A rubble pit is a trench filled with blue metal gravel and topped with sand to help disperse and remove roofwater. It serves as a simple, effective method for managing stormwater runoff, particularly from roofs.
Based on the provided reference, here's a breakdown of its components and function:
- Structure: It begins as a dug trench.
- Filling: This trench is primarily filled with blue metal gravel.
- Topping: A layer of sand is placed on top of the gravel.
- Purpose: The main goal is to disperse and remove roofwater, which is typically collected via downpipes connected to stormwater pipes.
- Connection: These stormwater pipes connect to the pit.
- Dispersal Mechanism: Within the pit, there is a section of slotted pipe. This slotted section allows the collected water to evenly disperse through the gravel.
- Function: The gravel and sand layers facilitate the absorption and gradual dispersal of water into the surrounding soil, preventing surface flooding and potential damage.
In essence, a rubble pit acts as a basic soakage trench designed to handle stormwater runoff locally, utilizing layered materials to filter and distribute the water underground.
