Save Our Springs Alliance, Inc. v. Texas Commission on Environmental Quality and the City of Dripping Springs

Supreme Court of Texas
══════════
No. 23-0282
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Save Our Springs Alliance, Inc.,
Petitioner,

v.

Texas Commission on Environmental Quality and
The City of Dripping Springs,
Respondents

═══════════════════════════════════════
On Petition for Review from the
Court of Appeals for the Eighth District of Texas
═══════════════════════════════════════

Argued October 1, 2024

JUSTICE DEVINE delivered the opinion of the Court.

Save Our Springs Alliance, Inc. (SOS) challenges a final order of
the Texas Commission on Environmental Quality (TCEQ) granting the
City of Dripping Springs a permit to discharge treated wastewater into
Onion Creek. Although myriad concerns have either been resolved or
abandoned, the parties remain at odds over the proper construction and
application of TCEQ’s “antidegradation” rules and implementation
procedures. 1 The central conflict concerns TCEQ’s practice of assessing
“degradation” of water quality by evaluating impacts on the water body
as a whole rather than affording decisive weight to numeric changes in
individual water-quality parameters.
By TCEQ rule, “degradation” means “a lowering of water quality
by more than a de minimis extent.” 2 When deciding whether a proposed
discharge will result in degradation, TCEQ consults multiple
water-quality parameters to determine whether the discharge will cause
an overall “lowering of water quality.” Under this approach, numeric
changes to one or more parameters may or may not equate to
degradation. SOS reads the antidegradation rules as commanding a
strict “parameter-by-parameter” approach, under which a cognizable
change to even a single water-quality parameter is fatal to permit
approval. In SOS’s view, TCEQ was not authorized to issue the
discharge permit because predictive modeling shows dissolved oxygen
levels in Onion Creek will reduce from at least 6.44 mg/L to 5.0 mg/L,
which is more than a de minimis change in that parameter.

1 See 30 Tex. Admin. Code §§ 307.3(67) (defining standards implementation

procedures), .5 (antidegradation policy and implementation procedures);
Water Quality Division, Procedures to Implement the Texas Surface Water
Quality Standards (RG-194) (June 2010) (the “2010 IPs”),
https://www.tceq.texas.gov/downloads/permitting/water-quality-standards-im
plementation/june-2010-ip.pdf; see also TEX. WATER CODE § 26.023 (“The
commission by rule shall set water quality standards for the water in the state
. . . [and] has the sole and exclusive authority to set water quality standards
for all water in the state.”).
2 30 Tex. Admin. Code § 307.5(b)(2).

2
The court of appeals upheld the permit’s issuance, 3 and we affirm
its judgment. TCEQ’s practice of assessing a water body’s overall
quality conforms to the regulatory requirements as they are written. We
are also unpersuaded by SOS’s additional argument that TCEQ’s final
order is invalid for failure to include a “statement of the underlying
facts” supporting TCEQ’s ultimate fact findings. 4
I.
A. The Disputed Discharge Permit
The City of Dripping Springs is rapidly outgrowing its current
land-application wastewater permit, under which it may use treated
water only to irrigate designated irrigation fields. To accommodate an
expanding populace and plan for future needs, the City filed an
application with TCEQ in 2015 for a permit to discharge up to 995,000
gallons per day of treated wastewater into two nearby waterways. 5
Initial discharges would be made into Walnut Springs and then travel
approximately .43 miles to Onion Creek. This appeal focuses only on
Onion Creek.

3 668 S.W.3d 710, 716 (Tex. App.—El Paso 2022).

4 See TEX. GOV’T CODE § 2001.141(b), (d) (distinguishing between findings

of fact and a statement of underlying facts).
5 See TEX. WATER CODE § 26.027(a), (b) (authorizing TCEQ to issue permits

to discharge waste or pollutants into or adjacent to state water and specifying
minimum application requirements); 30 Tex. Admin. Code §§ 305.42, .45 .48
(requiring an application for a wastewater discharge permit). TCEQ’s exercise
of the state-law permitting authority granted by section 26.027 of the Water
Code is part of a multi-layered federal–state regulatory regime, the details of
which are not important here. See generally 33 U.S.C §§ 1251–1389.

3
TCEQ rules prescribe antidegradation standards for permitted
discharges into three tiers of waterways. 6 The following two are
relevant to high-quality waterbodies like Onion Creek:
Tier 1. “Existing uses and water quality sufficient
to protect those existing uses must be maintained. . . .”

Tier 2. “[1] No activities subject to regulatory action
that would cause degradation of waters that exceed
fishable/swimmable quality are allowed [2] unless it can be
shown to [TCEQ’s] satisfaction that the lowering of water
quality is necessary for important economic or social
development. [3] Degradation is defined as a lowering of
water quality by more than a de minimis extent, but not to
the extent that an existing use is impaired. Water quality
sufficient to protect existing uses must be maintained.
[4] Fishable/swimmable waters are defined as waters that
have quality sufficient to support propagation of
indigenous fish, shellfish, terrestrial life, and recreation in
and on the water.” 7

Under these standards, TCEQ may issue a waterway discharge
permit to the City only if it has determined that the permitted activities
would neither (1) disturb existing water uses nor (2) degrade the water. 8
In making that assessment, TCEQ employs both “narrative” (meaning

6 30 Tex. Admin. Code § 307.5(a), (b). The language in Texas’s
EPA-approved water-quality standards is similar but not identical to federal
regulations. 40 C.F.R. § 131.12.
7 30 Tex. Admin. Code § 307.5(b)(1), (2). Tier 3 applies only to “outstanding
national resource waters.” Id. § 307.5(b)(3).
8 Id. §§ 307.5(b)(1), (2); see id. §§ 307.7(b) (establishing categories of uses),

.10(1) (App’x A) (assigning site-specific uses and criteria for classified
segments, including Onion Creek).

4
qualitative) and “numeric” (meaning quantitative) criteria. 9 Some
water-quality parameters are subject only to general narrative criteria.
For example, nutrients in permitted discharges, like total phosphorous
(TP) and total nitrogen (TN), “must not cause excessive growth of
aquatic vegetation that impairs an existing, designated, presumed, or
attainable use.” 10 The permitting standards assign no specific numeric
criteria to these nutrients. But numeric criteria are applicable to
various other water-quality parameters, including temperature,
indicator bacteria, total dissolved solids, and—relevant here—dissolved
oxygen (DO) concentrations. 11
For classified segments like Onion Creek, general numeric
criteria are superseded by site-specific criteria. 12 For example, the
general DO criteria for water with high aquatic life can range from a
mean of 4.0 to 5.5 mg/L, 13 but the site-specific criterion for Onion Creek

9 Id. §§ 307.4, .7, .10(a); see id. § 307.3(17) (defining “criteria” as “water

quality conditions that are to be met in order to support and protect desired
uses, i.e., existing, designated, attainable, and presumed uses”), (44) (defining
“nutrient criteria” as “numeric and narrative criteria that are established to
protect surface waters from excessive growth of aquatic vegetation”),
(66) (defining “standards” as “desirable uses (i.e., existing, attainable,
designated, or presumed uses as defined in this section) and the narrative and
numerical criteria deemed necessary to protect those uses in surface waters”).
10 Id. § 307.4(e).

