Vetiver grass can help stop further collapsing of a pond bank. Vetiver grass is a tropical grass originate in India and south east Asia. This grass has a very strong root system. And can grow in a wide range of climatic condition from minus 15 degree to 50 degree Celcius. Virtually It can be grown in every condition.
"Virtually can be grown in every condition..."
Sounds like a recipe for disaster to me. Recommend staying away from exotic/invasive species until ample research can be performed on it's potential effects.