 A Lock Haven log boom , smaller than but otherwise similar to the Susquehanna Boom at Williamsport , was constructed in 1849 . Large <unk> of timbers weighted with tons of stone were arranged in the pool behind the Dunnstown Dam , named for a settlement on the shore opposite Lock Haven . The piers , about 150 feet ( 46 m ) from one another , stretched in a line from the dam to a point 3 miles ( 5 km ) upriver . <unk> by timbers <unk> together with iron <unk> and rings , the piers anchored an enclosure into which the river current forced floating logs . Workers called boom rats sorted the captured logs , branded like cattle , for delivery to sawmills and other owners . Lock Haven became the lumber center of Clinton County and the site of many businesses related to forest products . 
