No person shall ride or operate any bicycle on top of the concrete cap on the flood wall in the Payran Street area adjacent to the Petaluma River, specifically from four hundred feet downstream of the Lakeville Street Bridge to six hundred feet upstream of the Payran Street Bridge; and adjacent to Washington Creek from the confluence of the Petaluma River and Washington Creek to the Holly Lane Bridge over Washington Creek. (Ord. 2121 NCS § 3, 2001.)