| Hazel Brook | |
| Name Other: | Hen |
| Map: | Trym and Hazel Brook, Bristol.jpg |
| Subdivision Type1: | Country |
| Subdivision Name1: | England |
| Subdivision Type4: | District |
| Subdivision Name4: | South Gloucestershire |
| Subdivision Type5: | Municipality |
| Subdivision Name5: | Bristol |
| Length: | 2miles |
| Source1: | Cribbs Causeway |
| Source1 Location: | South Gloucestershire, West of England, England |
| Source1 Coordinates: | 51.525°N -2.613°W |
| Source1 Elevation: | 263feet |
| Mouth: | Coombe Dingle |
| Mouth Location: | Bristol, West of England, England |
| Mouth Coordinates: | 51.495°N -2.641°W |
| Mouth Elevation: | 195feet |
| Custom Label: | River system |
| Custom Data: | Bristol Avon |
The Hazel Brook, also known as the Hen,[1] [2] is a tributary of the River Trym in Bristol, England. It rises at Cribbs Causeway in South Gloucestershire. From there, its course takes it south, passing the western end of Filton Aerodrome on its left bank, through Brentry and Henbury before dropping through a steep limestone gorge in the Blaise Castle estate. It continues south through two lakes before joining the Trym at Coombe Dingle.[3] [4]
Surface run-off in the upper catchment of the Hazel Brook, especially from the large retail centre at Cribbs Causeway, sends a good deal of silt into the system, slowing the flow and creating a risk of flooding downstream in the Trym. This problem has now been partially alleviated by the construction of the Catbrain attenuation reservoir near Cribbs Causeway.[5] Measurements of pollution by the city council show the water to be relatively clean.[6] [7]