11 Id. §§ 307.4, .7, .10; see 2010 IPs, supra note 1, at 56-57.

12 30 Tex. Admin Code §§ 307.4(a), .10(1) (App’x A) (Segment No. 1427,

Onion Creek).
13 Id. § 307.7(b)(3)(A)(i); see id. §§ 307.4(h)(2) (“Aquatic life use categories

and dissolved oxygen criteria for classified segments are specified in Appendix
A of § 307.10 of this title.”), .10(1) (App’x A) (“Dissolved oxygen criteria are
listed as minimum 24-hour means at any site within the segment. Absolute

5
is a mean of 5.0 mg/L. 14 Modeling the City submitted in support of its
permit application showed that the proposed discharge would likely
cause DO to drop from levels exceeding 6.44 mg/L at critical temperature
to at or just below 5.0 mg/L at the discharge point, while rising to
baseline levels almost immediately thereafter. The City believed this to
be sufficient to meet Onion Creek’s site-specific DO criterion. 15
When TCEQ’s Executive Director (ED) determined that the
permit application was “administratively complete,” the City provided
public notice of its intent to obtain a permit. 16 TCEQ then commenced
a “technical review” of the application to ensure compliance with
applicable water-quality standards, including the antidegradation

minima and seasonal criteria are listed in § 307.7 of this title unless otherwise
specified in this appendix.”).
14 Id. § 307.10(1) (App’x A) (Segment No. 1427, Onion Creek) (designating

site-specific uses and criteria for Onion Creek, including high aquatic-life use,
minimum 24-hour mean DO, and maximum annual averages for chloride,
sulfate, and total dissolved solids); see id. § 307.4(g)(2), (h)(2).
15 The City’s two QUAL-TX models predicted post-discharge DO levels of

5.04 mg/L and 4.87 mg/L. The City’s environmental engineer explained that
the lower result was nonetheless “complian[t] with the assumed dissolved
oxygen criterion of 5 mg/L, as TCEQ normally assumes a departure of 0.2 mg/L
as compliant.” Whether any variance is allowable is the subject of dispute
among the parties, but on the record before the Court, we need not, and
therefore do not, consider the matter.
16 See TEX. WATER CODE § 5.552(a), (b); 30 Tex. Admin. Code § 39.551.

6
rules. 17 The review included DO modeling to predict how the proposed
discharge would affect DO in the receiving waterways. TCEQ
determined that the discharge permit would require more restrictive
effluent limits than those proposed by the City—specifically, lower
levels of nutrients (TP and TN) and increased levels of DO. With these
adjustments in place, TCEQ’s modeling predicted that DO in Onion
Creek would not reduce to less than 5.0 mg/L. TCEQ also recommended
adding a disinfection requirement to minimize any impact on the Barton
Springs Salamander.
The ED issued a preliminary decision granting the application, 18
along with a draft permit incorporating the recommended adjustments,
which the ED determined to be sufficient to protect existing uses and
prevent degradation of water quality. The draft permit also required
the City to disinfect the wastewater through a dechlorination process
before discharging it. The City accepted these permit constraints and
revised its application accordingly.
The Environmental Protection Agency (EPA) reviewed the draft
permit and the City’s revised application. 19 The EPA also consulted with

17 See TEX. WATER CODE § 5.553; 30 Tex. Admin. Code §§ 307.1–.10 (Texas

Surface Water Quality Standards); 2010 IPs, supra note 1. Certain sections of
the 2010 IPs have not been EPA-approved. See TCEQ, Implementing the Texas
Surface Water Quality Standards in Permitting, https://www.tceq.texas
.gov/permitting/wastewater/implementation (last visited Apr. 3, 2025). As to
those non-approved sections, which are not relevant here, TCEQ review was
performed under the EPA-approved 2003 IPs. Accordingly, we cite only to the
2010 IPs for convenience.
18 TEX. WATER CODE § 5.553(a).

19 See 33 U.S.C. § 1342(d) (providing EPA with authority to review and veto

state approval of any discharge permit that does not comply with federal law).

7
the U.S. Fish and Wildlife Service (USFWS) based on the presence of
the Barton Creek Salamander in the watershed. 20 In December 2016,
the EPA issued interim objections requesting more information about
“whether the state’s analysis complied with TCEQ’s antidegradation
policy and implementation procedures for Tier 2 review.” In January
2017, the EPA forwarded several additional questions following
consultation with USFWS. After receiving a satisfactory response and
supporting documentation from the ED, the EPA withdrew its objections
in June 2017. 21 Referencing the “considerably more stringent” effluent
limits developed during TCEQ’s technical review—including “very low”
TP and TN limits—the EPA determined that the Tier 1 and Tier 2
antidegradation standards were satisfied. Referencing TCEQ’s DO
modeling, the EPA definitively stated that any changes to the receiving
water body would be “de minimis (i.e., less than noticeable),” “no
significant degradation of water quality will occur,” and “existing uses
will be maintained in Onion Creek.”

20 16 U.S.C. § 1536 (requiring federal agencies to consult USFWS during

the permitting process to ensure endangered or threatened species are
protected); 2010 IPs, supra note 1, at 21-22 (requiring notification to the
USFWS when permit application screening indicates wastewater discharge
has the potential to affect a listed species); Memorandum of Agreement between
TCEQ and U.S. EPA, Region 6 concerning the [National Pollutant Discharge
Elimination System], section IV.D at 11-12 (June 12, 2020),
https://www.tceq.texas.gov/downloads/permitting/wastewater/municipal/2020
-tpdes-moa.pdf (last visited Apr. 3, 2025) (requiring TCEQ to consult with
USFWS during the permitting process to address potential endangered species
issues in Texas Pollutant Discharge Elimination System permits).
21 33 U.S.C. § 1342(d)(2) (providing that no permit shall issue if EPA timely

objects).

8
While the draft permit was under federal review, the City
published a second notice about the ED’s preliminary decision, which
was set for a public meeting. 22 During the public-comment period, the
ED received comments from 1,087 people related to the draft permit and
provided 160 written responses. 23 In answer to several comments, the
ED outlined the antidegradation review TCEQ undertook and explained
why, in the ED’s opinion, the draft permit met the Tier 1 and Tier 2
standards. After making additional changes to the draft permit in
response to public comments, the ED approved the City’s application in
November 2017.
B. Contested-Case and Judicial-Review Proceedings
Scores of protestants, including SOS, requested a contested-case
hearing to challenge the ED’s preliminary decision and draft permit. 24
TCEQ granted the request, referred the matter to the State Office of
Administrative Hearings (SOAH), and identified twelve issues for

22 See TEX. WATER CODE § 5.553 (requiring the applicant to publish notice

of the preliminary decision and TCEQ to provide by rule a public-comment
period); 30 Tex. Admin. Code §§ 39.551 (rules governing public notice), 55.154
(establishing parameters for public meeting).
23 See TEX. WATER CODE §§ 5.554–.555 (allowing the ED to hold one or more

public meetings and requiring the ED to file “a response to each relevant and
material public comment on the preliminary decision filed during the public
comment period”); 30 Tex. Admin. Code §§ 39.420 (establishing rules for
transmittal of ED’s responses to public comments and decision to designated
people), 55.156 (establishing rules for processing public comments).
24 An “affected person” may request a contested-case hearing to challenge

the ED’s preliminary decision on the permit application. TEX. WATER CODE
§§ 5.115, .555–.556. The applicant and the ED may also request a
contested-case hearing on whether the application complies with all applicable
statutory and regulatory requirements. Id. § 5.557(a), (b).

