The answer to 'drainage system overgrown' is that a drainage system that is overgrown with vegetation can become clogged and ineffective. This can lead to standing water, flooding, and other issues around your property. Common causes include lack of maintenance, heavy rainfall, and encroaching plant growth.
Some symptoms of an overgrown drainage system include water pooling in low areas, soggy soil, and visible debris or plant growth in the drainage pipes or channels. To address this, you'll need to clear out any vegetation, leaves, or other debris blocking the flow of water. This may require manual removal, using a hose or pressure washer, or even replacing damaged drainage components.