By the late 19th century, flour milling and other industries in Georgetown were declining, in part due to the fact that the canals and other waterways continually silted up. Nathaniel Michler and S.T. Abert led efforts to dredge the channels and remove rocks around the Georgetown harbor, though these were temporary solutions and Congress showed little interest in the issue. An 1890 flood and expansion of the railroads brought destitution to the C&O Canal, and Georgetown's waterfront became more industrialized, with narrow alleys, warehouses, and apartment dwellings which lacked plumbing or electricity. Shipping trade vanished between the Civil War and World War I. As a result, many older homes were preserved relatively unchanged.