Margenau v. Bowlin, 12 P.3d 1214, 1216 (Colo.App. 2000). Both the Schneiders and the Drakes assert that the trial court erred in not applying the test set forth in Zavislak v. Shipman, 147 Colo. 184, 362 P.2d 1053 (1961). There, the supreme court held that a court may exercise its equitable powers when a restrictive covenant no longer serves the purpose for which it was imposed or when the circumstances have changed and the enforcement would impose an oppressive burden without any substantial benefit.

As the district court noted, it is not apparent why the DeJeans did not seek to quiet title to remove or cancel the single-family restriction as a cloud on their title. See Zavislak v. Shipman, 362 P.2d 1053, 1055 (Colo. 1961). Regardless, the DeJeans' arguments are specific to Grosz and the Rodells, and we consider only whether these defendant-appellants may enforce the title restriction.

The appellants argue that this twelve-year period has not yet run for them. Their argument is premised on the theory that principles of state property law should determine the validity of the restrictions, Amoco Production Co. v. United States, 619 F.2d 1383, 1387 (10th Cir. 1980); State Land Board v. Corvallis Sand Gravel Co., 429 U.S. 363, 378-81, 97 S.Ct. 582, 590-92, 50 L.Ed.2d 550 (1977), and that under Colorado property law, restrictive easements and covenants become invalid and unenforceable when changing conditions frustrate the original purpose of the easements or covenants. See Zavislak v. Shipman, 147 Colo. 184, 362 P.2d 1053 (1961); Cole v. Colorado Springs Co., 152 Colo. 162, 381 P.2d 13 (1963). Appellants rely on the Amoco case to urge that Colorado property law should be applied in construing the statute of limitations.

It is not apparent why the action was not brought to quiet title. See Zavislak v. Shipman, 362 P.2d 1053 (Colo. 1961)(affirming the trial court's order "removing the cloud" created by restrictive covenants concerning set back requirements based on changed circumstances and "quieting the title"). In the absence of an action to quiet title, judgment may enter only as to the parties to this action.

Colorado law recognizes that courts have the power to remove or cancel restrictive covenants when “it is shown that the restrictive covenants no longer serve the purpose for which they were imposed and are no longer beneficial to those claiming under them.” Zavislak v. Shipman, 147 Colo. 184,362 P.2d 1053, 1055 (1961). Here, the Plaintiffs assert that circumstances have changed substantially over the past 25 years, such that enforcement of the Agreements imposes an oppressive burden prohibiting development of the Property.

We answer the question in the negative and hold that the covenants are valid and enforceable. The pertinent rule of law applicable to this case is most recently set out in Zavislak v. Shipman, 47 Colo. 184, 362 P.2d 1053, wherein this court adopted the language of McArthur v. Hood Rubber Co., 221 Mass. 372, 109 N.E. 162, as follows: "* * * When the purpose for which the restriction was imposed has come to an end, and where the use of the tract of land for whose benefit it was established has so utterly changed that no party to the bill could be heard to enforce it in equity or would suffer any damage by its violation, * * * a proper case is made out for equitable relief.* * *"