                  FOR PUBLICATION
  UNITED STATES COURT OF APPEALS
       FOR THE NINTH CIRCUIT

CITY OF ARCADIA; CITY OF                
BALDWIN PARK; CITY OF
BELLFLOWER; CITY OF CERRITOS;
CITY OF COMMERCE; CITY OF
DIAMOND BAR; CITY OF DOWNEY;
CITY OF IRWINDALE; CITY OF
LAWNDALE; CITY OF MONROVIA;
CITY OF MONTEBELLO; CITY OF
MONTEREY PARK; CITY OF PICO
RIVERA; CITY OF ROSEMEAD;
CITY OF SAN GABRIEL; CITY OF
SANTE FE SPRINGS; CITY OF SIERRA
MADRE; CITY OF SIGNAL HILL;
CITY OF SOUTH PASADENA; CITY OF               No. 03-16309
VERNON; CITY OF WEST COVINA;
CITY OF WHITTIER, a California                 D.C. No.
                                            CV-02-05244-SBA
Municipal Corporation,
               Plaintiffs-Appellants,          OPINION
                 v.
UNITED STATES ENVIRONMENTAL
PROTECTION AGENCY; CHRISTINE
TODD WHITMAN, USEPA
Administrator; WAYNE NASTRI,
USEPA Region IX Administrator,
             Defendants-Appellees,
NATURAL RESOURCES DEFENSE
COUNCIL, INC.; HEAL THE BAY, INC.;
SANTA MONICA BAYKEEPER, INC.,
           Defendants-Intervenors-
                           Appellees.
                                        

                             7169
7170              CITY   OF   ARCADIA v. USEPA
        Appeal from the United States District Court
           for the Northern District of California
       Saundra B. Armstrong, District Judge, Presiding

                   Argued and Submitted
          February 10, 2005—Pasadena, California

                    Filed June 15, 2005

   Before: Harry Pregerson, William C. Canby, Jr., and
           Richard C. Tallman, Circuit Judges.

                  Opinion by Judge Canby
                 CITY   OF   ARCADIA v. USEPA          7171


                             COUNSEL

Richard Montevideo, Terence J. Gallagher, Rutan & Tucker,
LLP, Costa Mesa, California, for the plaintiffs-appellants.

John A. Bryson, Department of Justice, Washington, D.C., for
the defendants-appellees.

David S. Beckman, Natural Resources Defense Council, Inc.,
Santa Monica, California, for the defendants-intervenors-
appellees.


                             OPINION

CANBY, Circuit Judge:

  Several municipalities in the Los Angeles area (“Cities”)
challenge administrative actions taken by the Environmental
7172                 CITY   OF   ARCADIA v. USEPA
Protection Agency (“EPA”) pursuant to section 303(d) of the
Clean Water Act, 33 U.S.C. § 1313(d). The EPA established
a total maximum daily load (“TMDL”) that limited the
amount of trash that can be discharged into the Los Angeles
River. The EPA subsequently approved the State of Califor-
nia’s separately established TMDL, which was deemed to
supersede the federal standard. The Cities challenge the
EPA’s authority to approve the State TMDL.1 The district
court dismissed this claim pursuant to rule 12(b)(6) of the
Federal Rules of Civil Procedure for failure to state a claim
upon which relief can be granted. We affirm because we con-
clude that the Clean Water Act permits the EPA’s action.

  I.   Regulatory Background

  In an effort “to restore and maintain the chemical, physical,
and biological integrity of the Nation’s waters,” Congress
enacted the Clean Water Act with the stated “goal that the dis-
charge of pollutants into the navigable waters be eliminated
by 1985.” 33 U.S.C. § 1251(a), (a)(1).

   The Clean Water Act offers two approaches for controlling
water pollution: technology-based regulations and water qual-
ity standards. Technology-based regulations reduce levels of
pollution by requiring a discharger to make equipment or pro-
cess changes, without reference to the effect on the receiving
water. Water quality standards set the permissible level of
pollution in a specific body of water without direct regulation
of the individual sources of pollution.

   The National Pollutant Discharge Elimination System
(“NPDES”) permit program governs implementation of both
technology-based requirements and water quality standards.
33 U.S.C. §§ 1311(b)(1)(C), 1342(a)(1); 40 C.F.R.
§ 122.44(a), (d)(1). An NPDES permit sets specific limits that
  1
   We address the other issues raised on appeal in a separate, unpublished
disposition filed contemporaneously with this opinion.
                  CITY   OF   ARCADIA v. USEPA            7173
apply to individual polluters. Discharges from any “point
source” into the waters of the United States are prohibited
unless that discharge complies with the limits and require-
ments of the NPDES permit. 33 U.S.C. §§ 1311(a), 1362(12),
(14).

   States are required to identify waters where technology-
based effluent limitations and other required controls fail to
achieve water quality standards. 33 U.S.C. § 1313(d); 40
C.F.R. § 130.7(b). This list of substandard waters is known as
the “303(d) list” (section 303 of the Clean Water Act having
been codified as section 1313). States are required to develop
a TMDL for each pollutant of concern. A TMDL is not self-
enforcing, but serves as an informational tool or goal for the
establishment of further pollution controls. See Pronsolino v.
Nastri, 291 F.3d 1123, 1128-29 (9th Cir. 2002).

   The EPA is required to approve or disapprove a State’s
TMDL within thirty days of its submission. 33 U.S.C.
§ 1313(d)(2). If the EPA disapproves a State TMDL submis-
sion, the EPA must issue its own within thirty days of the dis-
approval. Id. The EPA is also under a mandatory duty to
establish a TMDL when a State fails over a long period of
time to submit a TMDL; this “prolonged” failure can amount
to the “constructive submission” of an inadequate TMDL,
thus triggering the EPA’s duty to issue its own. See San Fran-
cisco BayKeeper v. Whitman, 297 F.3d 877, 880-84 (9th Cir.
2002).

