Mt. Bethel Fens
 
 
 
 
 

Unique wetlands environment is threatened by development. 
Example of a fen. The Mt. Bethel Fen Complex, located in the northeast section of Northampton County, Pennsylvania is a 2,500-acre complex of at least 10 rare wetland communities consisting of small calcareous fens and seeps, marshes and wooded swamps. Fens are open meadow-like, permanently saturated wetlands fed by high pH groundwater. The Mt. Bethel Fens contain an unusual plant community found only in eastern Pennsylvania and New Jersey. Their unique vegetation derives from their extremely alkaline water chemistry (a pH greater than seven) and the cool conditions of the water-soaked soils. The fens at Mt. Bethel are linked by their proximity and, more importantly, by their shared source of water. The amount, quality, and chemical composition of the water are crucial to the fens' existence. If the quality or quantity of the water declines in one fen, it will decline in all of them, damaging or eliminating the delicate fen communities. 

To gain an understanding of the Mt. Bethel Fens, the Lehigh Earth Observatory (LEO), in partnership with The Nature Conservancy, is engaged in a number of projects. These include a water quality assessment program, GPS (Global Positioning System) surveys, the creation and maintenance of a GIS (Geographic Information System) database, and a seismic investigation. The hydrogeologic study monitors water levels and quality from wells placed in the fens. Over time fen water quality, quantity, and the potential recharge sources to the fens can be determined. Included in the analysis are tests for major cations, anions, nutrients, and field measurements such as temperature, pH, and conductivity. A previously conducted seismic investigation provides information regarding the subsurface stratigraphy as well as recharge sources to the fens. By merging the information collected in each of these studies, LEO is able to observe and interpret the processes in this unique and diverse wetland. 
Test wells at site.
Specialized flora unique to fens.

Checking water level in well.
More information @ www.leo.lehigh.edu