Allegheny River Tunnel (ART)

The second tunnel project in the regional tunnel system.

Stretching approximately 6.2 miles underground, the ART will capture combined sewage from some of the region's largest and most frequent overflow points along the Allegheny River, preventing millions of gallons of untreated combined sewage overflow from reaching the river during rain events.

When complete, the tunnel will connect directly into the Ohio River Tunnel near the Veterans Bridge, forming a critical link in the regional system. The project will span six municipalities — the City of Pittsburgh, Millvale, Etna, Sharpsburg, O'Hara, and Aspinwall, and will include surface facilities to convey the combined sewer flow into the tunnel system below.

The infrastructure built as part of the ART project will address some of the heaviest combined sewer overflow volumes in the region — bringing cleaner water, healthier riverbanks, and improved quality of life to communities along the Allegheny River.