77//'; ir,^.S7//.VG'7Y).V AQIICIHUT .Ul 



city arc already overUxed in sujmlying the present rate of con- 

 sumption, and no relief will be felt by consunu-rs until some 

 method is i)rovided for ])ringing an increased (luantity of water 

 from the distributing reservoir into the city. 



General Meigs was in charge of the work upon the \Vashin>;i.)U 

 aqueduct from the time of the first survey until -Inly, ISOO, when 

 he was relieved by Captain H. W. Benham, of the U. .S. Corps <)f 

 Engineers, who in turn was succeeded by I.ieutenant James St. C, 

 Morton, of the same corps. On February 22, 1861, after an ab- 

 sence of seven months, General Meigs was again placed in charge, 

 and tiie work was practically completed by him. In June, 1802, 

 owing to the overworked condition of the W'ai- Department, the 

 charge of the Washington aqueduct was transferred from that 

 department to the Department of tiie Interior, where it remained 

 until April, 1867, when it again passed int<^ the care ol'the War 

 Department, and has remained there ever since. 



In his report U[)on the i)roi)osed line of the conduit, CJcneral 

 Meigs states that seven miles after leaving Great Falls the only 

 serious obstacle in its whole course, the valley of Cabin Jolni 

 branch, is encountered. This valley, he says, might be crossed 

 by pii)es, but he states that in his i)roject he has avoided them 

 because '" they always (K^casion a loss of head or else exceed in 

 cost the bridges they reidace." He therefore first proposed to 

 cross the valley by a bridge 482 feet long and 20 feet wide, sup- 

 ported upon six semi-circular arches of 60 feet span, resting U[)on 

 piers seven feet thick at the top and of various heights, the highest 

 being .52.> feet. The estimated cost of this bridge was 872.4(»0. 

 This plan was afterward entirely changed and the present mag- 

 nificent structure, the grandest stone arch in existence, was 

 erected. 



The total length of the bridge, including al)Utnients. is 450 

 feet ; its width is 20 feet 4 inches, and its height above the bottom 

 of the creek 1(X) feet. The sjjan of the arch is 220 fei't and the 

 rise /)7.26 feet. It was begun in 1857 and (uunpleted, with the 

 exception of the parapet walls, in 1864. These walls were bnilt 

 in 1872-73, vehicles having l)een prevented from getting ofV the 

 bridge prior to that time by timber guards. .All the original 

 plans of the bridge arc signed by General Meigs as chief engineer 

 of the Washington aqueduct and by Alfred L. Hives, a.>*sistant en- 

 gineer, Cabin .lohn division. The entire bridge contains lo,28.*i 

 cubic yards of .stone masonry, concrete, and l)rick-w(»rk, and it 

 cost, complete, al)OUt S2o4,<)(n The cnt-st..nc arch is of t^iincy 



