Subjects Urban Development

Black-and-white photo of a man standing in a long trench

Sludge Drying Beds, Essen Nord, Germany

Black-and-white photograph of a man in a hat standing in a brick trench

Grit Chamber, Essen, Germany

Black-and-white image of two cylinders on a white surface

Effects of Expansion of Gas Bubbles in Enscher Sludge Shown in Right-Hand Cylinder

Black-and-white line graph showing two jagged lines on a grid

Diagram Showing Decreased Amount of Dissolved Oxygen in Delaware River, 1913

Water, Water Everywhere – Philadelphia Record, 1937-03-14

Birkinbine Schuylkill Hydrographical Survey 1861-66

Schuylkill River Hydrographical Survey 1861-66 by H. P. M. Birkinbine

Torresdale Conduit work gang, 1906

Torresdale Conduit work gang, 12/18/1906

Cumberland Street pipeline, 1907

Bureau of Water, Cumberland, west of 13th Street, pipe line, 1907

State Street pipeline construction

State Street pipeline construction, 1904

Belmont Filters construction 1903

Belmont Filters construction, 1903

Finished Upper Roxborough filters, 1903

Finished Upper Roxborough filters, 1903

Upper Roxborough filter beds

Upper Roxborough filter beds under construction, July 1902