En Banc. Durham, J. Dore, C.j., and Utter, Brachtenbach, Dolliver, Andersen, Smith, Guy, and Johnson, JJ., concur.
Appellants*fn1 challenge the constitutionality of a Yakima city ordinance contending that it either is preempted by, or is in direct conflict with, the state fireworks law, RCW 70.77. Upon cross motions for summary judgment, which were limited by stipulation to the legal question of constitutionality under Const. art. 11, § 11, the trial court upheld the ordinance, granted summary judgment in favor of Yakima, and dismissed Brown's claim. Brown appealed and this court granted his motion to transfer. We affirm.
Washington's state fireworks law is codified at RCW 70.77. RCW 70.77.395, with certain exceptions not relevant here, provides:
[N]o common fireworks shall be sold or discharged within this state except from twelve o'clock noon on the twenty-eighth of June to twelve o'clock noon on the sixth of July of each year. No common fireworks may be sold or discharged between the hours of eleven o'clock p.m. and nine o'clock a.m.
(Italics ours.) Yakima Ordinance 3169 (the ordinance), which became effective June 24, 1989, provides, in part:
No common fireworks shall be sold or offered for sale at retail within the City of Yakima except from twelve noon on the twenty-eighth day of June to eleven o'clock p.m. on the fourth day of July of each year . . . No common fireworks may be sold or discharged between the hours of eleven o'clock p.m. and nine o'clock a.m.
B. It is unlawful for a person to ignite, discharge, use or explode any common fireworks except between the hours of 9:00 a.m. and 11:00 p.m. on July 4th.
(Italics ours.) Thus, the ordinance is more restrictive than the statute as to the dates and times fireworks may be sold or used. Brown contends that the more restrictive language renders the ordinance unconstitutional.
 The ordinance is presumed constitutional and the "burden of showing otherwise rests heavily" on Brown. Louthan v. King Cy., 94 Wash. 2d 422, 428, 617 P.2d 977 (1980). Brown's sole challenge to the ordinance is brought under Const. art. 11, § 11, which provides:
Any county, city, town or township may make and enforce within its limits all such local police, sanitary and other regulations as are not in conflict with general laws.
Article 11, section 11 is a direct delegation of police power.
[This power is] as ample within its limits as that possessed by the legislature itself. It requires no legislative sanction for its exercise so long as the subject-matter is local, and the ...