9
adjudication. 25 Two settlement agreements resolved the dispute as to
all protestants except SOS. The settlement agreements extracted
significant concessions from the City, some of which were then
incorporated into the draft permit and others of which are enforceable
through penalty provisions in the settlement agreements. Among them,
the City agreed to expand infrastructure (with an eye toward avoiding
the necessity of any waterway discharges), 26 reduce the maximum

25 See TEX. GOV’T CODE § 2003.047(e) (governing TCEQ action on a request

for a contested-case hearing); 30 Tex. Admin. Code § 55.211 (same). The issues
designated for the contested-case hearing were: (1) whether the draft permit
contains sufficient provisions to prevent nuisance odors, protect health of the
requesters and wildlife in the area, and protect the requesters’ use and
enjoyment of their property; (2) whether the discharged effluent will violate
the aesthetic parameters in the Texas Surface Water Quality Standards;
(3) whether the draft permit will protect water quality and uses of the receiving
waters under the applicable water-quality standards; (4) whether the proposed
discharge will comply with the applicable antidegradation requirements;
(5) whether the draft permit will protect groundwater in the area; (6) whether
the draft permit should include a requirement for biomonitoring or Whole
Effluent Toxicity testing; (7) whether the proposed treatment process can
satisfy the effluent limits in the draft permit; (8) whether the modeling
analysis of the proposed effluent discharge is sufficient; (9) whether the draft
permit will protect against the creation of algal blooms; (10) whether TCEQ
should deny or alter the terms and conditions of the draft permit based on
consideration of need under Water Code section 26.0282 and the general policy
to promote regional or area-wide systems under Water Code section 26.081;
(11) whether the City’s compliance history raises issues regarding its ability to
comply with the material terms of the permit that warrant denying or altering
the terms of the draft permit; and (12) whether the City substantially complied
with all applicable notice requirements.
26 “Of significance, the City agreed to reduce the need to discharge treated

water into Onion Creek by adding infrastructure so it could use more treated
water to irrigate land and to increase its storage capacity to allow it to better
regulate its discharges. The City’s administrator testified that the City’s goal
was to eliminate all or nearly all discharges into the waterway[.]” 668 S.W.3d
710, 722 n.10 (Tex. App.—El Paso 2022). According to the City’s administrator,

10
allowable discharge under the permit to 822,500 gallons per day, use an
ultraviolet-light disinfection system rather than chlorine, and refrain
from discharging any wastewater at all until wastewater volume
exceeds 399,000 gallons per day. All told, the draft permit has some of
the most stringent effluent limits of any waterway-discharge permit
issued in the State of Texas.
Once the settlement agreements were finalized and the draft
permit revised accordingly, the administrative hearing commenced with
SOS as the sole protestant. 27 When TCEQ’s administrative record was
admitted into evidence, a rebuttable “presumption” arose that the draft
permit (1) “meets all state and federal legal and technical requirements”
and (2) will “protect human health and safety, the environment and
physical property.” 28 SOS attempted to rebut the presumption as to

the City’s existing land-application permit requires disposal of wastewater on
dedicated lands, which does not allow it to fully use the treated effluent on
other land that needs water. She explained that the City’s objective in securing
the discharge permit is to conserve water resources and achieve an
“aggressive” 100% beneficial reuse of wastewater by using the treated effluent
to irrigate parks, medians, golf courses, and other areas rather than
discharging treated effluent into a waterway. See 30 Tex. Admin. Code
§ 210.3(1) (defining “beneficial use” of wastewater); CITY OF DRIPPING SPRINGS,
TEX., CODE OF ORDINANCES §§ 2.04.282, 22.06.007 (2024) (identifying the
City’s 100% beneficial-reuse goal and requiring developers to participate in the
beneficial-reuse program).
27 The other parties to the SOAH proceeding were the City, TCEQ’s Office

of Public Interest Counsel, and TCEQ’s ED.
28 TEX. GOV’T CODE § 2003.047(i-1)–(i-3) (laying out the “prima facie” case,

means of rebuttal, and presentation of additional supporting evidence); 30 Tex.
Admin. Code § 80.17(c) (same). The administrative record included the City’s
permit application, the draft permit, various technical memoranda, the EPA’s
withdrawal-of-objection letter, and the ED’s statement of technical summary,
response to public comment, and preliminary decision.

11
some but not all of the referred issues, and the ED and the City offered
additional evidence, as they were entitled to do. 29 Because most of the
adjudicated issues are not before this Court, we confine our discussion
to the more relevant aspects of the underlying proceedings.
As to Tier 1, SOS argued that increased nutrient loading (TP and
TN) from the permitted discharge would increase algal growth and
cause a drop in DO levels that would negatively impact Onion Creek’s
existing and endangered aquatic species. SOS also cited one of the City’s
modeling results as demonstrating that the permit would disturb
existing uses based on a projected dip in DO to 4.87 mg/L. 30 As to Tier 2,
SOS urged that (1) expected changes in TP, TN, and DO levels are much
more than de minimis and (2) a reduction in DO exceeding 10%
constitutes degradation per se.
After considering documentary evidence, deposition testimony,
and three days of live testimony from the parties’ expert witnesses, the
administrative law judge (ALJ) issued a proposal for decision (PFD)
concluding that the draft permit complied with all requirements for
issuance. The ALJ’s proposed findings of fact and conclusions of law
were accompanied by a 45-page explanation of the legal and evidentiary
bases supporting the ALJ’s determinations as to each of the referred
issues. 31 Among other things, the ALJ determined that (1) the TP, TN,

29 TEX. GOV’T CODE § 2003.047(i-2)–(i-3); 30 Tex. Admin. Code
§§ 80.17(c)(2)–(3), .117.
30 See supra note 15.

31 See TEX. GOV’T CODE § 2003.047(l) (requiring the ALJ to make
“separately stated” “findings of fact, conclusions of law, and any ultimate
findings required by statute”).

12
and DO effluent limits incorporated into the revised permit were
adequate for the authorized discharges to survive Tier 1 and Tier 2
scrutiny; (2) TCEQ followed the appropriate antidegradation review
procedures; and (3) the authorized discharge would comply with the
applicable antidegradation requirements. As the ALJ explained, the
competing evidentiary cases boiled down to a battle of the experts, and
the ALJ found TCEQ’s and the City’s experts to be “more compelling and
reliable” for a variety of reasons, including that SOS’s experts “lacked
experience on the applicable water quality standards and models used
for evaluating the potential impact of wastewater discharges.”
Germane here, the ALJ addressed and rejected SOS’s
“parameter-by-parameter” antidegradation approach as a misreading of
TCEQ’s antidegradation rules. The ALJ observed that the critical
inquiry is whether there is a “lowering of water quality by more than a
de minimis amount,” not whether there has been a mere increase or
decrease in TP, TN, and DO. 32 While increases in nutrients can “be the
primary factor in lowering of water quality,” “a mere increase, standing
alone without additional evidence of its specific impact, does not equate
to a lowering of water quality.” In the same vein, although SOS
considered the change in DO levels significant, SOS failed to show the
change “correlate[d] to a lowering of water quality by more than a de
minimis amount.” On the contrary, the evidence supported the

32 The ALJ provided an illustrative example: “[I]f background TP is .002

mg/L and the discharge would raise that level to .006 mg/L, this would be a
tripling of TP levels—which is clearly more than de minimis. But, the impact
on water quality from such a change in TP may be negligible, because both
.002 mg/L and .006 mg/L may be extremely low.”

13
conclusion that the nutrient and “DO levels in the draft permit are
protective of aquatic life, and any changes have not been demonstrated
to constitute a lowering of water quality in a significant way, which is
the focus of a Tier 2 antidegradation review.” 33
After making minor changes to the ALJ’s recommended findings
and conclusions, 34 TCEQ issued its final administrative order granting
the City’s permit application. The final order included 142 findings of
fact and 22 conclusions of law and expressly adopted the ED’s written
responses to the public comments. 35
SOS sought judicial review of TCEQ’s final order, 36 and the City
intervened. In the judicial-review proceeding, the lower courts came to
different conclusions about TCEQ’s antidegradation review. 37 The trial
court held that TCEQ missed the mark on both its Tier 1 and Tier 2
analyses and, on the pertinent point, summarily agreed with SOS that
Tier 2 antidegradation review requires a parameter-by-parameter
approach rather than a “whole water” approach. The court then
concluded that the record established a Tier 2 violation as a matter of

33 Emphasis in original.

34 See TEX. GOV’T CODE § 2003.047(m) (generally authorizing TCEQ to
amend the proposal for decision so long as the amendment is based on the
administrative record and accompanied by an explanation); Dyer v. TCEQ, 646
S.W.3d 498, 511 (Tex. 2022) (holding that section 2003.047 allows TCEQ to
revisit the record, reweigh the evidence, and revise the ALJ’s findings).
35 See TEX. WATER CODE § 5.557(c); 30 Tex. Admin. Code § 50.117(f).

