¶ 1. This is a zoning case in which we review a conclusion reluctantly reached by the court of appeals that the law of this state may require a basement to be destroyed in order to save it from being flooded. Judge Michael Hoover aptly noted the irony in his opinion for the court of appeals: "applicable law compels a harsh result" in that "we order the certain destruction of [a] basement in order to avoid the possibility that it may be damaged in a flood." State v. Outagamie County Bd. of Adjustment, No. 98-1046, unpublished slip op. at 2 (Wis. Ct. App. Sept. 22, 1998).
¶ 2. David and Barbara Warning own a ranch home in the Town of Bovina, located in the 100-year Flood Fringe District of Outagamie County. The Warnings' basement floor falls below the flood protection elevation required by the county's floodplain zoning ordinance. The Warnings wanted to add a sun porch *621onto their home, but were denied a building permit because of the basement floor violation. They sought and obtained a variance to allow the nonconforming basement to continue to exist.
¶ 3. The State, for the Department of Natural Resources (DNR), initiated certiorari review in the circuit court, contending that the basement was illegal and the variance improperly granted. The circuit court affirmed the issuance of the variance. The court of appeals reversed, noting, however, the anomaly of using a zoning law the purpose of which is to protect hasements to precipitate the likely regulatory destruction of one.
¶ 4. What compelled this anomalous result, according to the court of appeals, was our decision in State v. Kenosha County Board of Adjustment, 218 Wis. 2d 396, 415, 577 N.W.2d 813 (1998), as well as Wis. Admin. Code § NR 116.13(2) (Register, June 1996, No. 486). Kenosha County eliminated the previous distinction between area and use variances and established a "no reasonable use of the property" standard for the issuance of either type of variance, thereby making all variances almost impossible to obtain. The administrative rule prohibits outright the issuance of a variance to allow a basement floor that falls below the regional flood elevation to continue to exist.
¶ 5. Kenosha County's establishment of a single standard for measuring the "unnecessary hardship" required for the issuance of both use and area variances has practically eliminated the efficacy of variance procedure as a remedy against individual injustices caused by sweeping land use regulations, as the Warnings' case vividly demonstrates. Such a radical change in variance law was unwarranted. I would overrule the case and restore the distinction between *622use and area variances to the law of zoning in this state. Two members of the court join me in this conclusion.1 Two other members of the court read Kenosha County differently, but nevertheless conclude that it is not an impediment to the Warning's variance, and therefore concur.2 Four members of the court3 join me in concluding that because Wis. Admin. Code §NR 116.13(2) categorically prohibits variances for any deviation from basement elevation requirements in floodplains, it inexorably conflicts with the discretionary authority over variances vested in local boards of adjustment by state statute, and therefore must give way. Accordingly, we reverse the court of appeals, and reinstate the circuit court's decision affirming the Outagamie County Board of Adjustment's issuance of a variance to the Warnings.
¶ 6. Before proceeding, a word about the stakes, which the dissent suggests I have mischaracterized. As a practical matter, this case is about a too-deep basement, which may or may not eventually be subject to an enforcement action but presently is preventing a homeowner from building a sun porch. If that were all there was to it, we never would have granted review. As a legal matter, however, the stakes are very high. This case is about an erroneous precedent of this court that severely restricts almost to the point of eliminating the availability of zoning variances in this state, and a DNR rule that conflicts with a statute. The dissent is *623therefore correct that the authority of the DNR and the principles of stare decisis are on the line.
¶ 7. But more fundamentally, this case is about individual private property rights, the scope of the police power to regulate them through zoning, and the statutory authority of local boards to strike a balance between the two through variances. My focus is not on saving the basement or allowing the sun porch, but on restoring balance and common sense to the law of zoning in this state. The irony inherent in the notion of destroying a basement in order to save it only serves to illustrate the flaws in the erroneous precedent and the conflicting rule; it does not provide the ultimate justification for this opinion.
HH
¶ 8. The relevant facts are undisputed. David and Barbara Warning own 1.77 acres of land in the Town of Bovina in Outagamie County. The Warnings' property is located within the 100-year Flood Fringe District of Outagamie County and is regulated by the Outagamie County Zoning Ordinance and the Outagamie Shoreland-Floodplain-Wetland Ordinance (collectively, "the Ordinance").
¶ 9. The Ordinance defines "flood fringe" as "[t]hat portion of the floodplain outside of the floodway, which is covered by floodwaters during the regional flood. It is generally associated with standing water rather than rapidly flowing water." Ordinance § 16.05. The Ordinance defines "regional flood" as a flood which, because of the area's physical characteristics, may be expected to occur "once in every 100 years." Id. The chance of a regional flood occurring in any given year, therefore, is one percent. Id. The Ordinance requires that the first floor of a residential building *624located in the flood fringe, including a basement floor, be two feet above regional flood elevation. Ordinance § 16.32(4)(b)l.
¶ 10. In 1980, the Warnings applied for and received a conditional use permit from the Outagamie County Zoning Committee to place fill and a mobile home on their property, which they knew was in the Flood Fringe District. The County required the placement of fill on the land so that the mobile home would be at the proper elevation. The mobile home complied with flood proofing requirements.
¶ 11. In 1984, the Warnings applied for and received a second building permit to replace the mobile home with a permanent single-family home. The building inspector issued a building permit to the Warnings but did not advise them that they needed to obtain a zoning permit from the Outagamie County Zoning Department, and they did not do so.
¶ 12. With the building permit in hand, the Warnings constructed a three-bedroom ranch house with a basement and attached garage. The basement floor of the house fell 3.7 feet below the 100-year regional flood elevation and 5.7 feet below the flood protection elevation, in violation of the Ordinance and the Wisconsin Administrative Code.4
¶ 13. In 1995, 11 years after their home was built, the Warnings applied for a third building permit, this time to add a sun porch to their home. The Outagamie County zoning administrator denied the Warnings' request because their home did not meet the flood protection elevation requirements due to the *625basement floor violation. The zoning administrator informed the Warnings thát without a variance, they could not obtain a building permit to add the sun porch to their nonconforming structure.
¶ 14. The Warnings applied to the Outagamie County Board of Adjustment for an "after the fact" variance for their nonconforming basement floor.5 A hearing was held, and the DNR appeared and opposed the variance, arguing that the Warnings' home was not merely nonconforming but "an illegal structure" and that the variance criteria could not be met.
¶ 15. The Warnings noted, and the zoning administrator conceded, that there were other homes in the area with basements below regional flood elevation, but they had apparently been built before the Ordinance was in place. The Warnings also noted that there was no history of flooding in the area, and that filling in the basement or trying to sell the home without a variance would cause a substantial loss. They also pointed out that the sun porch itself would comply with the Ordinance as it would be constructed on fill above flood protection elevation.
¶ 16. There was no community opposition to the variance; only the zoning administrator and the DNR representative objected. They argued that the Warn*626ings had not satisfied the criteria for a variance under the Ordinance. Neither the zoning administrator nor the DNR representative cited § NR 116.13(2) as prohibiting the Board from granting any variance at all in these circumstances.
¶ 17. The Board of Adjustment made findings and voted unanimously to grant the variance, reasoning that:
[T]he hardship experienced by the Warnings was caused by the Town of Bovina and the negligence of the town building inspector for issuing a building permit for the three bedroom ranch style home in 1984. The hardship is not based solely on economic gain or loss, the loss would be substantial. The Board also felt that the proposed addition to the home would comply with the floodproofing requirements.
¶ 18. The State sought certiorari review of the Board of Adjustment's decision in circuit court pursuant to Wis. Stat. § 59.694(10) (1997-98).6 On certiorari review, the DNR argued for the first time that § NR 116.13(2) prohibited any variances for flood elevation deviations. The circuit court affirmed the Board, concluding that the Warnings had at all times acted in good faith, that they would suffer a hardship that was not self-created in the absence of a variance, and that the DNR had waived its argument that § NR 116.13(2) was more restrictive than the Ordinance. Specifically as to hardship, the circuit court applied the court of appeals' decision in State v. Kenosha County Board of Adjustment, 212 Wis. 2d 310, 569 N.W.2d 54 (Ct. App. 1997), and held that the hardship of filling in the base*627ment or moving the residence "would be extremely great" and "unnecessarily burdensome" as compared to the benefits of enforcing the "strict letter of the restrictions."
¶ 19. The State appealed, and shortly thereafter, this court reversed the court of appeals' decision in Kenosha County. Our decision in Kenosha County erased the longstanding distinction between area (or dimensional) and use variances, and instituted a requirement that a property owner seeking either type of variance establish that there is "no reasonable use of the property without a variance". Kenosha County, 218 Wis. 2d at 413-14 (emphasis added). The Warnings, of course, had sought and obtained an area variance for their basement. Before our decision in Kenosha County, area variances had been governed by the "unnecessarily burdensome" standard described in Snyder v. Waukesha County Zoning Board of Adjustment, 74 Wis. 2d 468, 475, 247 N.W.2d 98 (1976), which the court of appeals had followed in its decision in Kenosha County, 212 Wis. 2d at 320.
¶ 20. Evaluating an area variance against a "no reasonable use of the property" standard is a far cry from evaluating it against an "unnecessarily burdensome" standard. Yet our decision in Kenosha County did not overrule or even distinguish Snyder, but simply declared itself "compatible" with its "concerns," without explaining how this could be so, when the earlier case had clearly distinguished between use and area variances and established the more flexible "unnecessarily burdensome" standard for the latter. The court of appeals reluctantly concluded that Kenosha County's new "no reasonable use of the property" test for area variances could not be met in this case. The court also concluded that, in any event, § NR 116.13(2) foreclosed *628the issuance of a variance to allow a basement floor below the regional flood elevation. State v. Outagamie County Bd. of Adjustment, No. 98-1046, unpublished slip op. at 8-9.
¶ 21. We accepted review and heard oral argument on October 6, 1999. We subsequently ordered rebriefing and reargument, which took place on October 4, 2000.
1 — I HH
¶ 22. The interpretation and reconciliation of statutes and ordinances involve questions of law that reviewing courts decide independently. See State v. Ozaukee County Bd. of Adjustment, 152 Wis. 2d 552, 559, 449 N.W.2d 47 (Ct. App. 1989). The Wisconsin Statutes require counties to zone by ordinance all floodplains within their unincorporated areas. Wis. Stat. § 87.30(1). The purpose of floodplain zoning is to promote the public health, safety, and welfare and to minimize flood damage. See Wis. Stat. § 87.30(1); see also § 1, ch. 614, Laws of 1965-66 Vol. II. Outagamie County adopted a combination shoreland-floodplain-wetland zoning ordinance in 1977.
¶ 23. The statutes also authorize counties to create boards of adjustment to make special exceptions, or variances, from the terms of zoning ordinances in harmony with their general purpose and intent. Wis. Stat. § 59.694(1).7 Aboard of adjustment's authority to issue variances is codified in Wis. Stat. § 59.694(7)(c), which describes the broad scope of the power in this way:
*629To authorize upon appeal in specific cases variances from the terms of the ordinance that will not be contrary to the public interest, where, owing to special conditions, a literal enforcement of the provisions of the ordinance will result in unnecessary hardship, and so that the spirit of the ordinance shall be observed and substantial justice done.
¶24. The statute requires a person seeking a variance to prove that he or she will suffer an "unnecessary hardship" in the absence of a variance. Arndorfer v. Sauk County Bd. of Adjustment, 162 Wis. 2d 246, 253, 469 N.W.2d 831 (1991). The hardship must be unique to the property and not a condition personal to the landowner, such as mere inconvenience. Snyder, 74 Wis. 2d at 479. It cannot be self-created. Id. at 476. The hardship is evaluated against the purpose of the zoning restriction at issue. Id. at 473. A variance cannot be contrary to the public interest. Arndorfer, 162 Wis. 2d at 256.
¶ 25. A person aggrieved by the issuance or denial of a variance may commence an action in circuit court seeking the remedy available by certiorari, as the State did in this case. See Wis. Stat. § 59.694(10). A reviewing court must accord a presumption of correctness and validity to a board of adjustment's decision. Snyder, 74: Wis. 2d at 476 (citing Richard W. Cutler, Zoning Law and Practice in Wisconsin § 15 (1967); 4 Edward H. Ziegler, Jr., Rathkopf's The Law of Zoning and Planning § 42.07 (4th ed. 1995); 8A McQuillin, Municipal Corporations § 25.237 (3d ed. 1994)). A reviewing court may not substitute its discretion for that of the board, the entity to which the legislature *630has committed these decisions. Id. at 476; see also Arndorfer, 162 Wis. 2d at 253.
¶ 26. When no additional evidence is taken, statutory certiorari review is limited to: (1) whether the Board kept within its jurisdiction; (2) whether it proceeded on a correct theory of law; (3) whether its action was arbitrary, oppressive or unreasonable and represented its will and not its judgment; and (4) whether the Board might reasonably make the order or determination in question, based on the evidence. Arndorfer, 162 Wis. 2d at 253. In applying this standard, a reviewing court is required to defer to the decision of the board unless it is "unreasonable or without a rational basis. .. .Thus, the findings of the board may not be disturbed if any reasonable view of the evidence sustains them." Snyder, 74 Wis. 2d at 476.
h — ( H-l HH
¶ 27. The critical threshold issue in this case is the proper standard for measuring unnecessary hardship in an area variance case. The Warnings and amicus curiae argue that our decision in Kenosha County improperly altered the test for an area variance from the "unnecessarily burdensome" formulation that had existed since our 1976 decision in Snyder to the "no reasonable use of the property" standard that up to that point had generally been used only in use variance cases.
¶ 28. The import of Kenosha County is that there is now in this state only one test for both area and use variances, and it is such a Draconian one that all variances — whether from area (dimensional) or use zoning restrictions — are nearly impossible to obtain. This, the Warnings and amicus contend, is completely at odds *631with Snyder, in which we clearly established separate standards for area and use variances and said, for reasons related to the differing purposes of area and use zoning, that area variances are generally more readily obtainable than use variances. Snyder, 74 Wis. 2d at 473. They urge that we overrule Kenosha County and restore Snyder's distinction between area and use variances.
¶ 29. Kenosha County was decided unanimously a mere three years ago. Ordinarily, of course, we adhere to the principle of stare decisis. Respect for precedent "promotes the evenhanded, predictable, and consistent development of legal principles, fosters reliance on judicial decisions, and contributes to the actual and perceived integrity of the judicial process." Payne v. Tennessee, 501 U.S. 808, 827 (1991). Fidelity to precedent ensures that existing law will not be abandoned lightly. State v. Stevens, 181 Wis. 2d 410, 441, 511 N.W.2d 591 (1994) (Abrahamson, J., concurring), cert. denied, 515 U.S. 1102 (1995). When existing law "is open to revision in every case, 'deciding cases becomes a mere exercise of judicial will, with arbitrary and unpredictable results.'" Citizens Utility Bd. v. Klauser, 194 Wis. 2d 484, 513, 534 N.W.2d 608 (1995) (Abrahamson, J., dissenting) (citation omitted). Thus, we do not overturn precedent unless there is strong justification. City of Akron v. Akron Ctr. for Reprod. Health, Inc., 462 U.S. 416, 420 (1983). Changing the law is justified only when "precedent has become detrimental to coherence and consistency in the law." Stevens, 181 Wis. 2d at 442 (Abrahamson, J., concurring).
*632¶ 30. Still, the principle of stare decisis is not an "inexorable command,"8 and so the United States Supreme Court has attempted to develop an analytical framework for dealing with challenged precedents, identifying several factors to assist in the decision of whether to overrule:
[Wjhen this Court reexamines a prior holding, its judgment is customarily informed by a series of prudential and pragmatic considerations designed to test the consistency of overruling a prior decision with the ideal of the rule of law, and to gauge the respective costs of reaffirming and overruling a prior case. Thus, for example, we may ask whether the rule has proven to be intolerable simply in defying practical workability; whether the rule is subject to a kind of reliance that would lend a special hardship to the consequences of overruling and add inequity to the cost of repudiation; whether related principles of law have so far developed as to have left the old rule no more than a remnant of abandoned doctrine; or whether facts have so changed, or come to be seen so differently, as to have robbed the old rule of significant application or justification.
Planned Parenthood of Southeastern Pa. v. Casey, 505 U.S. 833, 854-55 (1992) (joint opinion of O'Connor, Kennedy, and Souter, JJ.).9 The four justices who concurred in part and dissented in part in Planned Parenthood v. Casey engaged in a different sort of *633inquiry on the decision to overrule: 1) was the prior case correctly decided; and 2) has it produced a settled body of law? Id. at 999 (Scalia, J., concurring in part and dissenting in part).
¶ 31. Kenosha County cannot withstand either analysis. The rule it established defies practical workability, lacks sufficient justification, and is detrimental to the coherence of the law of zoning in this state. The case, regrettably, was incorrectly decided. The principle of stare decisis does not compel us to adhere to erroneous precedents or refuse to correct our own mistakes. The United States Supreme Court "has never felt constrained to follow precedent" that is "unworkable or. . .badly reasoned," because stare decisis "is a principle of policy and not a mechanical formula of adherence to the latest decision." Payne, 501 U.S. at 827—28. Given how long Kenosha County has been on the books, it has not yet produced a settled body of law such that overruling it would be substantially disruptive to the legal order.
¶ 32. Kenosha County mistakenly merged the previously distinct standards for measuring "unnecessary hardship" in area and use variances, overruling Snyder sub silentio and making it virtually impossible to get a zoning variance of any kind. This has robbed boards of adjustment of the discretion explicitly vested in them by the legislature as a hedge against the individual injustices that occasionally result from the application of otherwise inflexible zoning regulations. Kenosha County purported to be faithful to Snyder and to the rule of deference to the discretion of boards of adjustment, when indeed it was not.10 This point was *634not lost on Judge Neal Nettesheim, as he remarked on the impact of Kenosha County in State ex rel. Spinner v. Kenosha County Board of Adjustment, 223 Wis. 2d 99, 588 N.W.2d 662 (Ct. App. 1998):
[T]he supreme court's decision [in Kenosha County] demonstrates that if any feasible use of the property is available, a hardship cannot exist. Although the supreme court acknowledged, in the same breath, that a board of adjustment's decision is presumptively correct, is committed to the board's discretion and is conclusive if any reasonable view of the evidence sustains the board's finding. . .these deferential phrases ring hollow in light of the court's ultimate holding. The real effect of the court's decision is to significantly curtail a board of adjustment's discretion in such matters. It will be a rare case in which a landowner will be able to meet the "no feasible use" test.
Id. at 110 (Nettesheim, J., concurring.)
¶ 33. I do not perceive that Kenosha County has engendered the sort of reliance that would make it inequitable, harmful, or disruptive to the people of this state to repudiate it at this early point in its doctrinal life. Accordingly, I would expressly overrule it and reinstate Snyder as the proper formulation of the meaning of "unnecessary hardship" for purposes of the issuance of use and area variances.
¶ 34. Wisconsin Statute § 59.694(7)(c) authorizes boards of adjustment to grant variances in cases in *635which a strict enforcement of the zoning code would cause an "unnecessary hardship." Although the statute speaks of variances generally, and does not further define "unnecessary hardship," our law has always treated use variances differently from area variances because of the different purposes underlying use and area zoning. Snyder, 74 Wis. 2d at 473-75. This distinction between use and area variances is well-recognized:
A use variance is one that permits a use other than that prescribed by the zoning ordinance in a particular district. An area variance has no relationship to a change of use. It is primarily a grant to erect, alter, or use a structure for a permitted use in a manner other than that prescribed by the restrictions of a zoning ordinance.
3 E.C. Yokley, Zoning Law and Practice § 21-6 (4th ed. 1979); see also 3 Edward H. Ziegler, Jr., Rathkopf's The Law of Zoning and Planning § 38.01 (4th ed. 1997).
¶ 35. As the court of appeals in Kenosha County noted, statutes governing use and area variances fall into three categories: (1) those which allow use and nonuse (area) variances and which allow nonuse (area) variances to be granted upon a showing of practical difficulty; (2) those which allow use and nonuse (area) variances and require a showing of unnecessary hardship for both; and (3) those which do not allow use variances and require unnecessary hardship for the granting of nonuse (area) variances. See Kenosha County, 212 Wis. 2d at 316-17, (quoting 3 Ziegler, supra § 38.04, at 42). Our statute falls into the second category, allowing both use and area variances upon a showing of "unnecessary hardship."
¶ 36. The general rule throughout the United States recognizes a distinction in the level of hardship *636required to justify area and use variances. "[I]n most states, the courts will approve an area variance upon a lesser showing by the applicant than is required to sustain a use variance." 3 Kenneth H. Young, Anderson’s American Law of Zoning § 20.48, at 580 (4th ed. 1996). Wisconsin has followed the general rule, and in Snyder, we discussed the reason for the distinction:
[T]he fact that area variances are considerably easier to obtain than use variances creates the impression that a minimal showing of difficulty will establish the element of practical difficulty and entitle the landowner to a variance. However, area variances are not more easily obtained because practical difficulties are something much less severe than unnecessary hardship, but because area variances do not involve great changes in the character of neighborhoods as do use variances. This relates to what hardships or practical difficulties may be considered unnecessary or unreasonable in light of the purpose of the zoning law.
Snyder, 74 Wis. 2d at 473.11
¶ 37. Snyder was an area variance case, and we established the following test for the existence of an "unnecessary hardship" sufficient for the issuance of an area variance: " '[w]hether compliance with the strict letter of the restrictions governing area, set *637backs, frontage, height, bulk or density would unreasonably prevent the owner from using the property for a permitted purpose or would render conformity with such restrictions unnecessarily burdensome.'" Snyder, 74 Wis. 2d at 475 (quoting 2 Ziegler, supra § 45-28). We noted that use variances are subject to a different, narrower measure of "unnecessary hardship:"
In State ex rel. Markdale Corp. v. Board of Appeals, 27 Wis. 2d 154, 133 N.W.2d 795 (1965), [a use variance case] the court considered, in relation to an appeal for a use variance, the definition of unnecessary hardship. The court first took note of the New York rule that to justify a finding of unnecessary hardship, it must appear that the property cannot yield a reasonable return when used for the permitted purposes. . . .The court then stated: "A note entitled 'Zoning Variances,' 74 Harvard Law Review (1961), 1396, 1401, suggests the following definition of 'unnecessary hardship' as used in zoning statutes and ordinances with respect to the power of appeals boards to grant variances: "Since the main purpose of allowing variances is to prevent land from being rendered useless, 'unnecessary hardship' can best be defined as a situation where in the absence of a variance no feasible use can be made of the land."
Snyder, 74 Wis. 2d at 474 (citations omitted).
¶ 38. Thus, because variances from use restrictions have the potential to bring about great changes in neighborhood character, "unnecessary hardship" in use variance cases is measured against a higher standard relating to the use of the property, that is, whether a reasonable use of the property is feasible without a *638variance.12 On the other hand, because area variances do not generally change neighborhood character, "unnecessary hardship" in area variance cases is measured against a lower standard relating to the nature of the area restriction in question, that is, whether compliance with the particular area restriction would "unreasonably prevent the owner from using the property for a permitted purpose" or be "unnecessarily burdensome".13
*639¶ 39. This distinction between area and use variances remained intact until Kenosha County. There, the homeowner sought an area variance to build a deck within the 75-foot setback from the ordinary high water mark of Hooker Lake. The Kenosha County Board of Adjustment granted the variance and both the trial court and the court of appeals affirmed. This court reversed, citing the "unnecessarily burdensome" language from Snyder but not applying it, instead adopting the State's suggestion that the case be evaluated on the basis of the "no reasonable use of the property" standard which had previously been applied only to use variance cases. Kenosha County, 218 Wis. 2d at 413. The court said the "no reasonable use of the property" test was "compatible with the concerns we expressed in Snyder," as well as the court of appeals decision in State v. Winnebago County, 196 Wis. 2d 836, 540 N.W.2d 6 (Ct. App. 1995). Kenosha County, 218 Wis. 2d at 413.
¶ 40. In Winnebago County, the court of appeals had evaluated an area variance against the use variance test set out in Snyder. Winnebago County, 196 Wis. 2d at 843-45. It did so, however, because the relief sought by the property owner, while implicating an area regulation (shoreland setback requirements), would have had the practical effect of changing the character of the neighborhood by permitting greater population density (a larger number of smaller lots). The court of appeals in Kenosha County properly saw Winnebago County as a case of a use variance masquerading as an area variance, and therefore distinguished it:
[A]lthough the relief which the landowner sought was necessarily area based, the core question before *640the board was the scope and degree of the future use of the property. The landowner's development plans for the property represented a significant change in the use of the property. Under those circumstances, the area variance request carried a significant impact on the future use of the property. Rathkopf s treatise recognizes that in some instances an area variance is really a use variance in disguise:
'If the variance will permit a use of the land that changes the character of the neighborhood, then it is more likely that the variance will be held to be a use variance. For example, suppose a zoning ordinance requires 800 square feet of lot area per apartment in a multi-family zone, but the board of adjustment approves a variance for construction of an apartment building that would result in there being only 400 square feet of lot area per apartment. On its face it looks like an area variance, because the subject was area. On the other hand, doubling the number of apartment units being built on one lot may have a substantial impact on the character of the neighborhood, perhaps taking it from being "moderate" to "dense." Courts have found that such a variance was a use variance. 3 Rathkopf [The Law of Zoning and Planning] n. 4, § 38.01, at 8 (footnote omitted)(emphasis added).
Although the variance sought in Winnebago County was an area variance, the ultimate effect of the variance, if granted, would have produced a marked change in the scope and degree of the proposed development. Thus, it is not remarkable that the Winnebago County court saw the issue in terms of use, spoke to the issue in those terms, and relied on the "no feasible use" test set out by the supreme court in Snyder.
Kenosha County, 212 Wis. 2d at 319-20.
*641¶ 41. Viewing the area variance in Winnebago County as a use variance in disguise made perfect sense under the facts of that case. In contrast, requiring all area variance applicants to meet the test for a use variance, that is, to demonstrate that there is no reasonable use of the property without a variance, makes little sense. Such a strict standard bears no relationship to the purpose of area zoning, as distinct from use zoning. And, to the extent that it makes all variances nearly unobtainable, it is inconsistent with the language of the enabling statute, which vests boards of adjustment with broad quasi-judicial authority to grant variances for minor deviations from zoning restrictions in order to do substantial justice. See Wis. Stat. §§ 59.694(1) and (7)(c), 59.692(4)(b).
¶ 42. As it stands now, if an area variance applicant has any reasonable use of his property without a variance, a hardship will not exist and no variance can be issued. What this means as a practical matter is that any property owner currently putting his property to some use is disqualified from obtaining a variance to legalize even a minor zoning violation, and is therefore effectively precluded from making otherwise fully legal improvements to his property. For example, a property owner whose home encroaches into the side yard setback in a de minimus way, say, by a foot (perhaps because of a surveyor's error or builder's mistake), will be unable to obtain a building permit to remodel his kitchen or add a deck, because he will never be able to meet the "no reasonable use of the property" test for an area variance to legalize the setback violation. Similarly, a lake homeowner whose home conformed to the shoreline setback when built but no longer does due to shoreline erosion, will be prevented from improving his home, at least to the extent that the improvements *642require a government permit and therefore a variance for the shoreline setback violation that developed over time due to natural causes.
¶ 43. Adequate variance procedure is a practical and legal necessity in the day-to-day administration of modern zoning codes. Use and area zoning are distinct, and exist to promote different types of neighborhood uniformity: uniformity of use, of course, in the former; and uniformity of lot and building size, for example, in the latter. Floodplain zoning exists for the more specific purposes of promoting public health and safety and protecting private property from flood damage.
¶ 44. "Obtaining a variance because of unnecessary hardship is the recognized and approved legal device by which the basic constitutional right of property is reconciled with the paramount right of government to protect by zoning the public health, safety, morals and welfare." McQuillin, supra § 25.166. Variances "are designed to afford a protective device against individual hardships, to provide relief against unnecessary and unjust invasions of the right of private property, and to provide a flexibility of procedure necessary to the protection of constitutional rights." Id. at §25.160.
¶ 45. The unnecessary hardship standard "is neither the same nor as demanding as a takings analysis." 3 Yokley, supra § 21-5 at 86 (Supp. 2000) (emphasis in original). However, the "no reasonable use" test for unnecessary hardship in a use variance case has something of a constitutional ring to it. See Lucas v. South Carolina Coastal Council, 505 U.S. 1003 (1992)(holding that a zoning regulation which deprives property of all economically beneficial or productive use is a categorical regulatory taking). This is *643generally not true of the test for unnecessary hardship in an area variance case:
The hardship that is required for a use variance, i.e., hardship that equates with a lack of a reasonable return or destruction of all beneficial use of the property, has constitutional overtones. The hardship, or practical difficulty, required for a nonuse variance does not, in most states, have those constitutional overtones. In many cases the hardship or practical difficulty necessary for a nonuse variance will consist of the unnecessary deprivation of the full enjoyment of a permitted use.
3 Ziegler, supra § 38.02, at 38-22-23.
¶ 46. Sensible standards for the issuance of area and use variances — standards that bear some relationship to the distinct purposes underlying area and use zoning — are critical to the regulatory "escape valve" function of variance procedure:
It has been said that to preserve the validity of the zoning ordinance in its application to the community in general, the variance provision of the enabling act functions as an "escape valve," so that when regulations that apply to all are unnecessarily burdensome to a few because of certain unique circumstances a means of relief from the mandates of the ordinance is provided.
Yokley, supra § 21-2, at 264.
¶ 47. Clearly, then, while variance procedure exists in part to prevent zoning regulations from operating in such a way as to render private property useless (and therefore avoid regulatory takings), its purposes encompass far more than that alone. "The purpose of variances in the broadest sense is the rendering of justice in unique and individual cases of practical difficulties or unnecessary hardships arising *644from literal application of zoning ordinances." McQuillin, supra §25.172. Limiting the availability of area variances to those situations that resemble regulatory takings operates to unreasonably prevent private property owners from making even highly beneficial, completely legal improvements to their property. Requiring all area variance applicants to demonstrate "no reasonable use of the property" runs counter to the broader purposes of variance procedure.
¶ 48. Thus, the general rule allowing area variances upon a lower standard than that which is required for use variances finds its justification in the fundamental purposes of variance procedure:
The prime justification for requiring less of an applicant for an area variance than is required in the case of a use variance is that the former does not affect the use of the laúd. An area variance is thought not to threaten adjacent land with the establishment of an incompatible use, or to hazard the maintenance of a use which will change the essential character of a neighborhood. Such a variance has some capacity to impose an adverse effect on adjacent land, and standards must be imposed to insure the protection of neighboring property, but in the case of area variances, it is assumed by most courts that adequate protection of the neighborhood can be effected without the imposition of the stringent limitations which have been developed in the use variance cases.
Young, supra § 20.48, at 581.
¶ 49. Snyder was consistent with these longstanding principles of variance law. Kenosha County was not.14 Overruling the latter is not a mere exercise *645of judicial will, but a necessary and justified restoration of balance and coherence to variance law in this state.
¶ 50. This is not to say that area variances should be, or are, automatic or easy to obtain. "The power to grant a variance is an exceptional one and it is said should be sparingly exercised." Yokley, supra § 21-4, at 83 (Supp. 2000); see also Young, supra § 20.23, at 497 ("courts have repeatedly emphasized that the exceptional power to grant variances should be used sparingly, and never simply to enable one landowner to enhance his income at the expense of his neighbors, or to the detriment of the community plan"). The burden is on the applicant to prove unnecessary hardship, and this "burden of proof is heavy; the reasons for granting a variance must be substantial." Id. § 20.20, at 479. It bears emphasizing that variances — whether from use or area restrictions — can never be authorized when contrary to the public interest.
¶ 51. What remains, then, is to examine the record in this case against Snyder's "unnecessarily burdensome" test for an area variance. Deferring as we must to the Board's discretion, I agree with the circuit *646court that the record supports the Board's conclusion that compliance with the strict letter of the basement floor elevation requirements of the Ordinance would be unnecessarily burdensome under the circumstances of this case.
¶ 52. The State considers the Warnings' home to be an "illegal structure." To bring it into compliance with flood elevation requirements (regardless of whether they added a sun porch), the Warnings would have to fill in the basement or move the house. The hardship suffered under either scenario — basically, the complete loss of the basement — is substantial, far outweighing the benefits of enforcing the strict letter of the flood elevation requirements. True, one sure way to avoid basement flood damage is to get rid of the basement altogether, but this is such regulatory overkill under the circumstances of this case that the Board's action in granting the variance was completely justified.
¶ 53. Furthermore, the hardship is unique to the property and not "self-created" to the extent that the Warnings built their home (with the nonconforming basement floor) pursuant to and in reliance upon a building permit duly issued by the Town of Bovina. They have been unreasonably and unnecessarily prevented from making conforming and beneficial improvements to their property because of the basement floor violation. Legalizing the basement by issuing a variance is not contrary to the public interest and does not have a detrimental impact on neighborhood character. Since the sun porch itself will comply with floodplain regulations, the variance does not increase the nonconformity and therefore does not defeat the purpose of the floodplain ordinance, which is *647to minimize flood damage and protect health and safety. Accordingly, applying the proper variance test and standard of review, I conclude that the record supports the Board's finding of unnecessary hardship sufficient to justify a variance in this case.
IV
¶ 54. The court of appeals also held that Wis. Admin. Code § NR 116.13(2) foreclosed the issuance of any variance that has the effect of allowing a residential basement floor below the regional flood elevation. The State did not make this argument before the Board, but raised it for the first time in the circuit court. Relying on Goranson v. DILHR, 94 Wis. 2d 537, 545, 289 N.W.2d 270 (1980), the circuit court held that the State had waived the § NR 116.13(2) argument. The court of appeals disagreed, concluding that the Warnings had failed to address the State's argument against waiver and therefore conceded the issue was not waived.
¶ 55. It is settled law that to preserve an issue for judicial review, a party must raise it before the administrative agency. Judicial review of administrative agency decisions contemplates review of the record developed before the agency.15 Ordinarily an appellate court will not consider issues beyond those properly raised before the administrative agency, and a failure *648to raise an issue generally constitutes a waiver of the right to raise the issue before a reviewing court.16
¶ 56. One exception to this rule permits consideration of an issue otherwise waived if all the facts are of record and the issue is a legal one of great importance.17 Whether §NR 116.13(2) prohibits boards of adjustment from granting variances for residential floors below regional flood elevation is a question of law that has been briefed in this court by both parties and is an issue of great importance to property owners, the DNR, boards of adjustment and the courts. Accordingly, we will look past the waiver in this case and decide the issue.
¶ 57. Wisconsin Admin. Code § NR 116.13(2) provides:
RESIDENTIAL USES, (a) Any structure or building used for human habitation (seasonal or permanent), which is to be erected, constructed, reconstructed, structurally altered or moved into the floodfringe area shall be placed on fill with the *649finished surface of the lowest floor, excluding basement or crawlway, at or above the flood protection elevation. If any such structure or building has a . basement or crawlway, the surface of the floor of the basement or crawlway shall be at or above the regional flood elevation and shall be floodproofed to the flood protection elevation in accordance with s. NR 116.16. No variance may be granted to allow any floor below the regional flood elevation. An exception to the basement requirement may be granted by the department, but only in those communities granted such exception by the federal emergency management agency (FEMA) on or before March 1986 (emphasis added).
¶ 58. The rule flatly prohibits any variance that would allow a residential floor below the regional flood elevation, unless the Federal Emergency Management Agency (FEMA) has granted a community-wide exception, a circumstance both parties concede is not present here. The court of appeals held that §NR 116.13(2) prohibited the issuance of a variance for the Warnings' basement.
¶ 59. However, the administrative rule stands in direct conflict with state statute. To the extent that it administratively prohibits all variances in a certain class of cases, it conflicts with the general grant of authority to county boards of adjustment over variance decisions. See Wis. Stat. § 59.694(1) and (7).
¶ 60. An administrative agency cannot exercise its rulemaking authority in contradiction of the will of the legislature as expressed in the statutes. See Wis. Stat. §§ 227.10(2) ("[n]o agency may promulgate a rule which conflicts with state law") and 227.11(2)(a); Seider v. O'Connell, 2000 WI 76, ¶ 24, 236 Wis. 2d 211, 612 N.W.2d 659. This administrative rule purports to *650circumscribe the authority over variance decisions that the legislature has explicitly vested in local boards of adjustment.
¶ 61. There is nothing in the DNR's general grant of authority to regulate floodplains that permits the agency to write rules that nullify the discretion over variance decisions that the legislature has specifically committed to local boards of adjustment. Thus, to the extent that § NR 116.13(2) prohibits county boards of adjustment from granting variances from flood elevation requirements where the proper statutory standards for such variances have otherwise been met, it is invalid.18 Accordingly, the rule is no impediment to our sustaining the variance here.
V
¶ 62. The court of appeals decided this case on the basis of Kenosha County and § NR 116.13(2) and therefore did not address whether the issuance of the variance was consistent with the procedures and standards of the Outagamie County Shoreland-Floodplain-Wetland Zoning Ordinance. We conclude that it was.
¶ 63. The Ordinance promulgates the variance statute at the local level, and authorizes the Board to *651grant variances which are not contrary to the public interest where, "owing to special conditions unique to the property, a literal enforcement [of the zoning code] will result in unnecessary hardship, so that the spirit of the chapter shall be observed, public safety and welfare secured and substantial justice done." Ordinance § 16.40(2)(b); Wis. Stat. § 59.694(7)(c). Section 16.40(4) of the Ordinance sets out the procedure for the issuance of a variance, and also provides:
In all cases, a variance:
(a) Shall not permit any change in established flood elevations or profiles.
(b) Shall not be granted for a condition that is common to a group of adjacent lots or premises.
(c) Shall not be granted unless it is shown that the variance will not be contrary to the public interest or damaging to the rights of other persons or property values in the area.
(d) Shall not be granted for actions which require an amendment to this chapter, the maps or other ordinances of the county.
(e) Shall not have the effect of allowing or expanding a use or structure which is prohibited in that zoning district.
(f) Shall not be granted solely on the basis of economic gain or loss.
(g) Shall not be granted for a self created hardship.
(h) Shall not permit a lower degree of flood protection in the floodway area than the flood protection elevation, as defined in § 16.05. In the flood fringe area a lower degree of flood protection than the *652flood protection elevation may be allowed pursuant to § 16.35(2).
¶ 64. The Board concluded that the Warnings were facing a unique and unnecessary hardship sufficient to meet the criteria for a variance under the Ordinance. The State, however, argues that according to § 16.40(4)(h), variances for deviations from flood-proofing requirements are allowed only pursuant to § 16.35(2), and that section does not allow variances for nonconforming structures that are used for human habitation. Thus, according to the State, the Warnings are ineligible for a variance under the Ordinance. We disagree.
¶ 65. Section 16.32(4)(b)(2) of the Ordinances establishes the zoning standards for development in flood fringe areas and specifically allows variances for basement floors below regional flood elevation in buildings used for human habitation, referring back to the variance procedures in § 16.40. Section 16.40(4)(h) allows for variances under these circumstances, and refers back to § 16.35. Section 16.35(2) provides:
16.35 EXISTING STRUCTURES IN FLOOD FRINGE AREAS. (1) All modifications or additions to any nonconforming structure which do not exceed 50% of its assessed value adjusted to the most current equalized value for the municipality shall be placed on fill or protected by floodproofing measures pursuant to § 16.32(4) of this chapter. No structural modification or addition to any nonconforming structure as long as such use continues shall exceed 50% of its assessed value for the municipality, unless the entire structure is permanently changed to a conforming structure with a conforming use.
(2) Where compliance with the provisions of the above section would result in unnecessary hard*653ship and only where the structure will not he either used for human habitation or be associated with high flood damage potential, the Board of Adjustment using the procedure in § 16.40 may grant a variance from these provisions in accordance with the criteria listed below. Modifications or additions to structures or buildings which are protected to elevations lower than the flood protection elevation may be permitted if:
(a) Human lives are not endangered.
(b) Public facilities, such as water and sewer, are not to be installed.
(c) Flood depths will not exceed 4'.
(d) Flood velocities will not exceed 2' per second.
(e) The structure will not be used for storage of materials described in § 16.32(4)(e) (emphasis added).
¶ 66. Thus, the Ordinance seems to both allow and disallow variances for residential basement floors below regional flood elevation. What §§ 16.32 and 16.40 expressly authorize, § 16.35 prohibits. The conflict between these provisions is essentially irreconcilable. We generally attempt to harmonize conflicting statutory provisions to give effect to the leading idea behind the statute. See State v. Schaller, 70 Wis. 2d 107, 110, 233 N.W.2d 416 (1975). Where one provision in a statute renders another a nullity, it is not given effect. Yanta v. Montgomery Ward & Co., 66 Wis. 2d 53, 66, 224 N.W.2d 389 (1974). We conclude, therefore, that § 16.35(2) is unenforceable to the extent that it purports to completely prohibit variances for residential basement floors below regional flood elevation.
¶ 67. In any event, § 16.35(2) refers back to § 16.35(1), which, although awkwardly phrased, *654appears to exclude from variance requirements any additions to existing nonconforming structures which do not exceed 50 percent of the structure's value, so long as the addition is placed on fill or otherwise flood-proofed. There is no evidence that the Warnings' proposed sun porch exceeds 50 percent of the home's value. Furthermore, the sun porch will be placed on fill at or above the flood protection elevation. Therefore, the issuance of the variance does not increase the nonconformity in violation of the Ordinance.
VI
¶ 68. In summary, I would overrule Kenosha County and restore the distinction between use and area variances in the law of zoning in this state. I conclude that "unnecessary hardship" for purposes of a use variance is established when it is shown that no reasonable use of the property is feasible without a variance. "Unnecessary hardship" for purposes of an area variance is established when it is shown that strict compliance with an area restriction would unreasonably prevent the property owner from using the property for a permitted purpose or is otherwise unnecessarily burdensome.
¶ 69. Both standards are considered in light of the purpose of the zoning restriction in question and with the goal of doing substantial justice as between the individual property owner and the community. The reasons for granting either type of variance must be substantial and not contrary to the public interest or detrimental to the community plan. Considered against the proper standard, and deferring to the discretion of the Board of Adjustment as the statutorily designated arbiter of local zoning disputes, I conclude *655that the Board's issuance of a variance to the Warnings under the circumstances of this case was justified.
¶70. Further, we conclude that Wis. Admin. Code § NR 116.13(2) conflicts with Wis. Stat. § 87.30(lg) and is therefore invalid to the extent that it prohibits all variances for residential floors below regional flood elevation. Finally, we conclude that the Board's action complied with the procedures in the Outagamie County Shoreland-Floodplain-Wetland Zoning Ordinance. The variance in this case is fully consistent with the spirit of the Ordinance, public safety and welfare, and substantial justice.
By the Court. — The decision of the court of appeals is reversed.
Justices William A. Bablitch and David T. Prosser, Jr. join this opinion in its entirety.
See concurring opinion of Justice N. Patrick Crooks, joined by Justice Jon P. Wilcox.
Justices Wilcox and Crooks join Sections IV and V of this opinion.
The 100-year regional flood elevation is the level to which flood waters will rise during a 100-year flood. The flood protection elevation is an elevation two feet above the 100-year flood elevation. Wis. Admin. Code § NR 116.03(20)(41)(June 1996).
Section 16.32(4)(b)2 of the Outagamie County Shoreland-Floodplain-Wetland Zoning Ordinance states:
The basement floor may be placed at the regional flood elevation, providing it is floodproofed to the flood protection elevation. Where FEMA has granted a community-wide exception, the basement floor may be placed at an elevation lower than the regional flood elevation providing it is in compliance with § 16.37. If FEMA has not granted an exception, requests to construct a basement floor below regional flood elevation must be considered a variance requiring action of the Board of Adjustment as outlined in §16.40 (emphasis supplied).
All subsequent references to the Wisconsin Statutes are to the 1997-98 version unless otherwise indicated.
Wisconsin Statute § 59.694 is the former Wis. Stat. § 59.99 (1993-94), renumbered by 1995 Wis. Act 201 (effective September 1, 1996).
Burnet v. Coronado Oil & Gas Co., 285 U.S. 393, 405 (1932)(Brandeis, J., dissenting).
Citing, respectively, Swift & Co. v. Wickham, 382 U.S. 111 (1965); United States v. Title Ins. & Trust Co., 265 U.S. 472 (1924); see Patterson v. McLean Credit Union, 491 U.S. 164 (1989); see Burnet, 285 U.S. 393.
Both the concurrence and the dissent insist that stare decisis requires us to stick with State v. Kenosha County Board *634of Adjustment, 218 Wis. 2d 396, 577 N.W.2d 813 (1998). The court's fidelity to precedent, however, only goes so far. Nobody minded that Kenosha County effectively overruled Snyder v. Waukesha County Zoning Board of Adjustment, 74 Wis. 2d 468, 247 N.W.2d 98 (1976).
Contrary to the assertion in the dissent, I do not recommend that Kenosha County be overruled because it "prevents Wisconsin from joining other jurisdictions that distinguish area and use variances." Dissent at ¶ 133. Wisconsin followed the majority rule in distinguishing between area and use variances until Kenosha County took us outside the norm. I advocate overruling Kenosha County in order to return Wisconsin to the majority, not to join it for the first time.
The cases seem to use the phrases "no reasonable use" and "no feasible use" interchangeably. The concept is perhaps better expressed as I have stated it above: whether a reasonable use of the property is feasible without the variance.
The dissent says that this distinction in the standards for use and area variances deviates from the plain language of the variance statute. Dissent at ¶¶ 134-36. The truth is that any judicially created standard for evaluating "unnecessary hardship" will deviate from the plain language of the statute, because the statute does not define the term. Snyder's separate standards for use and area variances are judicial gloss. Kenosha County's single, "no reasonable use" standard is judicial gloss. I am not a proponent of judicially enhancing statutes beyond their text. However, in this area at least, and in most states, judicial standards have been attached to variance enabling statutes in order to give content and meaning to the broad term "unnecessary hardship," to avoid invalidating the statutes as improper delegations of discretionary power without adequately defined standards. See 3 Kenneth H. Young, Anderson's American Law of Zoning §§20.08, 20.16, at 452-53 (4th ed. 1996); 3 E.C. Yokley, Zoning Law and Practice § 21-3 (4th ed. 1979). Judicially created standards for measuring "unnecessary hardship" in variance cases have been around since the inception of zoning. It is a little late in the interpretive history of this statute to suddenly become fastidious about its plain language, unless one advocates no standard at all. I do not read the dissent as doing that.
The dissent incorrectly characterizes Kenosha County as merely "clarifying" the "proposed binary analysis" in Snyder. *645Dissent at ¶ 138. Snyder was not a mere "proposal." It was the law. And (at the risk of overemphasizing this point), Kenosha County did not merely "clarify" Snyder, it overruled it sub silen-tio by adopting a single, "no reasonable use" test for all variances. On this point the concurrence, too, is wrong. Kenosha County cannot be explained away. Clarity in this area requires that the decision be overruled. Strained attempts to "explain" or "clarify" an erroneous precedent in order to avoid the difficult step of overruling it, tend to generate confusion and ultimately disrespect for the law.
Omernick v. DNR, 100 Wis. 2d 234, 248, 301 N.W.2d 437 (1981) cert. denied, 454 U.S. 883 (1981) (citing Cobb v. PSC, 12 Wis. 2d 441, 107 N.W.2d 595 (1961)) (referring to review pursuant to ch. 227).
Goranson v. DILHR, 94 Wis. 2d 537, 545, 289 N.W.2d 270 (1980); Gallagher v. Industrial Comm'n, 9 Wis. 2d 361, 368, 101 N.W.2d 72 (1960).
17 "The usual reasons for not considering such questions are not present here in that there is no problem of an incomplete record, and the opposing party has had the opportunity to brief the question and present its arguments. This court has said that whether it should review an issue raised here for the first time depends upon the facts and circumstances disclosed by the particular record. The question is one of administration not of power, [citations omitted] Since the issue raised concerns the jurisdiction of the board of review, a subject properly reviewable on certiorari, it should be considered."
State ex rel. Gen. Motors Corp. v. Oak Creek, 49 Wis. 2d 299, 319-20, 182 N.W.2d 481 (1971).
The dissent characterizes this conclusion as a "judicial grant" of "plenary power" to boards of adjustment that undermines the DNR's ability to regulate floodplains. To the contrary, this conclusion merely recognizes and gives effect to a legislative grant of power to boards of adjustment. The DNR is free to regulate floodplains to its heart's content, provided it does so consistently with the statutes. The legislature, however, has explicitly committed variance decisions to local boards of adjustment, not the DNR. Wis. Stat. § 59.694(1).
State v. Kenosha County Bd. of Adjustment, 218 Wis. 2d 396, 577 N.W.2d 813 (1998).