Processing Magazine

Austin celebrates completion of four-mile long wastewater tunnel

October 30, 2012

AUSTIN, Texas — State and local officials gathered in Austin, Texas, today for a ribbon-cutting ceremony to celebrate the completion of one of the largest and most complex wastewater infrastructure projects built by Austin Water over the last decade.

The new four-mile long wastewater tunnel will serve downtown and parts of south Austin, transporting wastewater to Austin Water plants for treatment.

This project is a response to residential and business growth in the city''s downtown corridor. Two major sewer lines in downtown Austin on the north and south shores of Lady Bird Lake were near capacity and had limited ability to take additional sewer flows. The new wastewater tunnel is now taking sewer flows from both the existing lines to provide the additional capacity needed for existing and future growth in central Austin.

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The tunnel replaces aging infrastructure installed more than 50 years ago. Engineers designed the new tunnel using state-of-the-art materials like resin instead of traditional concrete to extend the longevity of the system. The new wastewater infrastructure is expected to last 100 years — twice as long as the old system.

In addition to added capacity, the tunnel construction allowed Austin Water to decommission two lift stations reducing energy consumption and maintenance cost, while freeing up downtown land for other uses including the new central library and more parks.