Tidewater Lock
Interactive map of Tidewater Lock
38°54′00″N77°03′28″W / 38.8999°N 77.0578°W /38.8999; -77.0578
Waterway	Chesapeake and Ohio Canal
Country	USA
State	Washington, D.C.
Operation	Defunct
Length	54 m
Width	4 m

TheTidewater Lock is adam^[1] inWashington, D.C., west of the mouth ofRock Creek at thePotomac River, on the east side ofGeorgetown. Built to connect the Potomac and theChesapeake and Ohio Canal, opened in 1831, it was a busy maritime intersection during several decades of the canal's heyday. C&O documents refer to it as Lock 0 or Tide Lock A. Today, the lock marks Milestone 0 of theNational Park Service's Chesapeake & Ohio Canal trail.^[2]

Canal documents sometimes list a "Tide Lock B" on section "I", completed in 1834 by the lockhouse at 17th and Constitution Ave NW.^[3]

• 
  View of downstream gate pocket where the canal joins the Potomac River
• 
  Ruins of the waste weir, which adjoins the Tidewater lock
• 
  Tidewater lock, with theWatergate complex in the background

• Locks on the C&O Canal

• Chesapeake and Ohio Canal
• Dams in Washington, D.C.
• Georgetown (Washington, D.C.)
• Publicly owned dams in the United States

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