Public Workshop Held on Murderkill River TMDL Regulation Amendments

The Watershed Assessment Section of the Department of Natural Resources and Environmental Control (DNREC) held a public workshop on proposed amendments to the 2001 Murderkill River total maximum daily loads (TMDL) regulation on Thursday, August 12 at the Felton Fire Hall.  About 30 people attended, including several Tributary Action Team members, DNREC staff, employees of the Kent County Wastewater Treatment Facility, and residents.  Three presentations and a poster display provided comprehensive information on the proposed changes.

The 2001 TMDL regulation requires reductions of nitrogen and phosphorous as well as oxygen consuming compounds to meet Delaware’s water quality standards and nutrient targets.  The Kent County Levy Court, owner and operator of the Kent County Wastewater Treatment Facility, appealed the original regulation.  As a result of the appeal, DNREC agreed to collect additional field data and, if the results warranted, modify the model so that its predictions would more closely agree with field observations.

The results of two field studies conducted in 2002 revealed that the model was underestimating stream cross-sectional areas, tidal currents and discharge flows for the Lower Murderkill River. This essentially means that the lower part of the river can assimilate higher loads of nutrients than originally estimated by the model.  The new information was used to update the model and a revised TMDL has been proposed, increasing the loads of nutrients and oxygen consuming compounds that can be discharged from the Kent County facility.  It also takes into consideration that surface discharge from the Harrington facility will be eliminated through the use of spray irrigation, except during winter months when irrigation isn't feasible.  The proposed revision does not change nonpoint source pollution load reduction requirements.

Participants were concerned that the proposed amendments to the TMDL would allow the Kent County facility to discharge more phosphorus into the Murderkill River than what was allowed under the 2001 TMDL.  The assumption that the Harrington facility will be changing their operation to include spray irrigation was a concern because those plans had not been finalized prior to the workshop.

Participants were also interested in addressing the nutrient issues by river segment, and part of the poster display showed nutrient loading for different parts of the river.  The TMDL data shows that some sections have higher nutrient loads than others, due to activities that are occurring on the adjacent land or upstream.

The next step in this process is a public hearing, which will be held at a time and location to be announced at a later date. Please feel free to check our calendar for updates.

The following documents are available for your downloading and review:

Draft Technical Analysis for Amendment of the
2001 Murderkill River TMDLs
Adobe Acrobat version (1.8 MB) FlashPaper version (1.3 MB)

Acoustic Doppler Current Profile Study of the Tidal Murderkill River, Kent County, Delaware, Conducted September 21 and 29, 2002
Adobe Acrobat version (650 kb) FlashPaper version (640 kb)

Murderkill River WASP Model Modification Report
Adobe Acrobat version (2 MB) FlashPaper version (23 MB)