36 See TEX. GOV’T CODE § 2001.171; TEX. WATER CODE § 5.351.

37 The lower courts also disagreed with one another about the sufficiency of

the public notices, but that issue is not before this Court.

14
law because “undisputed” changes in TP, TN, and DO levels were more
than de minimis. For that reason, the court reversed and enjoined the
final order rather than remanding to the agency to rectify asserted
deficiencies in the Tier 1 fact findings.
In a split decision, the court of appeals reversed and upheld the
permit. 38 The majority held that, “under the statutes and rules . . . as
they are written,” substantial evidence supported TCEQ’s
determination that the discharge permit would neither lower Onion
Creek’s water quality nor impact its existing uses. 39 Like the ALJ, the
majority dismissed SOS’s parameter-by-parameter construction of the
antidegradation policy, observing that both “the existing [Texas Surface
Water Quality Standards] and the EPA-approved [implementation
procedures] provide that an antidegradation review be conducted in a
narrative or qualitative manner, considering several factors in
determining the effect a proposed discharge will have on the receiving
waters.” 40 Accordingly, SOS could not “establish as a matter of law that
a permit violates the antidegradation rules, whether under the Tier 1 or
Tier 2 standards, simply by pointing to evidence that a proposed
discharge would lead to numeric increases in the TP and TN levels in

38 668 S.W.3d 710, 716 (Tex. App.—El Paso 2022).

39 Id. (holding that “TCEQ followed the controlling statutes and its own

rules in resolving the fact intensive questions raised by the permit
application”). The court’s opinion scrupulously details the substantial evidence
supporting TCEQ’s findings and conclusions, see id. at 720, 727-38, but we need
not do so to resolve the legal issues presented here.
40 Id. at 738; see supra note 1; 33 U.S.C. § 1313(c) (governing EPA approval

and triennial review of state water-quality standards).

15
the receiving water.” 41 For similar reasons, the majority dismissed
SOS’s argument that TCEQ was required, but failed, to afford conclusive
weight to anticipated changes in Onion Creek’s DO level. 42
In opining that the permit failed under both tiers, the dissent
employed a parameter-based analysis focusing only on evidence of
nutrient increases that the ALJ had discounted. 43 As the majority
correctly observed, regardless of the proper antidegradation
methodology, the applicable standard of review precludes treating such
evidence as undisputed or binding on the reviewing court. 44
II.
The parties’ debate about TCEQ’s Tier 2 methodology is the
principal issue before us. Because SOS loses on that issue, we further
address—and similarly reject—SOS’s alternative argument that the
final order is fatally defective under section 2001.141 of the
Administrative Procedure Act (APA) based on TCEQ’s failure to detail

41 668 S.W.3d at 738.

42 Id. at 739.

43 See id. at 743-44 (Palafox, J., dissenting) (concluding that the evidence

established “a significantly large increase” in TP and TN levels that would, as
a matter of law, endanger existing aquatic life and lower Onion Creek’s water
quality by more than a de minimis amount).
44 Id. at 738 & n.17 (explaining that (1) any claim that nutrient levels would

raise so significantly would require the court to accept expert-witness
projections the ALJ declined to accept for reasons stated in the PFD and
(2) doing so would be inappropriate under the applicable standard of review);
see TEX. GOV’T CODE § 2001.174 (precluding the reviewing court from
reweighing the evidence).

16
certain “underlying facts” SOS contends are required to support the
final order’s ultimate findings of fact. 45
A. Standard of Review
Under the APA, a court reviewing an agency’s decision in a
contested case “may not substitute its judgment for the judgment of the
state agency on the weight of the evidence on questions committed to
agency discretion.” 46 But a reviewing court must “reverse or remand”
when “substantial rights of the appellant have been prejudiced because
the administrative findings, inferences, conclusions, or decisions” are,
among other things, (1) erroneous as a matter of law; (2) “not reasonably
supported by substantial evidence considering the reliable and
probative evidence in the record as a whole”; or (3) arbitrary, capricious,
or characterized by abuse of discretion. 47 Each of the statutory grounds
for reversal, including substantial-evidence review, is a question of law
subject to de novo review. 48
“Substantial evidence” is “a limited standard of review that gives
significant deference to the agency in its field of expertise” and is, “[a]t
its core . . . a reasonableness test or a rational basis test.” 49 The issue is

45 See TEX. GOV’T CODE § 2001.141(d).

46 Id. §§ 2001.171, .174 (describing the standard of review “if the law does

not define the scope of judicial review”); see TEX. WATER CODE § 5.351
(authorizing judicial review from a TCEQ decision without defining the scope
of judicial review).
47 TEX. GOV’T CODE § 2001.174(2).

48 Dyer v. TCEQ, 646 S.W.3d 498, 505 (Tex. 2022).

49 Ammonite Oil & Gas Corp. v. R.R. Comm’n of Tex., 698 S.W.3d 198, 207

(Tex. 2024) (internal quote marks and citations omitted).

17
“not whether the agency’s decision was correct, but only whether the
record demonstrates some reasonable basis for the agency’s action.” 50 To
prevent courts from “usurping the agency’s adjudicative authority,” 51 an
agency’s findings, inferences, conclusions, and decisions are presumed
to be sufficient unless the protestant proves otherwise. 52
Arbitrariness is a distinct ground for reversal. 53 An agency acts
arbitrarily or abuses its discretion if it fails to consider a mandatory
factor, considers an irrelevant factor, considers appropriate factors but
reaches a completely unreasonable result, or fails to follow its own
regulations. 54 As SOS frames the issues, TCEQ’s decision to grant the
City’s permit application is arbitrary and erroneous as a matter of law
because TCEQ applied the wrong standard and substantial evidence
does not support TCEQ’s decision under the correct standard.
Many of SOS’s arguments seem to attack TCEQ’s water-quality
rules as inconsistent with federal law, 55 but the question presented in

50 Mireles v. Tex. Dep’t of Pub. Safety, 9 S.W.3d 128, 131 (Tex. 1999).

51 N.E. Indep. Sch. Dist. v. Riou, 598 S.W.3d 243, 251 (Tex. 2020) (internal

quote marks and citation omitted).
52 Pub. Util. Comm’n of Tex. v. Tex. Indus. Energy Consumers, 620 S.W.3d

418, 427 (Tex. 2021).
53 Id.

54 City of El Paso v. Pub. Util. Comm’n of Tex., 883 S.W.2d 179, 184 (Tex.

1994); Pub. Util. Comm’n v. Gulf States Utils., 809 S.W.2d 201, 207 (Tex. 1991).
55 Neither party disputes that the EPA has determined that the relevant

Texas standards comport with federal law. See 33 U.S.C. § 1313(a), (c)
(requiring EPA approval and triennial review of state water-quality standards
and implementation procedures for consistency with the Clean Water Act);
40 C.F.R. § 131.12 (setting minimum standards for compliance with federal
law). The validity of that determination is not before us.

