Along the SUSQUEHANNA RIVER, on which is CONOWINGO DAM(power station open daily 9 a.m. -4 p.m.), are high ridges with steep wooded bluffs bordering a flat river valley that is a mile wide; the river in low water flows over a shallow rocky bed, and in flood swells broadly and rushes with great force. Conowingo Lake, extending 14.5 miles up the river, has lessened the ruggedness of the banks, but on the whole has greatly enhanced the scenic beauty. Downstream from the dam the river retains its natural aspect.US 1 crosses the Susquehanna River on the crest of the dam,which is provided with spillways under the roadbed. Before the building of the dam in 1928, the highway crossed on the old Conowingo Bridge, two miles N. The Conowingo power plant was built by the Philadelphia Electric Co., and completed in 1928. It has seven units of 54,000 horsepower each, with provision for ultimate installation of four additional units. The transmission lines carry the current at220,000 volts, delivering at Philadelphia each year many million kilowatt hours. The dam is 4,648 ft. long and is based on solid rockat a depth of 96.5 ft. The turbines are spaced along the dam, the large power station being at the western end. The Susquehanna River, though one of the long rivers in easternUnited States, winding 420 miles, has rapids and shoals in its lower course, so that it is navigable for only about five miles from its mouthin Chesapeake Bay.