Pennypack Park originated in 1910 when the need to provide additional public open space was perceived. By 1916 a significant proportion of the 1,750 acre park was in city ownership. Today the park supports significant areas of natural habitat intermixed with conventional parklands, playgrounds, and athletic fields.
Pennypack Creek has tidal flow up to the Frankford Avenue Bridge where a natural falls has slowed erosion of the river. These falls were the impetus for early development in the area as they acted as a natural dam for mills to draw water from. The first mill built on Pennypack Creek was constructed in 1687 with the creek supporting 30 mills by 1800. These mills grew in size and their affect on the creek continued to increase with the advancements of the industrial revolution. Further impacts on the park were generally limited until Species of Concern documented after World War II when the upper watershed of at Pennypack on the Delaware Park Osprey Pandion haliaetus Bird the area was developed. This greatly decreased Marsh wren Cistothorus palustris Bird the amount of permeable surfaces causing an Halloween pennant Celithemis eponina Dragonfly increase in storm flows and a decrease in base annual wild rice Zizania aquatica Plant flows for the creek. field dodder Cuscuta pentagona Plant multiflowered mud-plantain Heteranthera multiflora Plant river bulrush Schoenoplectus fluviatilis Plant Efforts to increase the amount of permeable salt-marsh water-hemp Amaranthus cannabinus Plant surface within the watershed, increase showy bur-marigold Bidens laevis Plant groundwater infiltration and recharge, and manage subulate arrowhead Sagittaria subulata Plant storm water flows could mitigate the damage done swamp beggar-ticks Bidens bidentoides Plant to the creek and restore some of the lost species and ecological functions.
Pennypack on the Delaware Park Wetland Mitigation Site
Pennypack on the Delaware Park is a mitigation site. This site, formerly a polluted industrial area, was restored to upland grassland and tidal marsh in 2005. Our surveys indicate that the restoration effort has been successful in creating both a warm-season grassland and a functional tidal marsh. We were very surprised at the level of plant diversity present in the tidal marsh. During surveys eight plant species of concern were found along with the Swarty Skipper (Nastra lherminier), a butterfly, and the Halloween Pennant (Celithemis eponina), a dragonfly. It appears that the local seed bank is either still intact or being replenished by Tinicum Marsh and other marshes in the watershed. This would suggest that tidal wetland restoration projects around Philadelphia could expect a significant level of native plant recolonization. One issue of concern at the site was a significant number of non- native invasive species including common reed (Phragmites australis), narrowleaf cattail (Typha angustifolia), and European alder (Alnus glutinosa). These three species are introduced to North America and have the potential to take over and degrade wet sites very quickly. This would be especially detrimental to the rare plants found here and to animals that utilize the open mudflats such as shorebirds. We noted several photo source: Andrew Strassman (PNHP) (PNHP) Strassman Andrew source: photo dozen feeding shorebirds during our survey, indicating Pennypack on the Delaware Park tidal marsh with inset Halloween that this site is important to both local and migratory Pennant (Celithemis eponina) Dragonfly. birds. Overall, this is an excellent site that should work as an example of tidal restoration possibilities in Philadelphia.