delivered the opinion of the court:
In this cause, the city of Rock Island appeals from the judgment of the circuit court of Rock Island County which was entered, following a bench trial, as a result of which the trial judge entered an order setting aside a deed executed by plaintiffs which conveyed approximately 22 acres for a right-of-way to construct a road on what is described as 92d Avenue. In this action, which was filed as a mandamus action, the court also ordered defendant to institute condemnation proceedings to acquire the property involved, which, at that time, was occupied by a completed roadway constructed by the city of Rock Island, as part of 92d Avenue.
The action which was instituted by plaintiffs is asserted to be a mandamus action. Plaintiffs predicate that action upon a written agreement entered into on November 14,1970, between the city of Rock Island and the plaintiffs which provided, in part:
“It is agreed by the City of Rock Island, Illinois, that 92nd Avenue from Route 67 (Moffitts’ property) west and north of the Centennial Expressway will be constructed and completed within 5 years from this date or the deed conveying said right-of-way shall be returned.”
As part of the agreement defendant agreed to stub one water and one sewer line under 92d Avenue prior to the construction of the improvement, to be used when water and sewer service became available to the area and was desired by plaintiffs. As part of the understanding between the parties, also, the city agreed that the farm premises of the plaintiffs would be rezoned to a commercial zoning classification. The right-of-way acquisition was approved by the city council and a payment of *30,000 was authorized and paid to the plaintiffs for which the right-of-way was conveyed to the defendant city of Rock Island.
Appellant states that apparently an escrow arrangement had been worked out but that the right-of-way deed actually was recorded and that plaintiffs did not object to the recording of said right-of-way deed which vested the right-of-way title in the city of Rock Island.
The evidence indicated that the fair market value of the property which was conveyed, at the time of the conveyance, was between *86,000 and *110,000. It was, however, anticipated that the extension of 92d Avenue to the Centennial Expressway would encourage plaintiffs to *852develop the remainder of their property for a commercial venture and would substantially enhance the value of the remainder of the property.
It is shown by the record that the city (working with the county) was to obtain the right-of-way for the road, which was to be constructed and which would establish a connection between the Centennial Expressway and 92d Avenue. Apparently, all of the road was in fact constructed on the right-of-way to a point 1% miles from the connection to the Centennial Expressway. No taxes were paid on the property conveyed for the right-of-way after such conveyance to the city of Rock Island. Sometime after the construction of the roadway was undertaken by the city (with the county participating), the State of Illinois, acting through its representatives, advised the city and county that the planned connection was not consistent with the plans made by the State with regard to the Centennial Expressway and that the city and county could not proceed with the Bz-mile connection to the expressway; that the State would take over the obligation of constructing the remaining Bz-mile connection to the Centennial Expressway. The State took over and had entire control of construction of this portion of 92d Avenue and the connection to the Centennial Expressway.
It is shown of record that the city at all times kept requesting that the State complete the construction of this roadway connection. It appears that priorities in construction of roads by the State postponed construction of the connecting road, even though the State indicated it would be so constructed when funds became available for the State to construct such connecting road and junction with the Centennial Expressway. Meanwhile, the city, as a result of its agreement to stub a water and sewer line, remained ready and willing to do so and to complete the connection at any point where plaintiffs might designate the connections were desired. No such designation was made by the plaintiffs. It was also shown that the cost of the water and sewer facilities to the city would be approximately *200,000 as of time of the hearing instead of *66,000 at the time of the agreement. As of the time of the hearing in this cause, and since that time, the State project has not yet been completely funded, and no specific time when such project would be completed has as yet been determined, although the State has indicated that the project would be completed.
Prior to the filing of the instant action on March 23,1978, no request was made by the Moffitts for reconveyance of the property referred to involved in the right-of-way, even though the five-year period mentioned in the right-of-way agreement had expired on November 16, 1975, and the action is based on the failure of the city to complete the road connection. The sum of *30,000 which was received by the Moffitts was not tendered to the city or to any city official, prior to filing the action, as a *853return of purchase moneys. Although the *30,000 was “tendered,” by recital, in the original and the amended complaints, the defendant city of Rock Island filed a motion to dismiss on the ground of failure to make a demand and, also, of failure of plaintiffs to tender the money prior to instituting the suit. The trial court denied the motion to dismiss.
On appeal in this court, defendant city of Rock Island contends that the amended complaint should have been dismissed for failure to allege that a reconveyance of the right-of-way sought to be directed by the trial court was previously demanded and that the demand was refused, or that such demand would have been unavailing. Failure to allege a demand normally renders a complaint for mandamus defective. Eley v. Cahill (1970), 126 Ill. App. 2d 272, 261 N.E.2d 819.
The plaintiffs point out that, obviously, the defendant was not in a position to complete the construction of 92d Avenue, in view of the fact that the State had the sole authority and power to do so, and a demand on the city to that effect would have been unavailing. The action which was filed by the plaintiffs not only sought to have the trial court direct that the city reconvey the right-of-way property upon the tendered return of the *30,000 received from the city, but, also, to require the city to institute condemnation proceedings to reacquire that property then already occupied by a completed roadway as part of 92d Avenue.