18
this state-law suit for judicial review is whether TCEQ followed the
relevant Texas statutes and rules governing its permitting decision. We
therefore ask only whether TCEQ followed its antidegradation rules as
written, and we regard SOS’s arguments only through that lens. That
being so, the main issue turns on the proper construction and
application of the antidegradation standards in 30 Texas Administrative
Code section 307.5 and corresponding implementation procedures. 56
Agency rules are construed under well-established and well-known
statutory construction principles that require enforcement according to
the text’s plain, technical, or defined language. 57
SOS’s secondary issue involves a dispute about the necessity of a
“statement of the underlying facts” in the final agency order. This too
presents a question of law resolved by statutory construction
principles. 58 Our duty in all such matters is to adhere to the
promulgated language “without adding to it or subtracting from it.” 59
B. Tier 1 and Tier 2 Antidegradation Review
The Tier 1 and Tier 2 antidegradation standards differ but
materially overlap. Both expressly require maintenance of existing uses
and water quality sufficient to protect those uses. 60 Subject to an

56 See 2010 IPs, supra note 1.

57 TCEQ v. Maverick County, 642 S.W.3d 537, 544 (Tex. 2022).

58 Id.

59 Id. at 546.

60 30 Tex. Admin. Code 307.5(b); see id. § 307.3(27) (defining “existing
uses”).

19
exception not at issue here, 61 Tier 2 additionally prohibits any discharge
activities that would cause “degradation” of waters that are cleaner than
necessary “to support propagation of indigenous fish, shellfish,
terrestrial life, and recreation in and on the water.” 62 “Degradation” is
defined as “a lowering of water quality by more than a de minimis
extent, but not to the extent that an existing use is impaired.” 63 A
discharge that would impair existing uses flunks both standards. A
discharge that lowers “water quality” more than nominally flunks Tier 2
even if existing uses are not disturbed. 64
SOS argues that the draft permit fails both the Tier 1 and Tier 2
standards. It also argues that TCEQ erroneously “collapsed” the two
inquiries by making fact findings that equate the Tier 1 and Tier 2
standards. The zone of disagreement between the parties has
narrowed—at least for purposes of this appeal—to the authorized

61 The Tier 2 standard allows TCEQ to authorize a discharge of pollutants

that would degrade high-quality waters only if the agency is satisfied that
“lowering of water quality is necessary for important economic or social
development.” See id. § 307.5(b)(2). Although TCEQ’s final order includes
several fact findings related to the City’s “need” for the permit, the City has
never invoked or relied on the exception. Rather, the question before us
concerns the proper standard for determining whether a permitted discharge
would cause degradation as defined in Tier 2, not whether a permit should
issue despite degradation. Accordingly, we do not consider whether either the
findings or the evidentiary record support the exception.
62 Id. (defining “fishable/swimmable waters”).

63 Id.

64 See, e.g., de minimis, BLACK’S LAW DICTIONARY, at 544 (11th ed. 2019);

de minimis, NEW OXFORD AMERICAN DICTIONARY, at 461 (3d ed. 2010).

20
discharge’s predicted impact on a single water-quality parameter:
dissolved oxygen. 65
SOS contends, first, that the draft permit does not satisfy Tier 1
as a matter of law, and therefore also fails Tier 2 as a matter of law,
because one of the City’s two DO models estimated that DO could drop
below Onion Creek’s site-specific 5.0 mg/L criterion to 4.87 mg/L.
However, other modeling, including TCEQ’s own modeling, projected
that a minimum of 5.0 mg/L would be maintained under the worst-case
scenario. Under the applicable standard of review, TCEQ was not
required to accept the lowest of the City’s results over its own modeling
yields. On top of that, all the DO modeling was performed using the
much higher level of discharge the City sought in its initial application
(995,000 gallons/day) rather than the level TCEQ’s final order
authorizes (822,500 gallons/day). The difference in discharge volume
makes TCEQ’s DO projection even more conservative. Because
substantial evidence supports TCEQ’s determination that the
authorized discharge would satisfy Onion Creek’s site-specific DO
criterion and would not disturb existing uses, SOS’s Tier 1 complaint
fails under the applicable standard of review.
SOS presents a more robust assault on TCEQ’s determination
that the permitted discharge would not degrade Onion Creek’s water
quality. The gist of the argument is that Tier 2 must prohibit a
cognizable change in any single component of the water’s chemical

65 Although changes to TP and TN levels figured prominently in the dispute

at the administrative and lower-court levels, no issues specific to nutrient
loading are presented on appeal here.

21
composition because such a construction is (1) preordained by the Clean
Water Act’s “objective . . . to restore and maintain the chemical,
physical, and biological integrity of the Nation’s waters” 66 and
(2) necessary to distinguish Tier 1 from Tier 2. SOS finds confirmation
of such a granular approach in TCEQ’s “Procedures to Implement the
Texas Surface Water Quality Standards” (implementation
procedures), 67 in select cases from other jurisdictions, and in certain
EPA guidance that is external to the record. 68 We do not.
Tier 2’s text is clear: degradation is a “lowering of water quality,”
not a “lowering of water-quality parameters” or “water-quality
components” or “water-quality constituents.” 69 By its plain language,
Tier 2’s focus is on “water quality,” not the DO level or any other
parameter standing alone. Instead of focusing on the effect the DO level
has on Onion Creek’s water quality, the antidegradation analysis SOS

66 33 U.S.C. § 1251(a); see supra notes 5 & 55.

67 See 2010 IPs, supra note 1.

68 See EPA, Water Quality Standards Handbook Chapter 4:
Antidegradation Cover Page (2012) (“The [Handbook] does not impose legally
binding requirements on the EPA, states, tribes or the regulated community,
nor does it confer legal rights or impose legal obligations upon any member of
the public. . . . This document does not constitute a regulation, nor does it
change or substitute for any [Clean Water Act] provision or the EPA
regulations.”); Memorandum from Ephraim S. King, Dir., Office of Sci. and
Tech., to EPA Water Mgmt. Div. Dirs., Regions 1–10 (Aug. 10, 2005) (“shar[ing]
. . . OST’s current recommendation regarding significance thresholds and
lowering of water quality in high quality waters in the context of tier 2
antidegradation reviews” for the purpose of providing “the Regions with
technical recommendations for your consideration as you work with states . . .
and as you review antidegradation implementation methods that adopt
significance thresholds”).
69 See 30 Tex. Admin. Code § 307.5(b)(2).

22
endorses focuses only on the DO parameter itself. The former, not the
latter, is the approach the antidegradation rules prescribe. 70
TCEQ’s implementation procedures also do not support the
methodology SOS favors. As those procedures confirm, water quality is
composed of a complex set of ecological circumstances affected by several
“parameters of concern,” including but not limited to DO. 71 Other
parameters—such as bacteria, phosphorus, nitrogen, turbidity, foam
and froth, temperature, sulfate, chloride, pH, toxic pollutants,
radioactive materials, taste and odor, suspended solids, oil, and grease—
may also be considered in evaluating water-quality impact, along with
“any other constituent that could lower water quality.” 72 And while the
implementation procedures provide methods for individually evaluating
these components, that process is consistent with TCEQ’s whole-body
approach because assessing overall health necessarily begins with an
evaluation of the parts. 73 The implementation procedures leave no
doubt, however, that a parameter change is not the end of the matter.

70 See TCEQ v. Maverick County, 642 S.W.3d 537, 541 (Tex. 2022) (“When

a statute or rule defines its terms, courts should not construct a restated
definition using alternative verbiage that adds or subtracts substantive
requirements or limiting factors.”).
71 2010 IPs, supra note 1, at 61-62; see State Program Requirements:
Approval of Application to Administer the National Pollutant Discharge
Elimination System (NPDES) Program; Texas, 63 Fed. Reg. 51164-01, 51193
(Sept. 24, 1998) (“EPA has not mandated whether States/Tribes apply ‘Tier 2’
on a parameter-by-parameter basis or on a waterbody-by-waterbody approach
as Texas does. . . . The antidegradation review may initially focus on dissolved
oxygen; however, all pollutants are subject to review.”).
72 See 2010 IPs, supra note 1, at 61-62.

