FOSC Chem/Bio WQ Monitoring Summary
December 2017

This is a brief summary of our December 2017 results from chemical and bacterial monitoring at various locations along Sligo Creek.

Bennington Drive
Salinity/TDS/conductivity all remain near their standard winter highs. Chlorine levels and ammonia-N were zero, which is unusual and welcome. Detergent levels, however, were high (4.7 ppm LAS), though down from last month's 6.1. Sound levels were low (40 dB) and air readings were good, but Coliform levels more than tripled from November's readings. No snails, but many birds present. Gray silt in receiving pool now; last month was clean and sandy.

Wayne Avenue
Ammonia-N here was half of last month’s high reading. Salinity, pH and TDS were all slightly below winter averages. Chlorine was low, but detergent level was quite high again (5.6 ppm LAS). Ice surrounded the outfall's surface waters, including a patch of brownish yellow foam frozen into it. Coliform levels were again extremely high. No fish or birds.

Fleetwood Terrace (main channel)
Water temperature (0.1 C) was noticeably lower than at outfalls. Brrr. Detergents were high at 5.7ppm. Free and total chlorine were elevated (.10 and .07 ppm, respectively). Coliform levels ticked back up to the 1000/2000 ECU level. No aquatic life visible, but a beaver dam is well under way and water level upstream is rising.

Maple Avenue
Flow volume moderately strong in 01A and 01B, no flow in 01C. Ammonia-N levels way down to 0.04 and 0.01 mg/L, respectively. Salinity, TDS and conductivity levels were low, but pH was high (+8). Chlorine levels in KE01A were high, but nothing compared to KE01B (3.61 free chorine, 5.01 total chlorine). These levels are higher than commonly found in swimming pools and hot tubs. Surfactants levels were high in both outfalls as well.

On the chemical readings, surfactants (soaps/detergents) everywhere appear to remain persistently high. Sediment was not the pressing issue this time around that it has been for much of the fall. On the biological side, as always, Wayne Avenue produces the highest Coliform readings, and we generally saw some increases in Coliform readings, except at Maple Avenue (the chlorine blast being a part of that).

You can view previous WQ Monitoring Summary reports here:

Results from
Periodic Outfall Monitoring
Along Sligo Creek

FoSC and the Center for Watershed Protection (CWP) Apply Scientific Testing to Improve Sligo Creek

Several outfalls into Sligo Creek are tested periodically by volunteer Pat Ratkowski. Pat tests for ammonia, temperature, and pH to discover illicit discharge problems which may then be reported to the County. An illicit discharge detection and elimination (IDDE) program is a requirement of the County’s Municipal Separate Storm Sewer (MS4) permit. Recent research conducted by the Center for Watershed Protection (CWP) in Sligo Creek and Baltimore City has indicated that illicit discharges are a much greater contributor of nutrient and bacteria pollution than was previously known. Their elimination can help make significant progress towards meeting local and Bay-wide total maximum daily loads (TMDLs). CWP has produced national guidance for developing and implementing IDDE programs, which includes identification of the most appropriate parameters to detect illicit discharges, many of which have sewage components. Volunteers can test for these recommended parameters at outfalls to help find illicit discharges and monitor problematic outfalls over time.

Outfall Photos December 2014

Map of Outfall Monitoring Sites