In the amended complaint there is no allegation that a demand for reconveyance was made. The testimony presented at the trial established that no demand in fact was made and that there was no tender of the purchase money to the city prior to the filing of the complaint. Technically, the defendant’s motion to dismiss should have been granted under such circumstances.
In connection with the issues involved in this case, the city of Rock Island also asserts that there was in fact a waiver of the provision of the contract relating to the five-year period by conduct of the plaintiffs. No demand was made at the time the five-year period expired by the plaintiffs and plaintiffs knew that the city could not complete the connection to the expressway, but had completed all but 11* miles of 92d Avenue and was also in the process of or ready to construct the facilities for water and sewer service under the terms of the contract. Such evidence of apparent waiver could arise from the failure to demand strict compliance with the contract provision when time for performance had expired. (See Schmahl v. Aurora National Bank (1941), 311 Ill. App. 228, 35 N.E.2d 689.) A provision of this type could be waived by a party benefiting from it, and such waiver could have been determined to have been made by reason of the activities of the plaintiffs in this case. It is true that they contend that they received no benefit, but they did have a rezoning to commercial classification of their adjoining premises and, *854also, had provision made for available water and sewer lines which could be stubbed at points desired by plaintiffs, as noted in the record. See also Jacobs v. Carroll (1977), 46 Ill. App. 3d 74, 360 N.E.2d 136; Bartels v. Denler (1975), 30 Ill. App. 3d 499, 333 N.E.2d 640.
The reliance of plaintiffs on the cases of People ex rel. King v. Lorenz (1966), 34 Ill. 2d 445, 216 N.E.2d 123, and Robinette v. Department of Public Works & Buildings (1971), 2 Ill. App. 3d 438, 276 N.E.2d 804, is misplaced. These cases involve the enforcement of conditions contained in the deed of dedication or the recorded plat, neither of which is involved in the case at bar. Likewise, this factual situation in the instant case does not involve a reservation of an interest by the person conveying the subject property, as occurred in People ex rel. Department of Public Works & Buildings v. Mokres (1974), 28 Ill. App. 3d 422, 328 N.E.2d 357.
The plaintiffs contend that a demand would have been unavailing since the city could not possibly have proceeded with the program in view of the fact that the State had taken control of the program and was in the sole position to complete the connection for the lM-mile stretch to the expressway.
Under such circumstances, in view of the fact that the State had assumed control of the project during the five-year period and prior to the expiration of five years from the date of the agreement, it appears that a supervening impossibility of performance, not permanent in nature, is involved in the case. Under such circumstances, equitable considerations would require that the city be relieved of its obligation on the basis of impossibility of performance, but be required, if there is a change in the impossibility of performance situation, to do what is required to cause completion of the construction and connection to the expressway. It is clear that the city has sought to do this and continues to do so. While the parties have not alluded specifically to the impossibility of performance by the city, this circumstance operates to relieve the city of an obligation to perform a function rendered impossible by the State. The “takeover" by the State was wholly unforeseeable and not in any manner the fault of the city. Courts now grant relief to parties involved in this situation by discharging promisor of his obligation rendered impossible to perform where a supervening impossibility of performance occurs. The city of Rock Island is thus relieved of its obligation to complete the connection within the five-year period. See Restatement of Contracts §§457, 462 (temporary impossibilities) (1932), and 17 Am. Jur. 2d Contracts §408, at 856-57 (1964).
Where equitable considerations are involved, as in the instant case, such equities must in fact apply so far as the parties are concerned on the basis of the facts in the instant case disclosing a supervening impossibility of performance, not permanent in nature. Under the facts and *855circumstances in this case, it appears that the city is still attempting to cause completion of the roadway connecting to the Centennial Expressway. The city has also caused completion of the construction of the portion of the road covered by the right-of-way and is, and has been, as admitted by the plaintiff S. Wallace Moffitt in testifying, constantly attempting to have the State complete the project to connect to the expressway. The city has undertaken substantial obligations, also, to bring water and sewer connections to the property of plaintiffs.
In view of all the facts and circumstances, we conclude that the trial court improperly directed a reconveyance of the right-of-way property and a direction to institute condemnation proceedings as to said property. On the basis of the record, the connection of 92d Avenue to the Centennial Expressway will be completed when the State obtains funding for such purposes. Where impossibility of performance intervenes, as here, the parties are discharged as to the specific obligations rendered impossible of performance (by the city obligor).
For the reasons stated, therefore, the judgment of the Circuit Court of Rock Island County is reversed and the judgment entered therein purporting to set aside the right-of-way deed and ordering defendant to institute condemnation proceedings is vacated.
Reversed and judgment vacated.
STOUDER, P. J., and SCOTT, J., concur.