March 30, 2015

Honorable Gina McCarthy 

Administrator 

U.S. Environmental Protection Agency 

1200 Pennsylvania Avenue, N.W. (1101A) 

Washington, D.C. 20460

Dear Administrator McCarthy,

The purpose of this letter is to request increased consultation with states by

the Environmental Protection Agency (EPA) during development of 

regulatory efforts regarding tribal authority under the Clean Water Act

(CWA). Because states and the EPA work together as co-regulators under 

the CWA, we urge you to endow states with an early and meaningful role 

in the development of regulations that could have significant consequences 

for water quality management.

In particular, Western Governors urge greater state consultation by EPA in 

development of: (1) an interpretive rule that will outline the process by 

which tribes obtain “Treatment in a Similar Manner as a State” (TAS) 

status, and (2) a separate formal rule that will establish a program for tribal 

administration of Total Maximum Daily Load (TMDL) standards, pursuant 

to Section 303(d) of the CWA.

Western Governors recognize that Section 518(e) of the CWA directs the 

EPA to promulgate regulations on tribal TAS authority for CWA programs.

We request that the Agency engage in thorough consultation on these TAS 

proposals with the western states, which typically have a larger tribal 

presence than other states and a greater likelihood of conflicting water 

standards.

Many western states count a dozen or more Indian tribes within their 

boundaries. When EPA grants TAS authority to tribes, water bodies

currently regulated by states may become subject to duplicative — and 

potentially conflicting — standards. This creates a more complicated 

regulatory environment for water managers and users.

Congress clearly intended to avoid this outcome. We commend to your 

attention the following portion of CWA Section 518(e):

The Administrator shall, in promulgating such regulations,

consult affected States sharing common water bodies and 
Honorable Gina McCarthy 

March 30, 2015

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provide a mechanism for the resolution of any unreasonable consequences that 

may arise as a result of differing water quality standards that may be set by 

States and Indian tribes located on common bodies of water. Such mechanism 

shall provide for explicit consideration of relevant factors including, but not limited to, 

the effects of differing water quality permit requirements on upstream and downstream 

dischargers, economic impacts, and present and historical uses and quality of the 

waters subject to such standards. Such mechanism should provide for the avoidance 

of such unreasonable consequences in a manner consistent with the objective of this Act

(emphases added).

Congress’ imperative to avoid potential conflicts can only be achieved if states have a 

substantive role in the development of the proposals for tribal TAS authority and in future 

tribal action under the CWA.

The Western Governors appreciate EPA’s outreach to state associations regarding these 

rulemaking efforts in the fall of 2014. We now ask for EPA to directly consult with the states on

the specific provisions of the proposals for tribal TAS authority before they are drafted and 

released to the public for comment. It is through this type of collaboration that we will be able 

to best protect the waters of the West.

Respectfully,

Brian Sandoval

Governor, State of Nevada

Chairman, Western Governors’ Association