What must be ensured about the materials used in earthen embankment construction?

When constructing earthen embankments, it is crucial that the materials used are free of roots, stumps, and debris. This is vital for several reasons.

Firstly, organic materials such as roots and stumps can decompose over time, leading to settlement and potential failure of the embankment. The stability of the embankment relies on a solid and consistent structure; any decay or movement caused by organic matter can create voids or weak spots that compromise its integrity.

Secondly, debris can include various sizes of materials that may not bond well with the primary soil components. This can create inconsistencies in density and strength, which are essential for an embankment that needs to withstand hydraulic pressures and other loads.

Ensuring that materials are clean and free from any organic and extraneous matter significantly contributes to the overall stability, durability, and performance of the earthen embankment, making this requirement a fundamental aspect of sound engineering practices in stormwater management and civil construction.