The gold and silver industry began to decline in the 1950s, leaving behind hundreds of abandoned mines that have contributed to acid mine drainage problems. Rail traffic along the San Juan River declined with the closure of mines, although it was revived briefly in the 1960s by a temporary rise in oil production. When Navajo Dam was built along the upper San Juan River it flooded the towns of Rosa and Arboles as well as a large portion of the D&RGW San Juan Line through the river canyon. The federal government paid for the cost of relocating the line, which began operating in August 1962; however, this section along the San Juan River was abandoned barely five years later due to falling traffic. (The section of the San Juan Line east of Chama has been preserved as the Cumbres and Toltec Scenic Railroad, and the section from Durango to Silverton as the Durango and Silverton Narrow Gauge Railroad.)