| The Bucyrus Company delivered its dredge to the BPC in June 1916. The machine was a special type of ladder dredge that required very low headroom and had a floating hull that required only about 2' of water. The dredge consisted of continuously operated ladder buckets and a belt conveyor that placed excavated materials on the riverbank. The machine was modified to run on electric power because the BPC was concerned that steam power might damage nearby trees and shrubbery with its smoke and heat. The dredge was not put into use immediately, however, because a special hull had to be built and a dredge operator hired. The wrong engine was delivered with the dredge, further delaying the excavation process. In the meantime, Niles, Downer, and Clarke visited Bridgeport, Connecticut, to observe another Bucyrus machine in operation. The machine excavated from one side and deposited material up to 90' away on the other. The BPC observers concluded that this machine would be efficient for excavating river channels and small lakes, as well as general grading and excavation work within the BRPR.(178) The 1917 construction season provided an opportunity for the BPC and the Bucyrus Company to test whether the excavator could meet contract requirements. The machine would be purchased only if it met the BPC’s expectations. The dredge passed a test in Bronxville, working in the area from Pondfield Road to a point south of Palmer Road where the river was thickly fringed with trees. Problems surfaced when the excavator encountered sunken logs and rocks that hindered its operation. The lower tumbler on the bucket ladder was redesigned and this modification proved satisfactory when the next set of tests began in September. Submerged logs and boulders again posed problems and caused significant delays, primarily because the bucket chains kept breaking. Downer recommended that a stronger chain be used. The section under the railroad bridge at Woodlawn proved particularly problematic due to the presence of old wooden piles in the river bottom. Crews had to cut off 156 piles to ease the dredge’s passage in this area. Near East 234th Street, the river bottom was composed of soft, saturated soil and the excavator had to be set upon heavy timber platforms to keep it from sinking. Downer reported that the average daily excavation over the twelve-day test period was only 53.7 cubic yards of material, which was substantially less than anticipated. The machine’s performance, however, was deemed satisfactory and the BPC agreed that the dredge met the contract requirements. Downer explained that the Bucyrus Company had been instructed to design a machine that would dredge a riverbed of silt and mud, which was expected to be easy work. The company should not be penalized for the fact that the riverbed was full of sunken logs and "nests of boulders." Downer praised the Bucyrus Company for spending a great deal of time and money in testing, rebuilding, and strengthening the machine to give a better performance than was originally specified in the contract. He concluded that the company had completed the contract in good faith and recommended that the BPC accept the excavator. In judging the effectiveness of the Bucyrus machine, Downer figured that it would enable BPC forced to accomplish the river excavation component of the project at less than half the cost contractors would charge for the job. The BPC could dredge at a cost of about $.17 per cubic yard of material, including machine depreciation. The lowest bid offered by the contractors was $.594 per cubic yard.(179) In addition to the specially built Bucyrus dredge, Downer recommended the BPC purchase a Monighan dragline excavator. This machine had a walking device and loaded material into wagons pulled by muleteams.(180) |
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| (178)Bronx
Parkway Commission, Report, 1917, 48; Bronx Parkway Commission,
Minutes, June 27, 1916, 324-327; May 26, 1917, 268-70; July 25, 1916,
349-58; October 24, 1916, 445-448. |
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