Streamwatch Project
Middle Run and Lower Mainstem of White Clay Creek: Site 23
Site 23 on Middle Run is at Delaplane Manor near the north end of Delaplane Road. The stream is accessed by a public walking trail located behind residential homes. This site is also part of the White Clay Creek State Park in DE and is the second most populated watershed in the study; Site 24 upstream on Middle Run is the first. Similar to Site 24 the population density in the watershed has been established since the 1990's. In contrast to the site upstream, there is a large amount of forests and woody wetlands (5%) in the watershed. Nitrate, phosphorus and sulfate levels were low compared to other study sites suggesting minimal impacts from residential areas (e.g., lawn fertilizers).
Total density averaged 5800 individuals/m2 and approximately 80% of the individuals were chironomid midges. Average Total Richness was 13 taxa/200 individuals with 40% of the taxa being EPT. MAIS scores averaged 6.9 (Fair) for the four sample years. MAIS scores suggest water quality is deteriorating at this site: scores went from 10.5 in 2000 to 5.2 in 2005.
| Location | |
|---|---|
| Site number | 23 |
| Description | Middle Run at Delaplane Manor near the north end of Delaplane Road |
| Lat Long (hr min sec) | 39°42.338’ N, -75°43.186’ W |
| Land Use | |
| Watershed area above site (km2) | 9 |
| Population density in 2000 (#/km2) | 449 |
| % Population increase from 1990 to 2000 | 2 |
| Percent pasture/hay | 40 |
| Percent cultivated crops | 13 |
| Percent forest | 27 |
| Chemistry* | |
| Nitrate (mg/L) | 2.67 |
| Ammonium (mg/L) | 0.01 |
| Total Dissolved Phosphorus (mg/L) | 0.013 |
| Soluble Reactive Phosphorus (mg/L) | 0.088 |
| Sulfate (mg/L) | 13.00 |
| Alkalinity (as mg/L CaCO3) | 22.76 |
| pH | 7.52 |
| Conductivity (μmhos) | 177 |
| Dissolved organic carbon (mg/L) | n/a |
| Macroinvertebrate Data | |
| years sampled | 2000, 2001, 2003, 2005 |
| MAIS score | 6.9 |
| water quality based on MAIS score | Fair |
 Click on macroinvertebrate name to view a photo | |
| 1st most abundant macroinvertebrate | Chironomidae (midges) |
| 2nd most abundant macroinvertebrate | Ephemerellidae (spiny crawler mayflies) |
| 3rd most abundant macroinvertebrate | Empididae (dance flies) |
| 4th most abundant macroinvertebrate | Tipulidae (crane flies) |
| 5th most abundant macroinvertebrate | Simuliidae (black flies) |
*See Methods for number of years each chemistry variable was measured.