Bouquet Canyons. The road reopened on November 15, 1919, completely paved except north of Lebec, including the grade at Grapevine, which was only oiled. After a bond issue was passed in July 1919, this portion was paved from September 1919 to May 1921; the dangerous detour during the paving included a 20 percent grade. The paving added about $1 million to the cost, for a total price of about $1.5 million (about $ in ), which was not paid off until 1965. Asphalt was added on top of the concrete for south from Swede's Cut in 1922, and in 1924 a number of blind curves were widened and straightened. Bypasses and the fate of the bypassed road In 1929 the state decided to build a new bypass of the central portion through Piru Canyon, and to upgrade the north portion over Tejon Pass and down the hill to Grapevine. This Ridge Route Alternate, or Ridge Alternate Highway, shortened the route by and increased the minimum curve radius from . This was done for the safety of the road, which had many accidents, and to increase the road's capacity. The old highway was to be relinquished to Los Angeles County and incorporated into the county road system. Construction began in 1930, and the road south of Tejon Pass opened on October 29, 1933; replacement of the Grapevine grade was completed in 1936. The three-lane road, with a center "suicide" passing lane, cost $3.5 million (about $ in ), paid for by the state gas tax. It was estimated that it would pay itself off in 2.5 years with the savings in time and gas. A new bypass of the Newhall Tunnel, through Weldon Canyon, had opened on May 28, 1930, giving drivers a better route all the way from Los Angeles to Bakersfield. The roadway was widened to an expressway by 1952 at a cost of $13.5 million (about $ in ), with two lanes in each direction and a center median, but still with at-grade intersections. Even this four-lane Ridge Route Alternate was not adequate for the traffic, and the first section of eight-lane freeway I-5 with a minimum curve radius of opened in 1960. Large parts of the Ridge Route Alternate were incorporated into the new roadway, but the area through the present Pyramid Lake was completely bypassed. I-5 over the mountains between Castaic Junction and Grapevine was completed