English to German Law/Patents Agriculture

Aus einem landwirtschaftlichen Pachtvertrag:

At Lessee's expense, the Lessee agrees to perform and carry out the following covenants:
- To inspect all tile lines and to keep ditches, tile drains, tile outlets, and ***grass waterways*** open and in good repair;

The Lessee further agrees, unless the Lessee shall first have obtained the written consent of the Lessor, as follows:
- Not to plow or otherwise break up any permanent pasture, drainageways, ***grassed waterways***, or ditches, nor to undertake any operation that will injure the Premises;

Wenn ich den Begriff bei Google eingebe, erhalte ich wunderschöne Bilder, allerdings habe ich keine Ahnung, wie man das im Deutschen nennt.
Zugewachsene oder begrünte Wasserwege???

Vielen Dank!