Trips Places Foods Stories Newsletters
Loading...
Loading...
Loading...
Loading...

No search results found for
“”

Make sure words are spelled correctly.

Try searching for a travel destination.

Places near me Random place

Popular Destinations

  • Paris
  • London
  • New York
  • Berlin
  • Rome
  • Los Angeles
Trips Places Foods Stories Newsletters
Sign In Join
Places near me Random place
All the United States Washington, D.C. Washington Aqueduct Emergency Pumping Station

Washington Aqueduct Emergency Pumping Station

These abandoned waterworks are crumbling into the Potomac River.

Washington, D.C.

Added By
Elliot Carter
Email
Been Here
Want to go
Added to list
CAPTION
Panorama view   Elliot Carter
Aerial view, looking south   Map Data © Google 2017
Been Here
Want to go
Added to list

About

In 1927, the Dalecarlia Water Treatment Plant opened in the leafy Palisades neighborhood above northwest Washington, D.C. The supervising Army Corps of Engineers were surprised to discover that their aqueduct worked a little too well and was delivering more water than they knew what to do with.

Rather than flush the excess inflow down the drain, the Engineers devised a method of harnessing it to generate electricity, which promised considerable savings on Dalecarlia’s utility bills. Surplus water was channeled downhill through 42-foot pipes and into a small hydroelectric plant. Once it went through the generators it flowed out into the Potomac over a 800-foot “tailrace” spillway.

Over the next four decades the power plant hummed away as planned, but year after year the population of Washington grew, demand increased, and the flow of water down the surplus spillway dropped from a gush to a trickle.

Events escalated to a crisis level on September 9, 1966 as Washington baked under a month-long, late-summer drought. According to Washington Aqueduct General Manager Tom Jacobus, that day, “No water flowed over the Little Falls Dam [intake valves] after the withdrawals upstream and once the Aqueduct’s needs were taken care of. That got people’s attention.” D.C. only had a few-day supply of reservoir water at the time, and if the drought went on much longer water restrictions would be required—a political nonstarter at the time.

Casting around for an emergency stopgap solution, the Engineers’ gaze fell once again on the now-empty hydroplant pipes. Perhaps it would be possible to reverse the thing, install a pump at the bottom and use it as a way to boost the Dalecarlia intake levels. The idea seemed perfect because the spillway connected to the Potomac far enough down river where the water was tidal and it never went dry. 

The 1966 drought ended before construction on the new intake began, (“Blessed Rain,” the Washington Post sighed with relief) but construction proceeded because the project seemed like a prudent idea. The Army Corps of Engineers also proceeded with a longer term reservoir construction program across the city to boost emergency stockpiles.

Back at Dalecarlia, pipes were laid underneath the old spillway that extended the hydroplant’s connection to water’s edge. “A large chamber was blasted into the riverbed and a concrete [slab-like] structure was built around it,” explains Jacobus. In the event of an emergency, generators would be wheeled out onto the concrete pad to feed electricity to submersible pumps down below. Luckily, the long-term expansion of the reservoir system was completed before the Emergency Pumping Station was ever drafted into use, and the pumps were never turned on. 

Its lifecycle as a water outlet and later as an inlet complete, the concrete deck now sits abandoned, slowly crumbling into Mother Potomac. According to Jacobus, "The pad there in the river is mainly used for fishing now, but the Army still owns it."

Related Tags

Waterworks Water Infrastructure Tunnels Government History Abandoned Subterranean Sites

Know Before You Go

Proceed north on the C&O Canal towpath from Georgetown and lookout for the access road / spillway on your left about 600 feet before you hit the DC/MD boundary sign. Proceed with caution after heavy rains, the entire platform can become engulfed by the swollen river.

Community Contributors

Added By

Elliot Carter

Edited By

AF

  • AF

Published

June 23, 2017

Edit this listing

Make an Edit
Add Photos
Sources
  • Interview with Tom Jacobus of the Army Corps of Engineers
Washington Aqueduct Emergency Pumping Station
Chesapeake and Ohio Canal Towpath
Chain Bridge
Washington, District of Columbia, 20016
United States
38.933072, -77.117381
Get Directions

Nearby Places

Washington Aqueduct Chemical Tower

Washington, D.C.

miles away

Arizona Avenue Trestle

Washington, D.C.

miles away

Chain Bridge Road School

Washington, D.C.

miles away

Explore the Destination Guide

Photo of Washington, D.C.

Washington, D.C.

United States

Places 285
Stories 50

Nearby Places

Washington Aqueduct Chemical Tower

Washington, D.C.

miles away

Arizona Avenue Trestle

Washington, D.C.

miles away

Chain Bridge Road School

Washington, D.C.

miles away

Explore the Destination Guide

Photo of Washington, D.C.

Washington, D.C.

United States

Places 285
Stories 50

Related Places

  • Inside the tunnel.

    Payson, Arizona

    Abandoned Mineral Belt Railroad Tunnel

    A partial tunnel blasted into a steep ridge is all that remains of a failed railway across Arizona.

  • The snow sheds.

    Truckee, California

    Donner Pass Summit Tunnels

    The now-abandoned tunnels were built for the transcontinental railroad on the route where the first wagon train entered California.

  • Dashes mark the old tunnel, solid lines are the newer ones

    Washington, D.C.

    Steam Tunnels Under Capitol Hill

    100 years later, they're still down there.

  • The Chemical Treatment Tower

    Washington, D.C.

    Washington Aqueduct Chemical Tower

    Every drop of D.C. tap water flows through this old waterworks.

  • Bottom of the visiting gallery showing the cross-section of the qanat after the fault. The metal structure symbolises the location of the P5 and the gallery digging into the stone.

    Walferdange, Luxembourg

    Raschpëtzer Qanat

    A Roman water tunnel still flows 2,000 years on.

  • Abandoned Eriksdal Train Tunnel.

    Södermalm, Sweden

    Abandoned Eriksdal Train Tunnel

    It was meant to help transport wounded soldiers to a secret underground hospital.

  • Thurgoland Tunnel.

    Thurgoland, England

    Thurgoland Tunnel

    A repurposed railway tunnel with otherworldly acoustic characteristics.

  • Gea de Albarracín, Spain

    Albarracín-Cella Roman Aqueduct

    This ancient tunnel is one of the most important examples of Roman hydraulic engineering in Spain.

Aerial image of Vietnam, displaying the picturesque rice terraces, characterized by their layered, verdant fields.
Atlas Obscura Membership

Become an Atlas Obscura Member


Join our community of curious explorers.

Become a Member

Get Our Email Newsletter

Follow Us

Facebook YouTube TikTok Instagram Pinterest RSS Feed

Get the app

Download the App
Download on the Apple App Store Get it on Google Play
  • All Places
  • Latest Places
  • Most Popular
  • Places to Eat
  • Random
  • Nearby
  • Add a Place
  • Stories
  • Food & Drink
  • Itineraries
  • Lists
  • Video
  • Podcast
  • Newsletters
  • All Trips
  • Family Trip
  • Food & Drink
  • History & Culture
  • Wildlife & Nature
  • FAQ
  • Membership
  • Feedback & Ideas
  • Community Guidelines
  • Product Blog
  • Unique Gifts
  • Work With Us
  • About
  • FAQ
  • Advertise With Us
  • Advertising Guidelines
  • Privacy Policy
  • Cookie Policy
  • Terms of Use
Atlas Obscura

© 2025 Atlas Obscura. All Rights Reserved.