Obstructions, such as rocks or blocks, at any point inside a trench ________ provide adequate support for drainage piping.

The presence of obstructions, such as rocks or blocks, inside a trench can significantly hinder the proper support and function of drainage piping. For drainage systems to operate effectively, it is essential that the pipes are laid in a clear, unobstructed trench that allows for proper grading and alignment. When there are obstructions, the pipe may not be able to settle correctly, which can lead to issues such as improper drainage, blockages, or even damage to the piping system.

Adequate support is crucial to maintain the integrity of the drainage system and to ensure that any water flow is not impeded. Therefore, it is clear that obstructions in a trench cannot provide adequate support. Proper installation guidelines recommend that trenches be kept free of debris, rocks, and blocks to ensure that drainage systems function as designed.