A "lateral water hazard" is a water hazard or that part of a water hazard so situated that it is not possible, or is deemed by the Committee to be impracticable, to drop a ball behind the water hazard in accordance with Rule 26-1b. All ground and water within the margin of a lateral water hazard are part of the lateral water hazard.

When the margin of a lateral water hazard is defined by stakes, the stakes are inside the lateral water hazard, and the margin of the hazard is defined by the nearest outside points of the stakes at ground level. When both stakes and lines are used to indicate a lateral water hazard, the stakes identify the hazard and the lines define the hazard margin. When the margin of a lateral water hazard is defined by a line on the ground, the line itself is in the lateral water hazard. The margin of a lateral water hazard extends vertically upwards and downwards.

A ball is in a lateral water hazard when it lies in or any part of it touches the lateral water hazard.

Stakes used to define the margin of or identify a lateral water hazard are obstructions.

Note 1: That part of a water hazard to be played as a lateral water hazard must be distinctively marked. Stakes or lines used to define the margin of or identify a lateral water hazard must be red.

Note 2: The Committee may make a Local Rule prohibiting play from an environmentally-sensitive area defined as a lateral water hazard.

Note 3: The Committee may define a lateral water hazard as a water hazard.