73 Id. at 55-69.

23
To the contrary, those procedures substantiate a qualitative whole-body
approach that involves a somewhat subjective evaluation informed by
both numerical and non-numeric information. 74
The qualitative nature of the Tier 2 antidegradation assessment
is best exemplified by the provisions discussing loss of a water body’s
“assimilative capacity.” 75 In SOS’s view, these portions of the
implementation procedures support the conclusion that a reduction in
DO from 6.44 mg/L to 5.0 mg/L is degradation as a matter of law. They
do not. The procedures state:
New discharges that use less than 10% of the existing
assimilative capacity of the water body at the edge of the
mixing zone are usually not considered to constitute
potential degradation as long as the aquatic ecosystem in
the area is not unusually sensitive to the pollutant of

74 See Wood v. TCEQ, No. 13-13-00189-CV, 2015 WL 1089492, at *1, *5-6

(Tex. App.—Corpus Christi–Edinburgh, Mar. 5, 2015, no pet.) (affirming the
TCEQ’s decision to overrule the ALJ’s recommendation because the ALJ
applied an improper standard in requiring quantified evidence when the TCEQ
measures antidegradation under the narrative standard); see also TCEQ v.
City of Waco, 413 S.W.3d 409, 412 n.3 (Tex. 2013) (observing that a
“qualitative” water-quality standard has been described as a “somewhat
subjective assessment of ‘too much,’ in contrast to quantitative measures”).
75 2010 IPs, supra note 1, at 64-66. The term “assimilative capacity” is not
defined in Texas’s water-quality regulations or the Clean Water Act. The IPs
likewise provide no definition. EPA’s online dictionary of environmental terms
defines “assimilative capacity” as “[t]he ability of a natural body of water to
receive wastewaters or toxic materials without harmful effects and without
damage to aquatic life.” EPA, Terms & Acronyms, https://sor.epa.gov/sor_
internet/registrytermreg/searchandretrieve/termsandacronyms/search.do
(last visited Apr. 3, 2025). A 2005 internal memo from the EPA’s Office of
Science and Technology, which SOS attached to its merits brief, defines the
term as referring to “the difference between the applicable water-quality
criterion for a pollutant parameter and the ambient water quality for that
pollutant parameter where it is better than the criterion.” Memorandum from
Ephraim S. King, supra note 68.

24
concern. New discharges that use 10% or greater of the
existing assimilative capacity are not automatically
presumed to constitute potential degradation but will
receive further evaluation. 76
Importantly, although DO has numeric criteria, which would make it
amenable to assimilative-capacity screening, the implementation
procedures expressly state that “[t]his screening procedure is not
applicable to dissolved oxygen.” 77 More importantly, the
implementation procedures are express in not considering such changes
to individual parameters as establishing degradation but rather as
requiring “further evaluation.” 78 The numbers are what the numbers
are, so any “further evaluation” means assessing such parameters in
connection with other considerations affecting water quality.
What SOS seems to find most compelling on this topic is a
provision in the procedures providing the following as one of the
“[e]xamples where degradation is likely to occur”:
Increased loading of oxygen-demanding substances
that is projected to decrease dissolved oxygen by more than
0.5 mg/L for a substantial distance in a water body that has
exceptional quality aquatic life and a relatively unique and
potentially sensitive community of aquatic organisms. 79
In SOS’s estimation, this provision proves not only that degradation of
water quality is determined on a parameter-by-parameter basis but also
that if a 0.5 mg/L projected decrease in DO is “likely” degradation, then

76 2010 IPs, supra note 1, at 64 (emphasis added).

77 Id.

78 Id.

79 Id. at 66 (bolding in original).

25
a 1.44 mg/L projected decrease, like the one anticipated for Onion Creek,
certainly is.
There are several flaws in SOS’s extrapolated conclusion. First,
the cited example refers to water that has “exceptional quality aquatic
life” and a “relatively unique and potentially sensitive community of
aquatic organisms,” which Onion Creek does not. 80 Second, it applies
when a 0.5 mg/L decrease is projected “for a substantial distance in a
water body,” not just at the discharge point. Third, and most
importantly, the IPs expressly state that even under these
circumstances, such a change in exceptional waters is only an indicator
of potential degradation that requires further evaluation:
The following examples are intended to provide general
guidelines as to when degradation becomes likely. The
examples do not define degradation, nor do they address all
pollutants and situations that can cause degradation.
Final determinations are case-specific and can depend on
the characteristics of the water body and local aquatic
communities. Lower increases in loading may constitute
degradation in some circumstances, and higher loadings
may not constitute degradation in other situations. 81
Consistent with the water-quality standards, the implementation
procedures describe a qualitative assessment of degradation based on

80 30 Tex. Admin. Code §§ 307.7(b)(3)(A) (Table 3) (describing waters with

“exceptional aquatic life use” as having “exceptional or unusual” species
assemblage, a habitat of “outstanding natural variability,” and “exceptionally
high” species richness and diversity while those waters with “high aquatic life
use” have species assemblages of the “usual association of regionally expected
species,” a “highly diverse” habitat, and “high” species richness and diversity),
.10(1) (App’x A) (Segment No. 1427, Onion Creek) (designating Onion Creek
for high aquatic life use).
81 2010 IPs, see supra note 1, at 66 (emphases added).

26
overall water quality, rather than a granulated
parameter-by-parameter approach. TCEQ perhaps could have adopted
rules and standards implementing a parameter-by-parameter approach,
but it did not. Instead, the antidegradation assessment allows TCEQ to
make an informed judgment call as to whether any changes in the water
body’s chemistry lower water quality by more than a de minimis
extent. 82 SOS may be uncomfortable with the latitude and discretion
such an approach affords state regulators, but both the rules and the
implementation procedures not only allow, but contemplate, a
qualitative assessment on a whole-water basis. 83
In support of SOS, some amici point to section 307.5(c)(2)(B) of
the antidegradation rules as calling for a parameter-specific
antidegradation review. That subsection, which discusses “[g]eneral
provisions for implementing the antidegradation policy,” says: “For
dissolved oxygen, analyses of degradation under Tier 2 must utilize the
same critical conditions as are used to protect instream criteria. For
other parameters, appropriate conditions may vary.” 84 But this only

82 See supra note 74.

83 We need not assess the extent to which any legal weight or binding force

can be assigned to the implementation procedures, because even assuming
those procedures have some force of law, SOS’s interpretation of them fails on
its own terms.
84 30 Tex. Admin. Code § 307.5(c)(2)(B).
Joint amicus briefs supporting
SOS were submitted by Friends of the Brazos River, Bayou City Waterkeeper,
Coastal Watch Association, Environmental Stewardship, Friends of Hondo
Canyon, Greater Edwards Aquifer Alliance, Port Aransas Conservancy, Texas
Conservation Alliance, the Watershed Association, Ingleside on the Bay
Coastal Watch Association, Hillcrest Residents Association, Protect Our

27
proves the point. The antidegradation policy recognizes that water
quality is composed of a variety of parameters and that an
antidegradation review necessarily starts by analyzing parameters of
concern individually. Yet the Tier 2 standard is couched in terms of the
whole, not the individual parameters. This is not to say that changes in
a single parameter could never be significant enough to lower water
quality, but the ultimate determination is TCEQ’s to make based on an
evaluation of the water’s post-discharge quality.
SOS invokes the Clean Water Act’s “objective” and “goals” and a
couple of EPA guidance documents as supporting a contrary
construction. 85 But SOS points to nothing that commands a
parameter-based application of the Tier 2 standard. 86 Even assuming
any of those things could be read in the way SOS suggests, none override

Blanco, and Granbury Fresh. The Homebuilders Association of Greater Austin
submitted an amicus brief supporting TCEQ and the City.
85 33 U.S.C. § 1251 (Congressional declaration of goals and policy).