  II.   Procedural History

   In 1997, several environmental groups (including Heal the
Bay and Santa Monica BayKeeper) sued the EPA for failure
to satisfy its mandatory duty to establish a TMDL for the Los
Angeles region when California failed to do so. This litigation
resulted in the entry of a consent decree, which required the
establishment of TMDLs to account for all significant sources
of water pollution, including storm water and urban runoff.
7174                 CITY   OF   ARCADIA v. USEPA
The consent decree required EPA either to approve a State-
submitted TMDL for trash in the Los Angeles River water-
shed by March 2001 or, if California failed to make a timely
submission, to establish the EPA’s own TMDL by March
2002.

   California failed to submit a TMDL by March 2001, and
the EPA subsequently established its own trash TMDL for the
Los Angeles River in March 2002. Five months later, Califor-
nia submitted a trash TMDL, and the EPA subsequently
approved it, causing it to supersede the EPA’s TMDL. It is
this approval of California’s superseding TMDL that the Cit-
ies now challenge.2

   The Cities brought this action in the United States District
Court for the Northern District of California. The Cities
claimed that the EPA lacked authority to approve the State
TMDL after having established its own TMDL. The district
court dismissed this challenge pursuant to Fed. R. Civ. P.
12(b)(6) for failure to state a claim.

  III.    Discussion

   [1] We conclude that the EPA acted within the scope of its
statutory and regulatory authority in approving the State
TMDL.3 Neither the Clean Water Act nor its implementing
regulations specify or imply that the EPA is barred from
approving a State submitted TMDL after the EPA has estab-
lished its own. See 33 U.S.C. § 1313(d); 40 C.F.R. § 130.7. In
fact, the States are authorized to submit waters identified and
  2
     The Cities originally challenged the EPA’s TMDL, but that challenge
was withdrawn as moot when it was made clear that California’s TMDL
superseded and nullified EPA’s earlier TMDL.
   3
     We review de novo a dismissal for failure to state a claim pursuant to
rule 12(b)(6) of the Federal Rules of Civil Procedure. Decker v. Advantage
Fund, Ltd., 362 F.3d 593, 595-96 (9th Cir. 2004). Dismissal is proper
when there is a “lack of a cognizable legal theory” to support a claim. Bal-
istreri v. Pacifica Police Dep’t, 901 F.2d 696, 699 (9th Cir. 1990).
                   CITY   OF   ARCADIA v. USEPA              7175
TMDLs “from time to time” and the EPA is required either
to approve or disapprove a TMDL upon submission by a
State. 33 U.S.C. § 1313(d)(2) (“The Administrator shall either
approve or disapprove such identification and load not later
than thirty days after the date of submission.”).

   [2] This plain reading of section 1313 is consistent with the
basic goals and policies that underlie the Clean Water Act—
namely, that States remain at the front line in combating pol-
lution. See 33 U.S.C. § 1251(b) (“It is the policy of the Con-
gress to recognize, preserve, and protect the primary
responsibilities and rights of States to prevent, reduce, and
eliminate pollution . . . .”); 33 U.S.C. § 1370 (stating that
“nothing in this chapter shall [ ] preclude or deny the right of
any State or political subdivision thereof . . . to adopt or
enforce [ ] any standard or limitation respecting discharges of
pollutants” unless the standard is less stringent than an exist-
ing standard). Even if the language of the statute were not
clear, we would uphold as reasonable the EPA’s interpretation
of the Clean Water Act to require approval or disapproval of
California’s TMDL. See Dioxin/Organochlorine Ctr. v.
Clarke, 57 F.3d 1517, 1525 (9th Cir. 1995) (“A court should
accept the ‘reasonable’ interpretation of a statute chosen by an
administrative agency except when it is clearly contrary to the
intent of Congress.”) (citing Chevron U.S.A., Inc. v. Natural
Res. Def. Council, 467 U.S. 837, 842-44 (1984)).

   The Cities’ reliance on the “constructive submission” doc-
trine is misplaced. It is certainly correct that a State’s failure
to act may trigger the EPA’s duty to establish a TMDL on its
own accord. Nothing in the constructive submission cases,
however, suggests that the establishment of a TMDL by the
EPA divests a State of the ability subsequently to submit a
TMDL on the same subject. See San Francisco BayKeeper,
297 F.3d at 881-83 (discussing the constructive submission
doctrine). Nor does anything in section 1313 suggest that the
EPA is powerless to approve such a submission. See 33
U.S.C. § 1313.
7176              CITY   OF   ARCADIA v. USEPA
   [3] The Cities also argue that the duplicative TMDL pro-
cess violates public policy. There is no legal support for this
argument. The potential for action on both the state and fed-
eral level inheres in the structure of the statutory scheme. So
long as the State does not attempt to adopt more lenient pollu-
tion control measures than those already in place under the
Act, the Clean Water Act does not prohibit state action. See
33 U.S.C. § 1370.

  IV.   Conclusion

   The EPA acted within its authority in approving Califor-
nia’s TMDL despite EPA’s earlier promulgation of its own
TMDL when California originally failed to make a timely
submission. We therefore reject the Cities’ challenge to this
EPA action. By contemporaneous memorandum disposition,
we have rejected the Cities’ other claims against the EPA. We
therefore affirm the judgment of the district court dismissing
the Cities’ action.

  AFFIRMED.
