Delaware's Watersheds

Riparian Habitat Assessment
Pilot Project




Pike Creek at Three Little Bakers Golf Course - Before

Pike Creek at Three Little Bakers Golf Course - After

Explanation of Data Used in Project

ABBREV.

CM
BSC
E
RQ
FR
SD
VD
BSL
BSR
BVL
BVR
S
RZL
RZR
HCI %
 PARAMETER

Channel Modification
Bottom Substrate/Cover
Embeddedness
Riffle
Frequency of Riffle
Sediment Deposition
Velocity Depth
Bank Stability (Left)
Bank Stability (Right)
Bank Vegetative Type (Left)
Bank Vegetative Type (Right)
Shading
Riparian Zone Width (Left)
Riparian Zone Width (Right)
Total of Above Scores/175 x 100

CLASS DEFINITIONS

SD (Severely Degraded)
MD (Moderately Degraded)
GC (Good Condition)
E (Excellent Condition)
HCI %

0 - 59%
60 - 89%
90 - 99%
≥ 100%
Using funding from the DuPont Clear into the Future Delaware Estuary and Watershed Grants program, the Delaware Nature Society is building on its successful in-stream citizen science program (Technical Monitoring) by establishing a Riparian Habitat Assessment initiative.

The Riparian Habitat Assessment initiative will combine existing/ongoing technical Monitoring chemical data collection with new physical and biological data collection to provide more complete information about the status of water quality in the estuary. The data will also serve as a tool to identify and prioritize areas in need of restoration. The availability of long-term Technical Monitoring data will be crucial to demonstrating concrete changes by data comparison before and after restoration has been implemented.

The trained volunteers collect data on the physical and biological parameters of each site, including a general description of the site, a physical characterization and water quality assessment, and a visual assessment of in-stream and riparian habitat quality. Habitat assessment is performed to determine if a site is capable of sustaining a biological community comparable to a reference.

Macroinvertebrate Survey
The physical and chemical data were supplemented with a macroinvertebrate survey. Macroinvertebrates are those organisms which lack a backbone and are large enough to be seen with the naked eye. Commonly found macroinvertebrates include insects, clams, mussels, snails, worms, amphipods, and crayfish.

In Delaware streams there are thousands of different macroinvertebrate species, each with its own unique requirements for survival. Pollution sensitive organisms require high levels of oxygen and cannot tolerate substantial amounts of toxic substances or habitat degradation. Organisms that can withstand very low oxygen levels, high toxicity and/or poor habitat are known as pollution-tolerant species.

Differences in pollution sensitivity is one of the main reasons macroinvertebrates can be used to assess water quality. Orders that are pollution sensitive include; Ephemeroptera (Mayflies), Plecoptera (Stoneflies), and Trichoptera (Caddisflies). However, families within each of these Orders can vary widely in tolerance. The caddisfly family Hydropsychidae, for example, is relatively pollution tolerant. Therefore identification to family level, or lower, provides a more accurate determination of stream health but is more resource intensive.

The Riparian Habitat Assessment study used a rapid screening approach to characterize the macroinvertebrate community which, combined with the Riparian Habitat data, provides a more comprehensive picture of the stream health and helps to determine sites in need of more in-depth study.

16 Technical Monitoring sites were chosen for this pilot project, four in each of the sub-watersheds. The data collected and the rating each assessed Technical Monitoring site received can be accessed by clicking the appropriate links, below:

Brandywine Creek Watershed:
BC3 - Husbands Run
BC4 - Wilson Run
BC5 - Rocky Run
BC6 - Beaver Run

Christina River Watershed:

 Red Clay Creek Watershed:

White Clay Creek Watershed: