delivered the opinion of the Court.
Super Wash, Inc., a car wash business, is seeking to estop the City of White Settlement from enforcing an ordinance that requires Super Wash to maintain a continuous fence along one side of its property. On competing motions, the trial court granted summary judgment for the City. The court of appeals reversed and remanded, holding that issues of material fact precluded summary judgment. We conclude that, under the circumstances pre *772 sented, the City cannot be estopped from enforcing its zoning ordinance. We reverse the court of appeals’ judgment in part and render judgment for the City.
I
Background
Super Wash’s property was originally zoned for multi-family housing but was rezoned in 1986 for commercial use. Prior to that rezoning, area residents encouraged the City to impose restrictions on the commercial use to minimize vehicular traffic in their neighborhood. The City’s ordinance contained language designed to meet those concerns:
This change of zoning is expressly conditioned upon the owner and/or occupant, now or later, of this property constructing and thereafter maintaining a six-foot wooden privacy fence with brick columns on Longfield [Drive]. 1
City of White Settlement, Tex., Ordinance No. 837-86 (March 25, 1986) (the Ordinance). The Ordinance also contained a reversionary clause providing that, if the owner or occupant did not erect and maintain the fence, the property would revert to multi-family housing use. Id
Super Wash was not aware of the Ordinance when it purchased the property in August 2000. At the start of construction, Super Wash submitted its site plan to the City for approval. The plan called for a curb cut and exit onto Longfield Drive and did not provide for a privacy fence separating the car wash from the neighborhood. Because the City’s zoning map omitted any reference to the fence requirement, a City building official mistakenly approved Super Wash’s site plan and issued a building permit on February 8, 2001. Within a week of the permit’s issuance, residents in the abutting neighborhood brought the Ordinance to the City’s attention and insisted that the car wash comply with it. On February 12, 2001, the City informed Super Wash that it was required to build a fence along Longfield Drive. On March 1, after construction was forty-five percent complete, the City informed Super Wash that it must also remove the planned exit onto Longfield Drive in accordance with the City’s interpretation that the Ordinance required a continuous fence. Super Wash amended its site plan and, under protest, completed construction in line with the City’s interpretation.
Super Wash sued the City, claiming that the Ordinance: (1) was not uniformly applied to all commercially zoned property, (2) constituted impermissible contract zoning, 2 and (3) included a rever-sionary clause that impermissibly delegated the City’s legislative power. Super Wash argued alternatively that the City should be estopped from enforcing the Ordinance. Both parties moved for summary judgment. The trial court granted the City’s motion and denied Super Wash’s motion. With attorney’s fees the only remaining issue, the parties filed a joint motion for final judgment, which was granted.
Super Wash appealed, and the court of appeals affirmed the trial court on the uniformity and contract zoning issues. 131 *773 S.W.3d 249, 257-59. Super Wash has not contested those holdings. The court reversed and rendered judgment that the reversionary clause was void and severa-ble. Id. at 260-61. The City does not contest that holding. As to the estoppel issue, the court held there were issues of material fact regarding whether the City official’s acts were authorized, whether this was the type of case that required estop-pel, and whether the City would be prevented from exercising its governmental functions if it were estopped from enforcing the Ordinance. Id. Accordingly, the court of appeals reversed the trial court’s judgment and remanded the case for trial. Id. at 261. We granted the City’s petition for review to determine whether the court of appeals erred in remanding the estoppel issue. 48 Tex. Sup.Ct. J. 454 (Mar. 14, 2005).
II
Discussion
We have long held that a city cannot be estopped from exercising its governmental functions,
3
but have not thoroughly presented the reasons for that settled rule.
See City of Hutchins v. Prasifka,
Decisions from the U.S. Supreme Court elaborate on these themes, and we find it useful to mention a few here. This line of cases makes clear that “equitable estoppel will not lie against the Government as against private litigants.”
Office of Personnel Mgmt. v. Richmond,
estoppel helps preserve separation of powers; legislative prerogative would be undermined if a government agent could— through mistake, neglect, or an intentional act — effectively repeal a law by ignoring, misrepresenting, or misinterpreting a duly enacted statute or regulation.
See Richmond,
Not unlike the U.S. Supreme Court, we have held that the unauthorized act of a government official cannot estop a city’s enforcement of a zoning ordinance.
See Prasifka,
However, we also found “authority for the proposition that a municipality may be estopped in those cases where justice requires its application, and there is no interference with the exercise of its governmental functions.”
A
Estoppel When “Justice Requires”
Super Wash argues that the exception articulated in
Prasifka
should apply here, as this is a case in which justice requires estoppel. We have applied the exception in only one circumstance. In
Roberts v. Haltom City,
we held that a city could be estopped from enforcing a law that required a party bringing suit against the city to file a notice of claim within thirty days of injury.
