OPINION
The City of Celina and the Texas Commission on Environmental Quality (“TCEQ”) challenge the trial court’s denial of portions of their pleas to the jurisdiction. Appellants contend that the trial court lacks jurisdiction over Dynavest Joint Venture’s petition for a declaratory judgment because the petition is an impermissible collateral attack based on a statute that does not apply to the TCEQ’s action. We affirm the challenged portions of the district court’s order.
The City of Celina filed an application with the TCEQ on September 2, 2003, seeking amendment of its certificate of convenience and necessity to expand the area in which the City could supply water. On January 5, 2006, the TCEQ granted the application. The expanded service area encompasses land outside the City’s extraterritorial jurisdiction, including Dyna-vest’s property.
On December 6, 2006, Dynavest filed this suit 1 seeking a declaratory judgment that the amended certificate is void. 2 Dy-navest relies on the version of Texas Water Code section 13.2451(b) enacted by the legislature in 2005:
The commission may not extend a municipality’s certificate of public convenience and necessity beyond its extraterritorial jurisdiction without the written consent of the landowner who owns the property in which the certificate is to be extended. The portion of any certificate of public convenience and necessity that extends beyond the extraterritorial jurisdiction of the municipality without the consent of the landowner is void.
Act of May 29, 2005, 79th Leg., R.S., ch. 1145, § 5, sec. 13.2451(b), 2005 Tex. Gen. Laws 3771, 3773 (“2005 version”) (amended 2007) (current version at Tex. Water Code Ann. § 13.2451(b) (West Supp.2007)). Dynavest argues that, because it did not consent to the amendment’s extension of the scope of the City’s certificate to include Dynavest’s property outside the Celina city limits, the portion of the amendment so extending the certificate is void. Dyna-vest’s theory of voidness is premised on the applicability of the 2005 version of Texas Water Code section 13.2451(b) containing the consent requirement. 3
*402 Appellants filed pleas to the jurisdiction. The TCEQ argued that Dynavest’s citation to the declaratory judgment act did not alter the fact that this petition was actually an untimely challenge to and an impermissible collateral attack on the certificate. The TCEQ also argued that Dynavest’s theory that the amended certificate is void was based on an inapplicable statute and, therefore, could not vest the trial court with jurisdiction over an otherwise impermissible collateral attack. The City similarly contended that the declaratory judgment act did not support a remedy redundant of those designed to permit challenge to agency orders.
In its order denying the plea to the jurisdiction concerning the declaratory judgment action, the trial court found that it has jurisdiction under the Uniform Declaratory Judgment Act (UDJA) to interpret and construe Texas Water Code section 13.2451 and to determine if the amended certificate is void. In a letter to the parties, the trial court explained that it has jurisdiction because Dynavest stated a claim that could lead to a judgment that the order is void. The trial court declined to examine the statute further — i.e., to determine whether the statute applies — because “[t]o examine the statute further would go to the merits of the claim.” Appellants filed notices of interlocutory appeal challenging the denial of their pleas to the jurisdiction.
A court’s subject-matter jurisdiction traditionally consists of the power, conferred by constitutional or statutory provision, to decide the kind of claim alleged in the plaintiffs petition and to grant relief.
Sierra Club v. Texas Natural Res. Conservation Comm’n,
Courts review the denial of a plea to the jurisdiction de novo because whether a court has subject matter jurisdiction is a question of law.
Texas Natural Res. Conservation Comm’n v. IT-Davy,
The City argues that the trial court lacks jurisdiction because the UDJA does not confer jurisdiction to consider a challenge to an agency ruling when anoth
*403
er statute authorizes review of that ruling.
See Beacon Nat’l Ins. Co. v. Montemayor,
Although courts generally do not have jurisdiction to consider collateral attacks on state agency decisions, a collateral attack upon an agency order may be maintained successfully if the order is void.
Chocolate Bayou Water Co. & Sand Supply v. Texas Natural Res. Conservation Comm’n,
Appellants contend that the trial court should have determined whether the 2005 version of water code section 13.2451(b) applies to the City’s application for an amended certificate when it assessed the plea to the jurisdiction. In its letter to the parties, the trial court declined to make that determination on grounds that the applicability was a merits determination not appropriate for resolution on a plea to the jurisdiction.
Although trial courts may inquire into jurisdictional issues that overlap with or implicate merits issues, we are not persuaded that appellants’ pleas to the jurisdiction required the trial court to decide whether the 2005 version of the statute applies in order to assess its jurisdiction over Dynavest’s petition. Dynavest requests a declaration that the TCEQ’s order amending the City’s certificate is void. The district court has general jurisdiction over all remedies except where jurisdiction is conferred on another entity, and is presumed to have jurisdiction absent a contrary showing.
See Sweeney v. Jefferson,
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Courts that have decided merits-related issues, including statutory interpretation, have done so because it was necessary to resolve the issue in order to resolve the question of the court’s jurisdiction.
See generally Hendee,
In its reply brief, the TCEQ asserts that a 2007 amendment to section 13.2451(b) has “nullified” Dynavest’s cause of action.
See
Act of May 28, 2007, 80th Leg., R.S., ch. 1430, § 2.08, sec. 13.2451(b), 2007 Tex. Gen. Laws 5848, 5866. This argument was not part of the proceedings below and, therefore, we cannot consider it in this interlocutory appeal.
See Austin Indep. Sch. Dist. v. Lowery,
The trial court did not err by refusing to decide whether the 2005 version of water code section 13.2451(b) applies when it evaluated appellants’ pleas to the jurisdiction. The trial court has jurisdiction over collateral attacks seeking a declaration that a challenged agency action is void.
See Chocolate Bayou,
We affirm the portions of the trial court’s order denying the aspects of appellants’ pleas to the jurisdiction at issue in this interlocutory appeal.
Affirmed.
Notes
. This is not a suit for judicial review of a ruling, order, or decision. Dynavest filed a previous suit in May 2006 seeking judicial review of the TCEQ order. A party may seek judicial review of a TCEQ ruling, order, or decision by filing a petition not more than thirty days after the effective date of the challenged ruling, order, or decision. Tex. Water Code Ann. § 5.351 (West 2000). That suit, filed four months after the TCEQ’s order, was dismissed as untimely.
. Dynavest also sought a declaration that the TCEQ’s order violated its own rules or was an invalid ad hoc rule. The district court held that it lacked jurisdiction over that request. Dynavest has not filed an interlocutory appeal from that decision.
.Dynavest stated in its motion for summary judgment — part of the record on appeal, although no ruling on that motion is before us — that ‘‘[t]his case turns on the effective date of Texas Water Code Section 13.2451(b).” Although Dynavest argues that the TCEQ is barred by regulation from expanding service areas outside a ciiy’s extraterritorial jurisdiction absent landowner consent, see 30 Tex. Admin. Code § 291.105(c)(2) (2007) (Tex. Comm’n on Envtl. Quality, Contents of Certificate of Convenience and Necessity Application); 30 Tex. Reg. 8958, 8961 (2005), the regulation does not declare a certificate issued without landowner consent void. Dynavest does not contend that the *402 regulation applies to render the certificate void.
