Streamwatch Project
Middle Branch of White Clay Creek: Site 4
Site 4 is found at Church Hill Road near Creek Road in PA. Like most study sites uncultivated fields, row crops, and forests make up >90% of the landscape in the watershed. Density of people in the area is also at a level typically of most sites in this study. Phosphorus levels are much lower at this site compared to the upstream site (Site 3) suggesting a localized problem upstream. Other water chemistry variables measured do not indicate any obvious impacts (e.g., sewage treatment).
Total macroinvertebrate and EPT density averaged 10,900 individuals/m2 and 700 individuals/m2, respectively. EPT taxa made on average only 11% of the total numbers but up to 41% of the Total Richness (an average of 5 EPT taxa and 11 total taxa/200 individuals). The average MAIS score for the study at Site 4 was in the lower end of the Fair category (6.1). Scores ranged from a low of 3.4 (Poor) in 1995 to a high of 11.3 (Fair) in 2003. Although the MAIS score was the highest in 2003, the following 2 years were extremely low (4.9 and 5.3) and in the Poor category suggesting no long-term improvement in conditions at this site.
| Location | |
|---|---|
| Site number | 4 |
| Description | At Church Hill Road near Creek Road |
| Lat Long (hr min sec) | 39°47.303’ N, -75°48.318’ W |
| Land Use | |
| Watershed area above site (km2) | 31 |
| Population density in 2000 (#/km2) | 140 |
| % Population increase from 1990 to 2000 | 31 |
| Percent pasture/hay | 55 |
| Percent cultivated crops | 24 |
| Percent forest | 14 |
| Chemistry* | |
| Nitrate (mg/L) | 4.98 |
| Ammonium (mg/L) | 0.02 |
| Total Dissolved Phosphorus (mg/L) | 0.078 |
| Soluble Reactive Phosphorus (mg/L) | 0.080 |
| Sulfate (mg/L) | 19.97 |
| Alkalinity (as mg/L CaCO3) | 37.96 |
| pH | 7.94 |
| Conductivity (μmhos) | 212 |
| Dissolved organic carbon (mg/L) | 2.09 |
| Macroinvertebrate Data | |
| years sampled | 1991-1999, 2003-2005 |
| MAIS score | 6.1 |
| water quality based on MAIS score | Fair/Poor |
 Click on macroinvertebrate name to view a photo | |
| 1st most abundant macroinvertebrate | Chironomidae (midges) |
| 2nd most abundant macroinvertebrate | Tipulidae (crane flies) |
| 3rd most abundant macroinvertebrate | Hydropsychidae (common netspinner caddisflies) |
| 4th most abundant macroinvertebrate | Hydroptilidae (microcaddisflies) |
| 5th most abundant macroinvertebrate | Oligochaeta (aquatic worms) |
*See Methods for number of years each chemistry variable was measured.