delivered the opinion of the court:
Plaintiff Chicago Park District (Park District) filed this action against defendant city of Chicago (the city), seeking a declaratory judgment that the Chicago boat-mooring tax was unconstitutional. On the Park District’s motion for a temporary restraining order and preliminary injunction to prevent the city from collecting the tax, the trial court ruled that the Park District did not have standing to sue, and did not demonstrate irreparable harm or a likelihood of success on .the merits. Following the denial of its motion, the Park District brings this interlocutory appeal.
In December 1983, the Chicago city council enacted chapter 200.8, the Chicago boat-mooring tax, requiring all persons who moor or dock watercraft in any body of water within the city’s corporate limits to pay a tax to the city. The tax, at a rate of 50% of the mooring or docking fee, is due on March 1 of each year for permits issued that year. The Park District controls eight harbor facilities providing moorings for approximately 7,200 boats. Each person issued a mooring permit by the Park District must pay the boat-mooring tax directly to the city. Additional moorings within the city limits, not controlled by the Park District, are also covered by the boat-mooring tax.
Following the adoption of the tax, the Park District filed suit alleging that the city’s ordinance is an unconstitutional interference with its grant of authority from the State to provide recreational harbors at a reasonable fee. At a hearing on February 17, 1984, the trial court denied the Park District’s motion for a temporary restraining order. On February 24, 1984, the court dénied the Park District’s motion for a preliminary injunction.
On appeal, the Park District contends that the trial court erred in denying its motion for a preliminary injunction because the State statutory scheme regulating recreational harbors preempts the city from enacting its own legislation under its home rule authority and the State legislation removes recreational harbors from the government and affairs of the city. The Park District also argues that it has standing to sue, and that the tax is in effect a regulatory measure which impermissibly burdens the Park District.
Initially, the city maintains that the appeal is moot because the trial court, on its own motion, has enjoined the city from collecting the mooring tax. We find, however, that since the preliminary injunction may be dissolved at any time before a final determination on the merits of the Park District’s cause of action, the appeal of the denial of the preliminary injunction is not moot.
We next address the trial court’s finding that the Park District did not have standing to sue. Section 2 — 701 of the Illinois Code of Civil Procedure allows the court to make a binding declaration of a party’s rights where an actual controversy exists. (Ill. Rev. Stat. 1983, ch. 110, par. 2—701; Exchange National Bank v. County of Cook (1955), 6 Ill. 2d 419, 129 N.E.2d 1.) A plaintiff has standing where he has a real interest in the subject matter of the controversy. (City of West Chicago v. County of Du Page (1979), 67 Ill. App. 3d 924, 385 N.E.2d 826.) The plaintiff must allege a direct injury to his rights and not merely that he will suffer in some indefinite way. Dolnick v. Redmond (1972), 4 Ill. App. 3d 1037, 283 N.E.2d 113.
In its complaint, the Park District alleges it has plenary authority over recreational harbors; that it has issued revenue bonds pursuant to its authority; that the boat-mooring tax interferes with its bond contracts and regulatory functions; and that the tax will cause an irreplaceable loss of boaters affecting its revenues. These allegations demonstrate a real interest in the subject matter of the controversy. Although the Park District is not required to pay or collect the tax, the impact of the tax on mooring benefit holders directly injures the District and its revenue planning. The Park District has standing to challenge the tax.
The trial court also found that the Park District had not shown an irreparable injury or the probability of success on the merits to warrant a preliminary injunction.
A preliminary injunction may be granted where the plaintiff demonstrates that there is no adequate remedy at law and that he will be irreparably harmed if the injunction is not granted; that the threatened harm to him is immediate, certain and great while the inconvenience to the opposing party is small; that he has a reasonable likelihood of success on the merits; and that granting the preliminary injunction will not have an injurious effect on the general public. (McCormick v. Empire Accounts Service, Inc. (1977), 49 Ill. App. 3d 415, 364 N.E.2d 420; Professional Business Management, Inc. v. Clark (1967), 83 Ill. App. 2d 236, 227 N.E.2d 371.) Our review is limited to whether the trial court abused its discretion in denying the requested injunction. Lonergan v. Crucible Steel Co. of America (1967), 37 Ill. 2d 599, 229 N.E.2d 536; Stocker Hinge Manufacturing Co. v. Darnel Industries, Inc. (1978), 61 Ill. App. 3d 636, 377 N.E.2d 1125.
In view of our belief that the Park District has not shown probable success on the issue of the constitutionality of the boat-mooring tax, we deem it unnecessary to consider the Park District’s claim that it has demonstrated irreparable harm.
While recognizing the city’s home rule power to tax, the Park District maintains that State law preempts the field of recreational harbors preventing the city from imposing its mooring tax. The Park District argues that the legislature has expressed an exclusive State interest' in recreational harbors through comprehensive legislation and that such action by the State removes recreational harbors from the government and affairs of the city.
