(a)

(1) No local authority shall enact or enforce any rule or regulation in conflict with the provisions of this subtitle unless expressly authorized in this subtitle.

(2) Local authorities may, however, adopt additional traffic regulations which are not in conflict with the provisions of this subtitle.

(3) Local authorities may enact and enforce traffic rules and regulations which are not in conflict with the provisions of this subtitle for private roadways but only after being granted express permission by the owner of the private roadway within the planned community.

(b) The provisions of this subtitle shall not be deemed to prevent local authorities with respect to streets and highways under their jurisdiction and within the reasonable exercise of the police power from:

(1) Regulating the standing or parking of vehicles, including the ability to establish districts for the purpose of limiting the time, place, and manner of public parking in designated areas;

(2) Regulating traffic by means of police officers or traffic control signals;

(3) Regulating or prohibiting processions or assemblages on the highways;

(4) Designating particular highways as one-way highways and requiring that all vehicles thereon be moved in one specific direction;

(5) Regulating the speed of vehicles in public parks;

(6) Designating any highway as a through highway and requiring that all vehicles stop before entering or crossing it or designating any intersection as a stop intersection and requiring all vehicles to stop at one (1) or more entrances to the intersection;

(7) Restricting the use of highways as authorized in §§ 27-35-101 -- 27-35-111; and

(8) Regulating or prohibiting the traffic from and use of mopeds, three-wheeled vehicles, and other similar vehicles.

(c) No ordinance or regulation enacted under subdivision (b)(1), (4), (5), (6), or (7) of this section shall be effective until signs giving notice of local traffic regulations are posted upon or at the entrances to the highways or parts affected, as may be most appropriate.

(d) No provision of this subtitle, of other state traffic laws, or of any local traffic ordinance or regulation enacted under authority of subdivision (a)(3) of this section shall be effective on a private roadway of a planned community until signs giving notice of the owner's grant of permission to enforce those state and local traffic regulations are posted upon or at the entrances to the planned community's private roadways or affected parts thereof.