Streamwatch Project
East Branch of White Clay Creek: Site 16
Site 16 is situated on the White Clay Creek Preserve, downstream from Good Hope Road and the bridge on Broad Run. Land cover is mostly pasture with some forests and agriculture. The number of people living in the watershed has nearly doubled from 1990 to 2000, but as of 2000 it was still at a density comparable to the study average. Like other sites on the East Branch, alkalinity and conductivity are high compared to the West, Middle, and Lower reaches.
Total macroinvertebrate density averaged 8200 individuals/m2 between 1991 and 2005. This site was considered Poor on all of the 11 sample dates, with an average MAIS score of 3.8. EPT Richness (2 taxa/200 individuals) and % EPT (9%) were extremely low compared to Site 11, the reference site. Macroinvertebrates characterized this as one of the worst sites and indicate it has shown no improvement since 1991.
| Location | |
|---|---|
| Site number | 16 |
| Description | On the White Clay Creek Preserve, downstream from Good Hope Road and the bridge on Broad Run |
| Lat Long (hr min sec) | 39°45.764’ N, -75°45.998’ W |
| Land Use | |
| Watershed area above site (km2) | 83 |
| Population density in 2000 (#/km2) | 168 |
| % Population increase from 1990 to 2000 | 41 |
| Percent pasture/hay | 52 |
| Percent cultivated crops | 16 |
| Percent forest | 17 |
| Chemistry* | |
| Nitrate (mg/L) | 4.54 |
| Ammonium (mg/L) | 0.03 |
| Total Dissolved Phosphorus (mg/L) | 0.094 |
| Soluble Reactive Phosphorus (mg/L) | 0.085 |
| Sulfate (mg/L) | 38.8 |
| Alkalinity (as mg/L CaCO3) | 92.81 |
| pH | 8.32 |
| Conductivity (μmhos) | 352 |
| Dissolved organic carbon (mg/L) | 3.12 |
| Macroinvertebrate Data | |
| years sampled | 1991-2001, 2003-2005 |
| MAIS score | 3.8 |
| water quality based on MAIS score | Poor |
 Click on macroinvertebrate name to view a photo | |
| 1st most abundant macroinvertebrate | Chironomidae (midges) |
| 2nd most abundant macroinvertebrate | Oligochaeta (aquatic worms) |
| 3rd most abundant macroinvertebrate | Hydropsychidae (common netspinner caddisflies) |
| 4th most abundant macroinvertebrate | Tipulidae (crane flies) |
| 5th most abundant macroinvertebrate | Elmidae (riffle beetles) |
*See Methods for number of years each chemistry variable was measured.