Why this Catchment?

Over view

Why this Catchment?

The micro-catchment was selected in the GIS modelling step because it contains a large number of properties near Awliscombethat are

potentially at flood risk. The map below shows which buildings overlap with the EA’s modelled “Flood Zone 2” area, specifically areas at risk of flooding from rivers, as identified during the micro-catchment mapping process.

There are 9 buildings potentially at risk out of 71 in the catchment, approximately 12.7% of them. The catchment’s size of 9.58km2 gives an area of 1.06km2 per building at risk.

The water framework directive (WFD) status in the wider Wolf (Otter) waterbody catchment is Poor. If property owners are willing to work with land owners and vice versa, then small-scale NFM measures upstream in the catchment have the potential to benefit a large number of properties and improve water quality.

Micro-catchment Over view

Topography

The micro-catchment covers the rural area to the north west of Awliscombe and includes several small settlements, including Wolverstone. The A373 runs along the south of the catchment connecting it with Honiton to the East. The micro-catchment forms the watershed for the River Wolf that flows southwards through the catchment with several tributary’s feeding in from the east and west. Overall, the micro-catchment falls within the Awliscombe County Parish and is administered by Awliscombe Parish Council. The map on the right shows the steepness of slopes. A plateau with a steep ridge lines the catchment edges to the north, east, and west, while the majority of the catchment forms a bowl with fairly low, uniform slopes, particularly in the south and central areas. The River Wolf runs along the valley bottom.

Micro-catchment Over view

Land Cover

The way the land is used has significant impacts on flood management. Land use has been mapped here using the Centre for Ecology and Hydrology’s (CEH) Land Cover Map 2019. This is a model derived from satellite imagery at 25m resolution. The land use here is primarily improved grassland, accounting for 67% of the catchment, followed by woodland that covers another 22%. The wooded areas of the catchment are largely broadleaved woodland that follow the ridge line, with some small patches of coniferous woodland in the northwest on top of the plateau. There are also some scattered areas of land used for arable and horticulture.

It should be noted that this land cover map model is not a perfect representation of land use as it simplifies UK land cover into very broad classes.

Micro-catchment Over view

Land Cover

Land use observed during the catchment walkover mostly matched the land use mapped here using the Centre for Ecology and Hydrology’s (CEH) Land Cover Map 2019 above.

The catchment is mostly pasture and arable (maize at the time of survey) with trees around the upland watershed area as the map depicts.

The Western upper extent, in behind the trees on Wolverstone Moor, appeared to slightly differ from the mapped land use as it was proportionally weighted towards maize production rather than grassland.

The majority of the catchment appears to be supporting dairy herds for milk production.

It was generally observed that a lot of the arable location had a consistent slope, which, if left uninterrupted, lends itself to rapid run-off of surface water. Mid-catchment looking South East (downstream) across the valley towards Awliscombe