What type of utilities do closed or solid symbols represent?

Closed or solid symbols typically represent proposed utilities on engineering plans. These symbols indicate intentions for future installations or modifications that are not yet in place but are planned to be. The distinction of using solid symbols is important because it clearly differentiates these proposed features from existing utilities, which may be represented by different styles or line types, such as dashed lines or other variations.

In plan reading, understanding the representation of utilities is crucial for project execution, as it allows for accurate planning and coordination of new construction or modifications around existing infrastructure. Recognizing a proposed utility allows engineers and planners to work effectively within the design and construction phases while anticipating future developments.