Arizona republican., 1906-05-29
CONSTRUCTION
 AT ROOSEVELT
Recital of Present Con.
 ditiORS at Dam Site
Progress Made in Various Parts Of the Wsrk--PreparatiOns for Lay- ing Foundation.

Engineer Hill was interviewed yes terday concerning the progress of work at Roosevelt. Nearly every step that has been taken in the way of con- struction, preliminary and permanent has been noted as it occurred, but what was desired of MT. Hill was general resume of the situation as it is today, a statement of how far each branch Of the work has advanced and what IS now being done. The information was furnished and is herewith passed along to the readers of The Republican.
 The contractors are busy at the dam site constructing the coffer dams that are a necessary preliminary to the lay ing of the foundation of the permanent dam. There will be two cOffer dams, one above and a smaller one below. The upper coffer dam is completed and the piling is being driven for the lower cof- fer dam. These coffer dams are made by driving sheet piling across the stream to depth that will make a SC cure foothold, then dumping rock and other material behind the wooden structure, of sufficient weight to pro- tect it from the ordinary flow of the river, or any small flood.
 The piling of the upper Golfer dam projects thirteen feet above the water line at the two ends. though for a dis tance of eighty feet in the center 1t projects but two feet above the water line When the time comes for divert ing the water of the river through the sluicing tunnel, or. possibly, huming the excess, this eighty-fOOt space may be raised by planking up against the uprights in the dam, should that be necessary. For the present, however, no effort is being made to divert the stream The lower coffer dam is 25O feet down the stream from the upper one. The intervening space will event ually accommodate the foundation of the permanent dam, which will be 165 feet wide at bedrock, leaving still plenty of room above and below the permanent foundation for the conduct of operations.
 Assuming that the area between the two coffer dams was filled with noth- ing but mud, water and cObblestOnes, it is estimated that it could be eXca- vated in two or three days, to bedrock, by the hydraulic machinery that will be employed, when the psychological moment arrives. However, there is a large quantity of this area filled with bouIders of immense size, too large for hydraulic removal, and which will have to be blasted and removed with der ricks. At this time five monster der ricks are engaged in moving such of these rocks as are exposed on the banks or in approachable places, the power for the derricks being furnished by the government electric plantv and gener- ated by the water falling through the penstOck from the Power canal. As much of this rock as possible will be removed before the hydraulic excava- tion is undertaken. and, when all is in readiness, mud, water and rock will fly simultaneously and as fast as hydraulic and electrical machinery can move it. It is expected that the hydraulic ma chinery will be started about the first of July, for, unless there are uneXpect- ed floods to interfere with operations, everything should be in readiness by that time, and the normal flow of the river be diverted from the channel.
 To anticipate a little, it will be inter- esting at this point to refer to the plan