Section 1. The Watershed Today

ENVIRONMENTAL SETTING
The watershed falls into four natural regions or “provinces” whose histories have produced different geologic, topographic, hydrologic, soil and climatic conditions. In turn, they have influenced land use and economic development patterns within the watershed.

Ridge and Valley Province. The northern section of this province, primarily in Schuylkill County, is made up of numerous long narrow mountain ridges separated by valleys of shales and other sedimentary rocks. It provides the resources for the region’s anthracite mining. In contrast, its southern Great Valley section, south of Blue Mountain in Berks County, is a broad lowland with undulating hills and good agricultural soils.

New England Province. Underlain by gneiss, quartzite and other hard rocks, this province (known locally as the Reading Prong), comprises extensively forested hills and ridges and is drained by a network of steep, rocky streams.

Piedmont Province. Underlain by both sedimentary and crystalline rocks, this Province consists primarily of rolling hills and valleys, with extensive branching streams and prime agricultural soils. It encompasses much of the Philadelphia metropolitan area.

Atlantic Coastal Plain Province. Found only in the southern tip of the watershed in the City of Philadelphia, this province comprises gently sloping sands and gravel deposits. Extending into New Jersey, it contains one of the region’s most important groundwater resources.

 

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Site Design: Tevlin & Clarke

 

Headwater tributaries comprise nearly 60 percent of the watershed’s stream miles. First order streams are the smallest. When they join, they become a second order stream. Higher stream orders are formed in the same way, i.e., when two lower order streams join to form a larger one.