SOURCE WATER PROTECTION
Drinking Water Source Protection Through
Effective Use of TMDL Processes
Kenan Ozekin, Water Research Foundation senior research manager
The Clean Water Act (CWA) requires states
to provide opportunities for stakeholder
involvement in the preparation of the 303(d)
list of impaired water bodies where standards
are not being met, and the subsequent total
maximum daily load (TMDL) development
process. Greater involvement in the TMDL
process can yield a number of benefits to
drinking water utilities including improved
source water quality, reduced treatment
processes and costs, reduced disinfection
by-products, increased reservoir volumes,
and good public relations.
Recognizing these benefits, Water Research
Foundation order/project #4007 was funded
with the goal to provide water utilities with
information and tools that help them better
understand and use the TMDL process so
they can protect and improve their source
water quality. The project’s goal was achieved
by pursuing two objectives: ( 1) to identify
successful strategies used by utilities to
protect their source waters through the TMDL
regulatory process, and ( 2) to identify specific
measures that are being used to include
drinking water objectives in TMDLs.
The project developed seven case studies
for utilities that have been involved or
are preparing to get involved with the
development of TMDLs for their source
waters. As part of those case studies,
successful strategies used by the utilities
were identified, as were missed opportunities.
These helped the research team to develop
user-friendly information and tools such
as a step-by-step description of the TMDL
process and how utilities can get involved,
a flow chart to help utilities to get started
with the TMDL process, a sample letter for
utilities to use to request involvement in the
TMDL process, and useful TMDL Websites.
Based on the project findings, the following
recommendations were made to drinking
• Understand that a TMDL may be under
development for your source water based
on impairment of a designated use other
than it being a drinking water supply.
Consider this an opportunity to get involved
• Check that your surface water source has
been properly categorized by the state as a
drinking water supply.
• Review the state ambient water quality
standards (WQS) for drinking water
supplies to see if your source water fails to
meet any of those standards.
• Approach the TMDL development process
with an understanding of state WQS and
how they relate to drinking water standards.
• Participate in the TMDL development and
• Be proactive. Early involvement in the
TMDL process will increase opportunities
for water utilities to effectively
communicate with interested parties and
will allow the utility to provide input on its
water quality goals and needs.
• Share data and information with