Page:Tioga Road (HAER No. CA-149) written historical and descriptive data.pdf/16

 operations and prevent the burning of debris. The park engineer's report recorded the special care taken in blasting the exposed granite:
 * Close check was made of the contractor's blasting operation. Blasting diagrams were made and powder poundage watched in order to avoid as much scattering of the rock as possible. Holes were spaced a 4.6 foot centers and it was insisted that the holes be loaded [with dynamite] at the bottom in order to avoid scattering which would have resulted from I muzzle-loading.' This procedure resulted in the rock breaking out pulverized in the bottom of the cuts and in large blocks at the top. It was these blocks which gave a smothering effect to the blasting operations and in general scattering of the rock was avoided.85

The large blocks of rock were in many cases salvaged for the construction of bridge abutments and buildings.86

By the time work resumed in the summer of 1935, Morrison-Knudsen had fallen further behind on the segment between Crane Flat and McSwain Meadow, and increased their work force to 240 men in an effort to make up time. By the end of September, the company had opened up nine miles and fully cleared a seven-mile stretch. All the clearing work was not complete until November, however, and the pioneer road through the section was just under construction.87

The Bureau of Public Roads awarded the contract for surfacing the Tioga Pass-Cathedral Creek section to Peninsula Paving Company of San Francisco on 25 July 1935. The company began work in September, using the existing construction camp at Budd Creek. A crusher plant was installed here, and went into service on 11 September. More delays set in, an the project engineer claimed the company mismanaged its inexperienced crew. The project had been scheduled for completion in the 1936 season, but the deadline was not met. The section was subsurfaced in the 1937 season with a seal coat and a 3" layer of granite screenings. At the Tioga Pass entrance station, the road was widened to 30' to accommodate a new checking kiosk. The paving work was finally completed and accepted by the Park Service on 22 September 1937.88

On the western part of the road, Morrison-Knudsen began work on the bridge which would carry the Crane Flat-McSwain Meadows section over the South Fork of the Tuolumne River in June 1937, excavating footings and quarrying stone for the abutments. By the end of July, the north abutment had been built, and by summer's end the other abutment was 90 percent complete. The steel beams were placed in September, and the concrete deck and curbs were poured. The bridge [HAER No. CA-108] was completed in October.89

By this time, the National Park Service had rejected the proposed "High Line" route through the Mount Hoffman-Ten Lakes-Tuolumne Canyon area, and completed work on a survey for the 21 mile section between McSwain Meadows and Cathedral Creek. The NPS proposed to let the contract the next year.90 This route would follow a higher course across much exposed granite and take the road along the northern shore of Tenaya Lake. Despite the initial plans, this section was not built until the late 19505, and at that time.

Throughout this period, the road reconstruction project was closely monitored by the Yosemite National Park Board of Expert Advisors, which wanted to prevent any significant disturbances to the park landscape. The Board of Advisors strongly objected to the proposed "high-line' route, writing that "The proposal to route the road north of Polly Dome is, in our opinion, a