Article VII, section 6(a), of the Illinois Constitution grants to home rule units the power to tax in those areas pertaining to its government and affairs. (Ill. Const. 1970, art. VII, sec. 6(a).) The taxing power is to be construed liberally (Ill. Const. 1970, art. VII, sec. 6(m); Mulligan v. Dunne (1975), 61 Ill. 2d 544, 338 N.E.2d 6), but is not without limitation. The General Assembly may deny or limit a home rule unit’s power to tax by a three-fifths vote of its members. Ill. Const. 1970, art. VII, sec. 6(g); Mulligan v. Dunne (1975), 61 Ill. 2d 544, 338 N.E.2d 6; compare Hutchcraft Van Service, Inc. v. City of Urbana Human Relations Com. (1982), 104 Ill. App. 3d 817, 433 N.E.2d 329.
The Park District, relying on its grant of authority to build, finance and regulate harbors, urges that the city is specifically precluded from any governmental participation in recreational harbors. A similar argument was presented to our supreme court in Mulligan v. Dunne (1975), 61 Ill. 2d 544, 338 N.E.2d 6, and Town of Cicero v. Fox Valley Trotting Club, Inc. (1976), 65 Ill. 2d 10, 357 N.E.2d 1118. In Mulligan, plaintiffs contested the Cook County liquor tax, arguing that the State had preempted the area by its extensive regulation of the liquor industry. Similarly, plaintiffs in Town of Cicero argued that extensive regulation by the State in the field of horse racing precluded the municipality from imposing an amusement tax on horse racing events. In both cases the supreme court recognized a distinction between the power to regulate and the power to tax and held that extensive regulation did not preempt the power to tax. (See Greater Chicago Indoor Tennis Clubs, Inc. v. Village of Willowbrook (1976), 63 Ill. 2d 400, 349 N.E.2d 3.) Likewise, we hold in the present case that extensive regulation did not preclude the city from imposing a tax.
We also reject the Park District’s contention that recreational harbors are not within the government and affairs of the city. The Park District refers us to only one case in which a home rule unit tax was struck down. In Ampersand, Inc. v. Finley (1975), 61 Ill. 2d 537, 338 N.E.2d 15, the court invalidated a Cook County law library tax assessed against all parties in civil court actions. Central to that decision was the pervasive State interest in the courts mandated by the constitution. In construing Ampersand in a later case, the court said, “Ampersand merely reflects a longstanding principle that governmental bodies must operate subject to constitutional restraints ***.” Town of Cicero v. Fox Valley Trotting Club, Inc. (1976), 65 Ill. 2d 10, 20, 338 N.E.2d 15; see Board of Education v. City of Peoria (1979), 76 Ill. 2d 469, 394 N.E.2d 399 (home rule unit may not impose tax on school district where State has constitutional power over schools).
The Park District also points to two statutes in its attempt to establish a pervasive State interest which removes recreational harbors from the government and affairs of the city. Section 26 of “An Act in relation to the regulation of the rivers, lakes and streams of the State of Illinois” provides that nothing in the Act shall be construed to impair the rights of Illinois citizens to enjoy such bodies of water. (Ill. Rev. Stat. 1983, ch. 19, par. 73.) Section 26.3(g) of “An Act in relation to *** the Chicago Park District” authorizes the Park District to establish and collect fees for all harbor facilities. (Ill. Rev. Stat. 1983, ch. 105, par. 333.23n(g).) However, neither of these provisions reflect a statewide constitutional interest in recreational harbors, such that the city may not impose its home rule power to tax.
We find no merit in the Park District’s argument that the mooring tax is not a tax but a usurpation of its authority to set fees for recreational harbors. The mooring tax in no way regulates access to recreational harbors, but appears to be strictly a revenue measure. While every tax on an activity increases the ultimate cost of that activity to the consumer, this factor does not change the tax from a revenue measure to a regulatory measure.
Relying on Board of Education v. City of Peoria (1979), 76 Ill. 2d 469, 394 N.E.2d 399, the Park District urges us to find that the 50% mooring tax imposes an unreasonable burden upon it. According to the Park District, the supreme court upheld Peoria’s 2% liquor and food sales tax because it was incidental, while this court should find the mooring tax invalid because a 50% tax is not incidental. From our reading of the City of Peoria case, the court was referring to the burden of collecting the tax, not to the amount of the tax. In the case before us, the city has not imposed any burden on the Park District to collect its mooring tax.
We hold that the trial court did not abuse its discretion in denying the Park District’s motion for a preliminary .injunction since the Park District did not demonstrate a reasonable likelihood of success on the merits.
Accordingly, the judgment of the circuit court of Cook County is affirmed.
Judgment affirmed.
WHITE, J., concurs.