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The first phase of the state's cleanup
effort on the Leon River below Proctor Lake is nearing completion.
Draft copies of the 31-page "One Total Maximum Daily Load for
Bacteria in the Leon River Below Proctor Lake" will be distributed
and discussed at a meeting in Hamilton set for Thursday, April 17,
at the Hamilton County Courthouse.
The subject area of the TMDL is a 44 mile
stretch of the Leon River beginning about five miles below Proctor
Lake Dam and continuing to just below Highway 281 north of Hamilton.
Proctor Lake water has never been found
to have a bacterial contamination problem and is generally tested on
a daily basis.
The public comment period for the TMDL
runs from April 4 through May 5. The public meeting is scheduled
roughly half way through the public comment period. The plan is
currently available at
www.tceq.state.tx.us/implementation/water/tmdl/34-leon_group.html.
Federal standards define the highest
level of bacteria permitted and the water be deemed fit for human
contact recreation, including fishing, swimming, boating, etc.
TMDL, or total maximum daily load, is a
determination of the relative weightings for sources of bacterial
content, or load, that a given public waterway should be expected to
bear and still meet federal standards. It seeks to define, with some
margin for error, the sources of the entire, or total, bacterial
load.
In addition to defining the sources of
the existing bacterial load, the TMDL also allocates the bacterial
reduction which has to be borne by various sources in a federally
mandated cleanup effort to follow.
In a series of public meetings leading to
the near completion of the first cleanup phase, controversy has
arisen as to the methodologies used by the state in defining the
TMDL. Sampling locations, the inadequate use of testing methods that
relate bacteria to specific sources, the use of an overly complex
computer model to assign bacterial loads as well as the proper
consideration of economic concerns were among the many concerns
expressed in public meetings.
The TMDL assigns the heaviest reduction
loads, by far, on the public wastewater systems of cities of Dublin
and Comanche. Gustine has a share as well. Together they are
referred to in the TMDL as point source loads.
Both Comanche and Gustine are described
as using "mechanical" disinfection methods that employ chlorination,
ordinarily reducing bacteria concentrations to negligible amounts.
Flooding overwhelms these efforts, however.
Dublin uses facultative lagoons, similar
to DeLeon's system. This type of system does not include the use of
a chemical disinfection process. It too is subject to overloading
from flooding. Dublin's system is being assigned a tight water flow
standard below its discharge point.
It was noted in the TMDL that the
likelihood of wastewater effluent containing pathogens is high,
compared to non-human, non-point source loads.
Point source loading, essentially
municipal wastewater plants, is directed in the TMDL to make a 74%
reduction in bacterial discharge.
The percentages vary by city, however.
The percentage reductions by city are: Dublin-85.8%, Comanche-53.1%,
and Gustine-45.9%.
Nonpoint source loading, which basically
includes every other identified bacterial source - urban runoff,
waste application fields, agriculture, rangeland grazing, leaking
septic tanks and sewer mains, wildlife, etc - is mandated to achieve
a 21% reduction in bacterial loading.
The TMDL document does not specify the
measures that will be taken to achieve the bacterial load
reductions, however, but only to define the load, its sources and
how much bacterial load reduction must be achieved.
Once the public comment period has run
and the Texas Commission on Environmental Quality adopts the TMDL,
the next phase will begin, the so-called “TMDL I-Plan” or
implementation plan phase.
The TMDL I-Plan will be developed with
the participation of interested parties, “stakeholders”, and
regulatory agencies. In addition to the TCEQ, the Texas State Soil
and Water Conservation Board and the Brazos River Authority will be
involved in the development of the I-Plan.
Once finally approved, the I-Plan will be
mandatory. It may also be a phased plan with room for adjustment as
subsequent measurements show either improvement or the lack thereof
in the Leon’s bacterial load. |
