Final answer:
Rocks or blocks can support drainage piping inside a trench.
Step-by-step explanation:
True, rocks or blocks at any point could support drainage piping inside a trench. They can be used to create a stable base for the piping and prevent it from sinking into the ground. The rocks or blocks provide support and help to facilitate drainage by allowing water to flow freely through the gaps between them.
The bottom line is this: long runs of pipe need to be supported to take the weight off threaded, soldered, or cemented connections. The good news is that you can do this easily with pipe hangers, wood scraps, or even wire hangers. In addition, there are a ton of different hanger types for every kind of situation.
Flexible plastic pipe and rigid polyethylene (fuseal or similar approved drainage system) shall have continuous supports for the entire length. ABS and PVC plastic pipe shall be supported at maximum 5- foot intervals.