipate and so vessels would be unprotected for a great portion of the distance to the locks. Accordingly two breakwaters have been planned which are to be so placed as not only to prevent filling but also to give shelter to shipping.

On the Culebra section of the Central Division considerable trouble has been caused by the great rainfall. To carry the rain off quickly diversion channels have been constructed at a large expense of money and labor.

Water falling in the prism is cared for by the cut itself. In the process of deepening pilot cuts are started from either end towards the summit which is now between Empire and Culebra. Drainage in either direction is by gravity through these cuts.

The total amount excavated from the canal prism in this division during the past year was 18,442,624 cubic yards, 12,291,472 cubic yards being rock. At the close of the year 43,574,954 cubic yards remained to be removed. The material is loaded on the cars by steam shovels, is hauled to the various dumps, and unloaded by a huge plow-like apparatus which is drawn from end to end of the train. Part of the spoil aided in the rebuilding of the Panama Railroad; the rock from Empire and Bas Obispo went to Gatun for the dam, and some material was hauled to Balboa on the Pacific and was there used in reclaiming ground and in building a breakwater in Panama Bay to cut off silt-bearing currents which were filling up the excavated channel. It has been built out about 2 miles by dumping from a trestle built for the purpose. One mile more remains to be built.

The slides in Culebra Cut have continued. The largest, called the Cucaracho slide, measures 2,700 feet along the cut, involving an area of 27 acres. During the year 1908–’09, 670,017 cubic yards were removed from this slide but it is estimated that 700,000 more are still in motion. Drainage seems to be ineffectual in these cases.

The original summit at Culebra Cut was 333 feet above the sea; it was lowered by the French to 157 feet and the lowest point at the summit is now 143 feet above sea level.

The lake section of the Central Division extends from Gamboa to Gatun. The Chagres River here crosses the line of the canal 23 times, forming a series of peninsulas. A portion of the channel 2,700 feet long, 500 feet wide at the bottom and 50 feet deep, was completed May 25, 1909 and the waters of the Chagres turned in. A total of 1,784,459 cubic yards were taken out, of which 1,350,308 were removed in 1908–’09. From the remainder of this division 2,625,283 cubic yards were excavated in 1908–’09.

To secure the necessary width and depth between Pedro Miguel and Miraflores on the Pacific Division 1,279,600 cubic yards of material, of which 63,600 are rock, must be excavated. The material still to be taken out between Miraflores and deep water is 13,000,900 cubic yards of loam and 1,725,000 cubic yards of rock. It has been decided to remove all rock between the locks and for 2 miles below the Miraflores locks, in the dry. This will leave 3,600,000 cubic yards of loam and 123,000 of rock to be removed by dredging and blasting.

The dredging fleet in Panama Bay for 1908–’09 consisted of one sea-going suction dredge, one 20 inch suction and pipe-line dredge, one 5 yard dipper dredge, and four French ladder dredges. They removed 8,475,931 cubic yards of material during the year. The channel is completed for about 5 miles from deep water in the Pacific.

The entire present steam-shovel equipment on the Isthmus consists of forty-eight 95-ton, forty-two 70-ton, ten 45-ton, and one 38-ton steam-shovels, or a total of one hundred and one steam-shovels.

Dry excavation for the first quarter of the fiscal year 1908–’09, (July 1 to October 1), cost 63 cents per cubic yard for direct charges and 12 cents per cubic yard for general administration, making a total of 75 cents. Dredging cost 9 cents per cubic yard for direct charges and 2 cents per cubic yard for general administration. The average cost per cubic yard for excavation was 40 cents for direct charges and 8 cents for general administration, making a total of 48 cents.