Show BRIDGING THE COLUMBIA A great engineering feat in the far aap northwest the recent completion of the great cantilever cant alever bride over the columbia river a at 1 rock island wash marks mark the accomplishment of the greatest feat of railroad engineering in the west the columbia at Wa natchee where the big bridge is being built is between and 1000 yards in width and from 12 to feet deep at low water its channel according to the seattle herald aldis is 0 worn o rn deep below the general surface of the valley and though the annual june rise is 85 35 to 50 feet it never overflows after many surveys and measurements the company decided to build a bridge high en enough ou ah not to interfere with navigation rather than a drawbridge at a shallower point and support the same on piers at the point selected for crossing crossing a basaltic butte rises feet ab above ove the valley the butte drops down dow to the river in shelf like terraces and on ofie one of these shelves the western approach of the bridge rests on the opposite bank stands a similar butte feet above the water I 1 and through this butte a roadway has been can cut for the eastern approach two hundred and fifty feet from the east bank of the river is an island or rather a hug hue ge rock on which the only pier in in the river is built between the ro rock k and in d the west bank flows the main main s tream stream which is feet wide and feet deep the whole bridge is feet long not counting the minor approaches and is feet above low water ma mark r and 70 feet above extreme high water the first span reaches from the III bluff on the west side feet to a shelf above the water line the second or main span reaches feet above the main channel to the river it weighs tons and in the center is 75 feet from top io bottom of the structure the third span extends from the island to the east bank the entire bridge is built of steh steal and wrought iron |