LYNCHBURG, Va. (WSET) — The next phase of the Blackwater CSO Tunnel project is underway with crews beginning the installation of the tunnel’s concrete lining.

Lynchburg Water Resources said that once complete, the tunnel will store up to 4.7 million gallons of combined sewage and stormwater during heavy rainfall, significantly reducing overflows into Lynchburg’s waterways.

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Crews are using large steel forms to pour the concrete lining in approximately 75-foot sections between 70 and 120 feet underground.

The tunnel spans 4,744 feet, about 9-tenths-of-a-mile, from the CSO 52 site along the Point of Honor Trail toward the new pump station under construction at the bottom of 7th Street in Downtown Lynchburg.

The Blackwater CSO Tunnel is the largest capital improvement project in Lynchburg’s history.

Lynchburg is expected to reduce the volume of combined sewage and stormwater overflowing into local waterways by 98 percent, according to Lynchburg Water Resources.

The project is expected to be completed next summer. You can track the project on the Tunnel Lining Tracker website. As of Tuesday, 56 feet of the tunnel has been lined with concrete.