Потребен ми е поширок контекст, но од приложената реченица најверојатно се работи за gully.

Еве неколку дефиниции:

1. deep ditch cut by running water (especially after a prolonged downpour)
2. a small valley or ravine originally worn away by running water and serving as a drainageway after prolonged heavy rains.
3. a channel or small valley, esp one cut by heavy rainwater
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