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Cobbs Creek Watershed History

Bridge over Cobbs Creek at Whitby Avenue. Built by members of the Sherwood Improvement Co. Date not noted, probably ca. 1900. Free Library of Philadelphia Print & Picture Collection

The settlement of Philadelphia began along the Delaware River in the 17th century and slowly crept westward. It was not until the late 19th century that dense urban development reached the watershed of Cobbs Creek, which forms part of the western boundary of the city. Long before then, Dutch, Swedish and finally the English and German immigrants inhabited and farmed in the area beginning in the mid-17th century. The oldest mill in Philadelphia, built by the Swedish settlers on Cobbs Creek in 1642, stood just upstream from where Woodland Avenue now crosses the creek. By the 19th century, dozens of other water-powered mills - producing flour, paper, textiles, and other products - had set up shop along Cobbs Creek and its major tributaries, Naylor's Run and Indian Creek.

Main transportation routes to and through the watershed included several turnpikes that followed the diagonal routes of the current Woodland, Baltimore and Lancaster avenues. Several railroads with both freight and passenger service were built in the decades before the Civil War, and afterwards trolleys (first horse-drawn and later electric) served to spur residential development in the areas they served.

Mills along Indian Creek near 69th Street and Haverford Avenue, 1915. Photograph by John W. Eckfeldt. Note the rows of houses built up to the edge of the valley. This mill, situated at the confluence of the east and west branches of Indian Creek, was eventually torn down, and the playing fields in Morris Park were built on the filled and leveled location. Free Library of Philadelphia Print & Picture Collection

Development Pattern

The wholesale transformation of the watershed - from mostly open farmland, meadows and woodland with scattered villages and small industrial centers into a mostly developed residential area - began in the later part of the 19th century. Two infrastructure projects stimulated this transformation. The completion of the Mill Creek sewer in West Philadelphia in 1895, which obliterated the stream and its valley, allowed the urban grid of streets and residences to continue unimpeded toward Cobbs Creek. In 1908, the completion of the Market Street section of the Market-Frankford Elevated Railroad, or the “El,” allowed quick access into the city for suburban dwellers and greatly spurred residential construction in the western parts of Philadelphia and eastern Delaware County. Between 1910 and 1930, 2,000 new houses a year were built in West Philadelphia, with similar housing booms occurring somewhat later in the suburban communities closest to the city, including Yeadon, Darby, and Upper Darby.

By the 1930s, most of the factories in the watershed had closed, leaving abandoned buildings as the main reminder of the area's once-thriving industrial heritage. Residential development continued to spread, with large sections of Overbrook Park in Philadelphia built up after World War II, and continuing into Haverford and Lower Merion Townships in the 1950s and 1960s, although at a considerably lower density.

Woodland Avenue at Cobbs Creek, looking upstream. Old bridge, left, on October 22, 1908. Note the open sewer emptying its contents into the creek. This old bridge was replaced by a new concrete bridge (left), shown in 1909. Philadelphia City Archives

Development Leads to Stream Degradation

As in other parts of the city, rapid urbanization led to the degradation of stream quality in several ways. Several Cobbs Creek tributaries within Philadelphia were encapsulated in combined sewers, the largest being Thomas Run. Also known as Ameaseka Creek, this stream had its source near 53rd and Walnut streets and flowed into Cobbs Creek at about 60th Street. Thousands of feet of Naylor's Run in Upper Darby Township were channeled into underground culverts to facilitate commercial and residential development in the filled land above the pipes. A massive increase in impervious surfaces in the watershed meant that runoff reached the creek more quickly, leading to higher storm flows, and increased erosion and scouring of the stream banks and bed. Sewers from the new neighborhoods in the watershed emptied directly into the creek and its tributaries, polluting the water with raw sewage. By 1914, Philadelphia had constructed an interceptor sewer that captured wastes and prevented them from entering the creek, but it took decades longer before communities in neighboring Delaware and Montgomery counties did the same. In more recent times, combined sewer overflows, polluted stormwater runoff and inadequate drainage systems, leaking and inadequate septic tanks, lack of open space for recreation, illegal dumping, and an array of other urban ills have also taken their toll on the quality of human and natural life in the watershed.

Open Space Preserved

Beginning in the mid-19th century, a number of cemetery companies bought up large tracts of the watershed, establishing Mt. Moriah, Fernwood, Holy Cross, and Arlington cemeteries. As the farmsteads in the watershed, one by one, were subdivided and transformed into residential neighborhoods, these cemeteries kept hundreds of acres of open space out of the hands of real estate developers. The creation of Cobbs Creek Park in the beginning of the 20th century preserved hundreds of acres of open space in Philadelphia and Delaware counties. The donation of Morris Park to the city preserved Indian Creek from being encapsulated in an underground sewer, which had been proposed for this stream by 19th-century city planners. The long-fought battle to preserve a section of Tinicum Marsh finally ended with its elevation to the status of National Wildlife Refuge, providing another natural respite in the tidal reaches of the watershed. A final battle was fought by residents of the watershed against plans to blast an expressway through the Cobbs Creek valley. Interstate 695 would have begun at I-95 near Essington and connected with another expressway at Whitby Avenue in West Philadelphia. These plans were killed in the mid-1970s, with the money diverted into mass transportation projects.

Cobbs Creek in 1880, location not noted. Photograph by John W. Eckfeldt. Free Library of Philadelphia Print & Picture Collection