How should depths that are above the survey datum be represented?

Depths that are above the survey datum should be represented in black, which is a standard practice in surveying to ensure clarity and consistency in the representation of data. Using a solid line in black helps differentiate these depths from other types of measurements or annotations on the survey. This method allows for easy recognition and interpretation by anyone reviewing the survey, facilitating effective communication of the information.

Adopting a uniform color scheme, such as black for above datum depths, supports the overall readability of survey documents and is crucial for avoiding confusion with other elements that may be represented through alternative colors or styles. Therefore, it's vital for surveyors to adhere to these standard practices to maintain clarity and professionalism in their work.