86 The EPA has itself confirmed that “policies and guidance are not legal

requirements,” so TCEQ “is not bound to follow them exactly.” State Program
Requirements, supra note 71, at 51181. The EPA has more explicitly stated
that “[a]lthough for the sake of national consistency EPA strongly encourages
States implementing an NPDES program to do so in accordance with EPA
policies and guidance, there is nothing in either the [Clean Water Act] or
[EPA’s regulations] that requires them to do so. Therefore, [TCEQ]’s
statement in [its memorandum of agreement with EPA] that it will utilize
EPA’s policies and guidance only to the extent they do not conflict with Texas
law or policy or [TCEQ] guidance is not in conflict with the requirements for
NPDES authorization.” Id.

28
what the Texas rules say. SOS also struggles to find supporting
authority in the jurisprudence. The few cases it offers are not on point. 87
Finally, SOS’s complaint that TCEQ improperly “collapsed” the
Tier 1 and Tier 2 standards is mistaken. SOS contends the final order
focused only on whether the permit would protect existing uses, not on
the distinct question of whether the permit would lower water quality
in Onion Creek. By way of example, SOS points to Finding of Fact
(FOF) 90, which states: “A Tier 2 review confirmed that no significant
degradation of water quality is expected in Onion Creek, which has been
identified as having high aquatic life uses, such that the existing uses
will be maintained and protected.” While TCEQ’s Tier 2 findings refer
to both degradation and existing uses, those are the words the standard
employs. As the court of appeals observed, the “substantial overlap” in
the Tier 1 and Tier 2 standards “mak[es] it difficult to analyze the two
standards separately.” 88

87 See generally County of Maui v. Haw. Wildlife Fund, 590 U.S. 165, 169

(2020) (rejecting claim that groundwater discharge was exempt from state
permitting altogether because it discharged from a point source into navigable
waters); Arkansas v. Oklahoma, 503 U.S. 91, 94-95 (1992) (involving a dispute
about interstate water pollution); Ky. Waterways All. v. Johnson, 540 F.3d 466,
482-83 (6th Cir. 2008) (challenge to EPA approval of state antidegradation
rules seeking to categorically exempt six types of pollution discharges from
Tier 2 review); Greater Yellowstone Coal. v. U.S. EPA, No. 4:12-CV-60-BLW,
2013 WL 1760286, at *2 (D. Idaho Apr. 24, 2013) (challenge to EPA approval
of state antidegradation rules enacting “an automatic exemption from Tier II
antidegradation review if the additional pollution from a new activity would
consume only 10% or less of the ‘assimilative capacity’ of a water body”
(emphasis added)).
88 668 S.W.3d 710, 736 (Tex. App.—El Paso 2022).

29
Other fact findings confirm TCEQ’s understanding and
maintenance of the distinction, including FOF 78—“An antidegradation
review ensures that a proposed discharge does not impair the uses or
degrade the water quality of the receiving waters”—and FOF 88, which
states: “The antidegradation requirements have been satisfied because
(a) DO will be maintained at concentrations that support a healthy
aquatic life community; [and] (b) a phosphorous limit has been imposed
to assure that the proposed discharge will protect and maintain the
water quality of water bodies that exceed fishable/swimmable
quality . . . .” Besides that, the final order and evidence in the record
more than adequately demonstrate that TCEQ applied the correct
standard in conducting a Tier 2 review that evaluated both the impact
on existing uses and the potential for degradation. 89 To the extent SOS
faults the order for failing to use the definitional “no more than a de
minimis extent” language in its findings, it was not required to do so.
Tier 2’s governing standard is “degradation” of “water quality.” The
findings and conclusions in the final order comport with what the rule
requires.
C. Compliance with APA Section 2001.141
We turn now to SOS’s argument that TCEQ’s final order is invalid
because it lacks a statement of “underlying facts” to support several
“ultimate” fact findings and conclusions of law. 90 APA section 2001.141

89 See id. at 735.

90 See W. Tex. Utils. Co. v. Off. of Pub. Util. Couns., 896 S.W.2d 261, 270

(Tex. App.—Austin 1995, no writ) (“An agency’s findings of fact fall into two
categories: findings of basic fact and findings of ultimate fact. A finding of

30
requires a final agency order to include separately stated findings of fact
and conclusions of law. 91 In addition, any fact finding “set forth in
statutory language” must be accompanied by “a concise and explicit
statement of the underlying facts supporting the finding.” 92 Such
findings need not take any particular form, 93 but “[p]roper underlying
(basic) findings of fact” should be (1) “stated as the agency’s findings”
rather than as recitals of evidence or summaries of testimony and
(2) “clear, specific, non-conclusory, and supportive of the ultimate
statutory findings.” 94 A statement of underlying fact findings must
generally enable a reviewing court to “fairly and reasonably” say that
the basic facts “support the statutorily required criteria.” 95
In addition to incorporating the ED’s extensive responses to
public comments, the final order includes more than two dozen fact
findings devoted to addressing TCEQ’s antidegradation review and

ultimate fact is reached by inference from basic facts.”); see also BFI Waste Sys.
of N. Am., Inc. v. Martinez Env’t Grp., 93 S.W.3d 570, 578 n.8 (Tex. App.—
Austin 2002, pet. denied) (“The ultimate facts disputed during a contested case
hearing do not always require detailed findings of underlying facts.”).
91 TEX. GOV’T CODE § 2001.141(b).

92 Id. § 2001.141(d).

93 Tex. Health Facilities Comm’n v. Charter Med.-Dall., Inc., 665 S.W.2d

446, 452 (Tex. 1984) (“This Court has neither the right nor the authority to lay
out a precise form of findings to be made by the Commission.”); accord Tex.
Health Facilities Comm’n v. Presbyterian Hosp. N., 690 S.W.2d 564, 565-67
(Tex. 1985) (an agency order denying a “certificate of need” could not stand
because the underlying fact findings were “mere recitals of evidence,”
conclusory, or did not support the ultimate fact findings).
94 Charter Med.-Dall., 665 S.W.2d at 452.

95 Id. at 451.

31
compliance with applicable water-quality standards. Among them are
various findings to the effect that (1) the ED performed the Tier 1 and
Tier 2 antidegradation review in accordance with the applicable
standards; (2) DO limits in the draft permit will protect Onion Creek’s
existing uses; (3) antidegradation requirements have been satisfied
because “DO will be maintained at concentrations that support a
healthy aquatic life community”; (4) Tier 2 review confirmed no
significant degradation of water quality is expected; (5) Tier 2 review
confirmed that existing uses will be maintained and protected; and
(6) “[t]he proposed discharge will comply with the applicable
antidegradation requirements.” The ED’s response to public comments
further explains TCEQ’s Tier 2 review and the ED’s determination that
“no lowering of water quality by greater than a de minimis amount is
expected.” SOS faults these findings, and the final order itself, for
failing to elaborate more specifically about how the projected drop in DO
concentrations and accompanying loss of assimilative capacity complies
with Tier 1 and does not, consonant with Tier 2’s degradation definition,
constitute “a lowering of water quality by no more than a de minimis
amount.” 96 Although SOS contends the absence of a more particular

96 According to SOS, the “minimally required findings of fact” for
application of the Tier 2 antidegradation rule “include: (1) pre-discharge
‘baseline’ water quality of Onion Creek for both DO and the key nutrient
pollutants, nitrogen and phosphorus; (2) post-discharge levels of these water
quality parameters; (3) a comparison of the post-discharge levels over the
baselines to determine how pollutant levels in the receiving waters were
increased and water quality ‘lowered’; and (4) a determination of whether this
‘lowering’ of water quality was more than de minimis and thus compliant with
the controlling EPA rule.”

