This report deals with internal erosion. In France, every year, one hydraulic earthen structure (small dam, canal or flood embankment) is breached by internal erosion. The mitigation of the risk of internal erosion was the purpose of a national research program called Erinoh. The risk assessment of internal erosion made by Erinoh is reported in three steps: 1. laboratory tests: main mechanisms of internal erosion are evaluated in lab tests on intact or compacted samples, 2. methods of detection on site : the flaws or defects on site (leaks, cavities, other anomalies) are localized and sometimes monitored by accurate methods of detection, 3. engineering methods : the risk assessment is finally driven by functional analysis, behaviour assessment and engineering rules based on filter criteria and erosion thresholds. Every step is described in a handbook. This report presents some outputs of the Erinoh Project and invites the practitioners to read the 3 handbooks for applications.