Value Engineering (V.E.) Team Study on this 5km long, 5.5m. diameter twin tunnel transit system. The PCC bridge structure spans the Don River. The Twin Tunnels Project (Leslie Station to Bonnington Place & Buchan Creek to Don Mills Station) was designed as twin circular tunnels from a shaft immediately west of the GO Transit line at Leslie Station to Bonnington Place, a distance of 3,250 meters.