32
explanation is fatal to the permit’s issuance, this attack on the final
order falls short for both procedural and substantive reasons.
First, SOS did not preserve the complaint for judicial review.
SOS’s motion for rehearing in the administrative proceeding did not
assert that the agency had omitted the particular findings it now
contends were required to support the final order. The motion’s
sprinkling of generalized complaints about the absence of “underlying
fact findings” is insufficient in itself but even more so because those
complaints were not linked to the specific fact findings assailed on
appeal. 97 To preserve a complaint for judicial review, any
noncompliance with the APA’s fact-finding requirements must first be
raised in the administrative proceeding “with the requisite degree of
specificity.” 98 Failure to present such an objection with at least the
specificity the complaining party contends the agency was obligated to
provide deprives the agency of “an opportunity to discover and correct
the error, if any, or articulate a justification for its action.” 99

97 Hooks v. Tex. Dep’t of Water Res., 645 S.W.2d 874, 880 (Tex. App.—Austin

1983, writ ref’d n.r.e.) (general complaints directed to findings the agency
omitted were not stated with sufficient particularity to preserve them for
judicial review). Although SOS’s briefing here identifies the “minimally
required findings of fact” with particularity, see supra note 96, the rehearing
motion does not.
98 Hooks, 645 S.W.2d at 879.

99 Id. at 879-80 (omitted fact findings must be designated with
particularity); see BFI Waste Sys. of N. Am., Inc. v. Martinez, 93 S.W.3d 570,
578-79 (Tex. App.—Austin 2002, pet. denied) (applicant failed to preserve
complaint about omitted findings of fact and conclusions of law by failing to
sufficiently identify the alleged omission in its motion for rehearing before the
agency).

33
Second, underlying fact findings are not required because TCEQ’s
findings of fact are not set out in “statutory language.” 100 The regulatory
language contained in TCEQ’s antidegradation rules is not statutory
language for which underlying findings are required. 101 In arguing
otherwise, SOS erroneously describes section 26.027 of the Water Code
as establishing mandatory criteria that TCEQ must consider in
conducting an antidegradation review. It plainly does not.
A statement of supportive facts is required “only when the
ultimate fact finding embodies a mandatory fact finding set forth in the
relevant enabling act” or when it “represent[s] the criteria the
legislature has directed the agency to consider in performing its
function.” 102 Section 26.027 broadly authorizes TCEQ to “refuse to issue
a permit when the commission finds that issuance of the permit would
violate the provisions of any state or federal law or rule or regulation
promulgated thereunder[.]” 103 As is immediately apparent, section
26.027 generally allows TCEQ to deny a permit that is contrary to any
rule or law, but it neither states nor directs TCEQ to consider any

100 See TEX. GOV’T CODE § 2001.141(d); Charter Med.-Dall., 665 S.W.2d at

451 (“By limiting the fact-finding requirement to findings ‘set forth in statutory
language,’ the legislature has expressed its intention in this matter.”).
101 TCEQ v. Maverick County, No. 03-17-00785-CV, 2022 WL 2960797, at

*6 (Tex. App.—Austin July 27, 2022, no pet.).
102 Charter Med.-Dall., 665 S.W.2d at 451; see W. Tex. Utils. Co. v. Off. of

Pub. Util. Couns., 896 S.W.2d 261, 270 (Tex. App.—Austin 1995, no writ) (“An
agency’s finding of ultimate fact that does not embody a mandatory fact finding
set forth in the relevant enabling act need not be supported by findings of basic
fact, regardless of how conclusory the finding of ultimate fact may be.”).
103 TEX. WATER CODE § 26.027.

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criteria in granting a permit nor mandates any fact findings at all.
Section 26.027’s language is nowhere close to the type of mandated
criteria or findings that invoke the APA’s “statement of underlying
facts” requirement.
Our leading case on the matter illustrates the difference. In
Texas Health Facilities Commission v. Charter Medical-Dallas, Inc., the
Legislature directed the agency to establish criteria for determining
whether to grant a certificate of need for a proposed project. 104 In doing
so, the Legislature specifically identified five criteria that “the
commission must include” in its rules for making that determination. 105
We held that those mandated criteria, subsequently promulgated in the
agency’s rules, are the type of factors that fall within the scope of fact
findings that must be accompanied by a statement of underlying facts. 106
In contrast, the Legislature’s requirement that the agency consider six
additional factors in developing additional criteria did not. 107 Although
the agency also adopted those factors among its general criteria for
reviewing certificate-of-need requests, the Legislature had not required
it to do so. 108 For permissible waste discharges, section 26.027 of the
Water Code does not mandate any specific findings, criteria, or factors

104Charter Med.-Dall., 665 S.W.2d at 449 (citing subsection 3.10(a) of
former TEX. REV. CIV. STAT. art. 4418h).
105 Id. (citing subsection 3.10(b) of former art. 4418h).

106 Id. at 451 & n.2.

107 Id. at 449-50 & nn.1-2 (comparing the mandatory criteria prescribed in

subsection 3.10(b) of former art. 4418h with the nonmandatory factors
delineated in subsection 3.10(c)).
108 Id. (citing subsection 3.10(c) of former art. 4418h).

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for issuing a discharge permit. 109 It certainly does not require the agency
to make negative findings on the full panoply of laws and regulations
that permit issuance would not offend.
To construe the statute as SOS wishes would result in an absurd
extension of the APA’s language that would infect every TCEQ order
with potentially nullifying error for failing to identify and provide
underlying findings of fact that a permit’s issuance complies with every
federal and state law, rule, and regulation. Such a burden would be
impossibly onerous and an unreasonable construction and application of
the APA. 110 Accordingly, we must and do reject it.
SOS once again leans heavily on the Clean Water Act’s “objective”
and “goals” of “maintaining the chemical, physical, and biological
integrity of the Nation’s waters,” 111 but it points to no statute that would
require TCEQ to elaborate on what “de minimis” means or to explain
why a predicted drop in a single water-quality parameter would not

109 Compare TEX. WATER CODE § 26.027(a) with, e.g., TEX. UTIL. CODE
§ 37.056(a), (c) (specifying required findings and criteria for granting or
denying a certificate of convenience and necessity).
110 Imposing such a burden on the agency is also contrary to the
burden-shifting scheme in section 2003.47(i-1)–(i-3) of the Government Code.
When the administrative record is filed, that statute recognizes a presumption
that “the draft permit meets all state and federal legal requirements.” TEX.
GOV’T CODE § 2003.47(i-1). To rebut the presumption, the protestant must
present evidence that “the draft permit violate[s] a specifically applicable state
or federal requirement.” Id. § 2003.47(i-2). Section 2003.47 negates any
reading of section 26.027 as imposing an obligation on TCEQ to provide
compliance findings when the protestant has not presented evidence that the
permit violates a legal requirement that is “specifically applicable.” As TCEQ
explains, the factfinders (the ALJ and TCEQ) are “not starting with a factual
void to fill.”
111 33 U.S.C. § 1251(a).

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lower water quality by more than a de minimis extent. As we have
explained above, the Tier 2 antidegradation standard relates to
sustaining overall water quality, not maintaining individual parameter
levels. Because the governing statutes do not require TCEQ to make
findings for individual water-quality parameters in a Tier 2 review, no
additional findings were required. The final order separately states
TCEQ’s findings of fact and conclusions of law and sufficiently informs
the parties of the basis for its antidegradation decision. No additional
findings or statements were required to comply with section 2001.141.
III. Conclusion
In granting the City of Dripping Springs’s wastewater discharge
permit application, TCEQ did not violate either section 2001.141 or the
antidegradation rules and implementation procedures. We therefore
affirm the court of appeals’ judgment upholding the permit’s issuance.

John P. Devine
Justice

OPINION DELIVERED: April 11, 2025

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