Leslie’s Illustrated Newspaper, Schuylkill Flood 1869
"The equinoctial flood - view of the Schuylkill River at Philadelphia, October 4th 1869. - from a sketch by Fred. B. Schell. - see page 95." Image from Frank Leslie's Illustrated Newspaper, No. 734 - Vol. XXIX, New York, October 23, 1869 [Fairmount Water Works, Dam, Gazebo, Schuylkill Canal, Wire Bridge, Boathouses, Lemon Hill]
From Jane Mork Gibson:
Termed an "Equinoctial Flood," a great freshet occurred on October 4, 1869, and is pictured in Frank Leslie's Illustrated Newspaper of October 23, 1869. The water rose very fast on the Schuylkill to the height of eleven feet five inches above Fairmount Dam. Previously, since the dam's construction in 1822, eight times water over the dam had exceeded six feet. The 1869 freshet surpassed the previous high water mark of ten feet eleven inches of September 2, 1850.
At this time the Old Mill House was being remodeled to house water turbines. Two turbines had replaced water wheels Nos. 2, 3, 4, and 5, and preparations were being taken to replace water wheels Nos. 6 and 7. Frederic Graff, Jr. was the Chief Engineer and his Annual Report for 1869 includes reference to the drought in the summer when steam engines were employed and the freshet in the fall when the height of the water over the dam was the greatest ever (pp. 6-7).
The 1869 summer drought was greater than any experienced since the construction of the dam fifty years earlier. Because the water was so low at the dam, the city faced a crisis in providing water from Fairmount because there was an insufficient supply of. water to operate the wheels. At first, a large wrecking steamer was situated below the dam so that two auxiliary steam pumps could pump water to the reservoirs. This was followed by the city purchasing a pair of large direct acting engines which were placed at the foot of the hill by the forebay and used until the great freshet in October. A small pump house was erected and remained for many years.
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See also page 7 of Annual Report 1869, "Department for supplying the city with water. Annual Report of the Chief Engineer of the Water Department of the City of Philadelphia. Presented to councils February 10, 1870. (2004.057.0057i, 2004.057.0069c, 2004.057.0073, or 2004.057.0477)" for description of river condition.
See also 2008.001.0045A for masthead of newspaper and another image of flooding (in Connecticut.)