What is a difference between using bales and rock around an area drain?

Bales are typically constructed from straw or hay and are designed to slow down water flow, promoting sedimentation and allowing some water to percolate through the material. However, they inherently have a structure that limits water movement compared to rock barriers.

Rock, on the other hand, tends to create a more permeable barrier since it does not restrict water flow as much as bales do. As a result, water is likely to flow through the gaps between the rocks, which means that water is not held back in the same way as it would be with bales.

In this context, the statement that bales do not allow for percolation through the material is accurate, as they primarily function to impede flow and capture sediment rather than facilitate drainage. This characteristic is particularly relevant in erosion and sediment control strategies, where understanding the filtration ability of various materials is crucial for effective stormwater management.