Bulletin Volume 820-822 (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. Excerpt: ...there is little to choose between the two sites. The final decision depends mainly on cost and convenience of construction. From geologic considerations it would be best to eliminate all possible saddles, thus favoring site 5, but engineering considerations may outweigh this advantage. RESERVOIR LEAKAGE The possibility of leakage from the reservoir presents difficult and vital problems with respect to the ultimate success of the project. It is almost a foregone conclusion that rocks of the general type which exist in the area--that is, young sedimentary strata, largely calcareous--will be subject to leakage. It is necessary to determine as closely as possible the extent and effect of the leakage. The geologic and topographic situation of the reservoir sit--a structural and topographic basin, rimmed on all sides by high ridges of resistant and relatively impermeable rock and breached only by the Rio Chagres above Gamboa--makes it possible to predict with confidence that whatever water leaks out will eventually find its way into Gatun Lake, where it is desired. To this extent the disadvantage of leakage is minimized. One possibly serious disadvantage remains--namely, that leakage may increase in time to such an extent that it will produce a breach either in the dam foundation or 31 in some part of the ridges close to the dam, with consequent catastrophic results. The possibility of such a breach is the only thing that would seem sufficiently serious to warrant condemnation of the project, for in view of the need for the reservoir and the lack of other suitable locations, even considerable uncontrolled leakage into Gatun Lake would be preferable to no reservoir. It is believed that with proper precautions in construction a dam which will be safe from danger of brea...