Baltimore Ecosystem Study

Baltimore Ecosystem Study Data and Metadata

Stream & Watershed - Upper Gwynns Falls Tributaries

From April 1999 to August 2000 Johns Hopkins University graduate student Mark Colosimo sampled a group of sites in the Upper Gwynns Falls watershed that had been studied in the mid-1980’s for his dissertation work. The objective of his work was to evaluate changes in stream physical, chemical and biological properties over time, comparing rapidly suburbanizing tributary subwatersheds (Red Run, Horsehead Branch) with older more stable suburban areas (Scotts Level Branch, Holly Branch).

There were two sites in the Red Run drainage. This watershed drains approximately 19 km2 and has been rapidly suburbanizing since the early 1990s. Percent impervious surface was approximately 10% as of 2002. Sampling station Red Run 1 (RR1) was approximately 35 m upstream of the crossing of Painters Mill Bridge Road, and 350 m upstream of the confluence with the Gwynns Falls. Sampling station Red Run 2 (RR2) was farther upstream, between the Pleasant Hill and Dolfield road crossings.

There were two sites along Scotts Level Branch, an older suburban watershed which was approximately 25% impervious surface in 1970. Site SL1 drains approximately 11 km2 and is located at the outlet of the sub-watershed, just above the confluence with Gwynns Falls. Site SL2 is at the McDonogh Rd. bridge crossing.

The Horsehead Branch (HH) sampling site was located at the McDonogh Road crossing. It drains approximately 5 km2 that has undergone rapid urbanization since the mid 1980s. As of 1997 percent impervious surface was approximately 12%.

The Holly Bank (HB) sampling site was located just upstream of Gwynnbrook Ave. Seventy percent of land in this drainage is classified residential.

The Gwynns Falls at McDonogh (GF5) site was located at the McDonogh school / McDonogh road crossing of the Gwynns Falls and samples a drainage area of approximately 51 km2, with approximately 20% impervious surface.

Please contact Jonathan Walsh, BES Information Manager walshj@ecostudies.org with questions or comments.

This material is based upon work supported by the National Science Foundation under Grant No. 0423476. Any opinions, findings, conclusions, or recommendations expressed in the material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.