Sen. Aaron Osmond is proposing legislation to allow a toll road â or perhaps a toll tunnel â to improve a now-tricky shortcut through the Oquirrh Mountains between Tooele and southern Salt Lake County. There already is a public road there, paved through Butterfield Canyon in Salt Lake County. But itâs just a dirt byway in Middle Canyon in Tooele County, said Gordon Haight, assistant Herriman city manager and a chief proponent of improving the route. âIt is winding and steep,â Haight said.