52 



THE ASSTJAN RESERVOIR. 



The engineers of the Egyptian Government have realized for a long 

 time that it would be nece.ssar^- to ytore some of the Nile water l)efore 

 Upper Egypt could receive the benefits of perennial irrigation or a 

 large area of Lower Egypt be reclaimed. For ten years Ijefore work 

 was undertaken toward liuilding the reservoir preliminary surveys 

 were made and manv reservoir sites were discussed. Investio-ators 

 resorted to ancient history and brought forth all the known facts 

 regarding Lake Moeris, which occupied part of the Imsin now known 

 as the Fayum province. One American engineer, who had studied 

 this subject and made some surveys, held that the Wady Ryan was 

 formerly Lake Moeris. Whether or not this })e true does rot matter 

 at this time. To-day it is the only practicable i-eservoir site between 

 the Mediterranean and Assuan. (See PI. XIX.) 



Early in 1894. after considerable discussion as to how reservoir con- 

 struction should be carried on and what sites should be utilized, a 

 technical commission was appointed. This commission consisted of 

 Sir Benjamin Baker, an Englishman; Auguste Boule, a Frenchman, 

 and Giacomo Torricelli, an Italian. They left Cairo February 26, 

 and returned March 23, having examined all the sites in less than a 

 month. The Wady Ryan and a number of Nile valley reservoirs were 

 discussed, the majority of the commission linally agreeing upon the 

 Assuan site. 



The Nile, from the town of Assuan to the dam site, is broken into 

 many irregular channels. The bed and banks of the river are largely 

 composed of granite. The first cataract of the Nile begins where the 

 water first encounters the granite. Engineers agreed that the dam 

 should be Iniilt in this locality, but as to its exact line there was a 

 great deal of discussion. Mr. Willcocks recommended that it be of 

 irregular alignment, running from one island to another, where his 

 studies indicated that the granite was solid, thus atiording a good 

 foundation; but the dam as finally luiilt is straight, and crosses the 

 river where rapids first appear. It was originally planned to make 

 the dam 100 feet high, but when it was found that a dam of this 

 height would cause the submersion of the temples on the island of Philae 

 it was determined, in vieAV of the protests of those interested in the 

 preservation of these ruins, to reduce the height 30 feet, although it 

 is possilde that it may still be raised to 100 feet. This would give the 

 reservoir a storage capacity two or three times greater than it now 

 has, while the ratio between the cost of the work and the volume of 

 water impounded would be greatly reduced. (Pis. XX and XXI.) 



The dam is 70 feet high, 6,400 feet long, 23 feet wide on top, and 

 82 feet wide on the bottom at the deepest part. It contains approxi- 

 mately 1,000,000 cubic yards of masonry. The depth of water at the 



