How deep would a new tunnel be? How far out into the Pacific Ocean would the new outfall discharge?
In order to minimize or eliminate impacts at the ground surface (e.g., noise, vibration, and utility conflicts), the Sanitation Districts would propose deep tunnel construction utilizing state-of-the-art tunnel boring machines (TBMs).The depth of a new tunnel would fluctuate because of variations in the overlying topography, but, in general, a tunnel could reach depths of 200 feet or more below the ground surface.It is anticipated a new ocean outfall would extend to the continental shelf, at least 1.5 miles off the coast to an ocean depth of approximately 200 feet.
In order to minimize or eliminate impacts at the ground surface (e.g., noise, vibration, and utility conflicts), the Sanitation Districts would propose deep tunnel construction utilizing state-of-the-art tunnel boring machines (TBMs).The depth of a new tunnel would fluctuate because of variations in the overlying topography, but, in general, a tunnel could reach depths up to 450 feet below the ground surface.It is anticipated a new ocean outfall would extend to the continental shelf, at least 1.5 miles off the coast to an ocean depth of approximately 175-200 feet.