Roberts,
Roberts
and
Schautteet
illustrate the types of cases that may fall under the “justice requires” exception. In both, there was evidence that city officials may have affirmatively misled the parties seeking to estop the city and that the misleading statements resulted in the permanent loss of their claims against the cities. Evidence that city officials acted deliberately to induce a party to act in a way that benefitted the city but prejudiced the party weighs in favor of applying the exception articulated in
Prasifka. See, e.g., City of Austin v. Garza,
We are not persuaded that this is an exceptional case in which justice requires estoppel. Super Wash is seeking to estop the city from enforcing the fence requirement so that it can build a second entrance/exit to assist with traffic flow. The business has been operating for years without this second entrance/exit, and there is nothing in the record to indicate that it is necessary for its continued operation. This case is unlike
Roberts
or
Schautteet,
in which the party seeking to estop the city would have been
completely
denied relief had estoppel not applied.
See Roberts,
Moreover, while it is true the City issued the building permit in error, the Ordinance was a matter of public record and discoverable by Super Wash before it purchased the lot.
See Davis v. City of Abilene,
Finally, while Super Wash argues that the City should be estopped because it benefitted from adding a commercial business to its tax base due to the erroneously issued building permit, this benefit is simply too attenuated to establish grounds for equitable relief. This case is unlike Garza, *776 in which the city received a large, direct donation of land in exchange for land that was subject to an erroneous plat note. Garza, 124 S.W.3d at 874. There, the court held it would be inequitable to allow a city to retain the benefit of donated land while denying the other party the right to enforce the note, upon which he relied in making the exchange. Id. at 875. In this case, however, there is no evidence that the city received any direct benefit from Super Wash in exchange for the erroneously issued permit;
Therefore, Super Wash does not present an exceptional case in which justice requires estoppel.
B
Interference with Governmental Functions
As we noted in
Prasifka,
even if justice requires estoppel, a city will not be estopped if doing so would interfere with its ability to perform its governmental functions.
This is our first opportunity to clarify what it means to “interfere” with a governmental function. We first note that precluding a city from performing a specific governmental function in a single instance is not per se interference with its governmental functions. Otherwise, every attempt to estop a city would be considered interference with a governmental function, and the exception stated in Pra-sifka could never apply. Rather, in determining whether a case presents an appropriate instance in which to apply the exception, the relevant inquiry is whether estopping the city in a single instance will bar the future performance of that governmental function or impede the city’s ability to perform its other governmental functions.
In conducting this inquiry, the court should first determine what municipal governmental functions, if any, would be affected by estopping the city. We define “governmental functions” generally as those that “are public in nature and performed by the municipality ‘as the agent of the State in furtherance of general law for the interest of the public at large.’”
Gates v. City of Dallas,
More specifically, in the context of estopping a city’s enforcement of a duly enacted ordinance, the court should consider whether estoppel will affect public safety, bar future enforcement of the ordinance, or otherwise impede the city’s ability to serve the general public. A city should not be estopped if doing so would hinder its ability to ensure public safety.
Cf, City of Fredericksburg v. Bopp,
In this case, the court of appeals held that fact issues exist concerning whether the City’s ability to perform its governmental functions would be impaired if it was estopped from barring the Long-field Drive exit.
Ill
Conclusion
We hold that the court of appeals erred in reversing and remanding on the estop-pel question. We reverse its judgment in part and render judgment for the City. Tex. R. App. P. 60.2(c).
Notes
. Longfield Drive separates the commercial property from the residential neighborhood.
. "Contract zoning" occurs when a governmental entity, such as a city, enters into a binding contract in which it promises to zone land in a certain way in exchange for a landowner's promise to use the land in a particular manner.
. The same does not hold true, however, when a city is performing its proprietary functions.
See Gates v. City of Dallas,
. Determining whether a function is governmental in nature is critical under the Tort Claims Act, because the Act only applies when a city is acting in its governmental capacity; the Act does not apply when a city acts in its proprietary capacity. See Tex. Civ. Prac. & Rem. Code §§ 101.0215(a)-(b); see also Tex. Const. art 11, § 13 (providing that the Legislature may define municipal functions as either governmental or proprietary as well as reclassify a function already assigned a certain classification under prior statute or common law).
. The Act’s general definition of “governmental function” is very similar to the common law definition: "those functions that are enjoined on a municipality by law and are given it by the state as part of the state's sovereignty, to be exercised by the municipality in the interest of the general public.” Tex. Civ. Prac.
*777
& Rem. Code § 101.0215(a). Thus, the main effect of the 1987 amendment was to classify some functions as governmental that courts previously deemed proprietary.
Mitchell v. City of Dallas,
. The list includes “street construction and design,” "regulation of traffic,” and "zoning, planning, and plat approval.” Tex Crv. Prac. & Rem. Code §§ 101.0215(a)(3), (a)(21), (a)(29).
. For example, while we did not reach this issue in
Roberts
and
Schautteet
— the only cases in which we have applied the exception articulated in
Prasifka
— there is no indication that estopping the enforcement of a notice of claim requirement (the ordinance at issue in those cases) in a single instance affects a city’s ability to perform its other government functions or precludes the city from enforcing the notice requirement against other individuals in the future.
See Roberts,
