DC Water Opens the West Potomac Park Construction Site to the Public for Tours, Activities and More

Ever wonder what it takes to build a 5.5-mile tunnel beneath the nation’s capital? On Saturday, September 19, DC Water invites the community for a rare opportunity to experience one of the District’s largest infrastructure projects up close and underground.

We’re opening the West Potomac Park construction site for Potomac River Tunnel Community Day from 10:30 a.m. to 3 p.m. You’ll get a chance to explore the active construction site. You can go inside the tunnel, see and touch the equipment, meet our new tunnel boring machine (TBM) Emily, and enjoy family-friendly activities for all ages.

If you want to take the trip deep underground, we’re offering a limited number of pre-registered tunnel tours. You’ll be lifted by a crane and descend 105 feet into the main shaft — about 10 stories below ground.  There you’ll get to walk a short distance into the tunnel for a firsthand look at the massive underground construction operation.

Inside the tunnel, Emily’s sister TBM Mary, is already hard at work. She is tunneling the 2.4 miles north toward Georgetown University, Emily will mine approximately 3.1 miles south from West Potomac Park toward Joint Base Anacostia-Bolling. There the Potomac River Tunnel will connect with the existing Anacostia River Tunnel.

The Potomac River Tunnel is a 5.5-mile tunnel designed to capture combined stormwater and sewage during heavy rain, reducing overflows into the Potomac River and improving water quality. The tunnel is scheduled to begin operating in 2030.

Community Day Details

What: Potomac River Tunnel Community Day
When: Saturday, September 19, 2026, from 10:30 a.m. to 3 p.m.
Where: West Potomac Park Construction Site on West Potomac Park Drive SW (between Independence Ave and Ohio Dr SW – GPS address 1601 Ohio Drive SW) Look for the large cranes!

Attendees are strongly encouraged to RSVP at prtcommunityday.rsvpify.com, are required to wear fully enclosed, flat shoes, and sign a liability release form.

IMPORTANT: Want to Go Underground?

Advance registration is required for underground tunnel tours. Space is extremely limited. Participants must be at least 18 years old, wear long pants, closed toed shoes, and socks. A signed waiver is required and mandatory safety orientation before the tour. DC Water will provide all required personal protective equipment.

Register for an underground tour:
prtcommunityday.rsvpify.com 

For additional information, email dcpotomacrivertunnel@dcwater.com.

Learn more about the Potomac River Tunnel Project at dcwater.com/prt.