Mile 174.2 - This well is currently covered by plywood, for safety.  The nearby plaque reads:

A steam pump once stood here to lift water from the Potomac River into the canal during periods of low water.  A pumping station was first built 10 miles downstream opposite the mouth of the South Branch of the Potomac.  This first pump operated for 20 years even though it was inefficient and unreliable during periods of drought.  On several occasions, canal levels dropped so low that cargo weights had to be reduced forcing lost revenue for boat operators.

In 1872 it was recommended that a new pumping station be built 10 miles upstream from the old pump.  Canal Chief Engineer Charles Frisk calculated that the volume of water coming down the Potomac at this point would be sufficient to allow proper navigation in the canal 40 miles downstream.  At that point more water was provided by the impoundment behind dam number 6.

Construction of the steam pump was completed in the late 1870's at a cost of approximately $22,500.  The new construction consisted of a brick boiler room 18.5 x 32 feet and a wooden engine room 23 x 23 feet, constructed on concrete pads.  Two centrifugal pumps were partially submerged in the Potomac, raising 24 cubic feet of water per second 25 feet into a well six feet in diameter and 26 feet high.  A pair of overhead steam engines which operated the pumps were located in the adjoining engine room.

When the water filled the well, it spilled into a concrete flume 6 feet wide and 6.5 feet deep.  Braced and supported by concrete beams, the flume crossed the towpath and supplied water to the canal.

The ruins you see here are all that remains of the application of machinery to supply water to the 184.5 mile long C & O Canal.

This is the flume that carries water from the well to the canal.  At the end of the flume, you can see the well covering and remains of the engine room.