River Exe

• Where is the river exe

  South west of England in Devon
• What is the size of the catchment area?

  601 km2
• Where is the river's source located?

  Exmoor, an upland area of moorland and peat bogs rising to 514 m above sea level
• What is the predominant land use in the catchment?

  Grassland, accounting for 67% of the land use
• What type of rock underlies the majority of the catchment?

  Impermeable sandstones
• What is the average annual rainfall in the catchment area of the River Exe in the UK?

  1295 mm
• Why does much of the rainfall in the catchment area of the River Exe form runoff instead of infiltrating?

  Impermeable nature of underlying rocks, saturated upland peat, and drainage ditches
• What is one reason for the relatively slow response of the River Exe to rainfall events?

  82% of the catchment is woodland or grassland
• What is the history of flooding on the River Exe?

  The River Exe has experienced significant flooding in the past, with major floods occurring in 1960.
• What is the future projection for flooding on the River Exe?

  The River Exe is projected to experience more flooding in the future due to climate change making extreme weather events more likely.
• What percentage of houses in the Exe catchment are at risk of a 1 in 100 year flood?

  10% of the houses in the Exe catchment are at risk of a 1 in 100 year flood, which is relatively high.
• Why is blocking drainage ditches on Exmoor considered a strategy for flood prevention on the River Exe?

  Blocking drainage ditches on Exmoor helps attenuate more water in the upper catchment, preventing it from entering the river channel and causing flooding.
• What is the impact of draining peatlands on the River Exe?

  Draining peatlands dries out the peat, increases flood risk downstream, causes erosion of dried peat, and releases carbon into the water.
• How does draining peatlands affect water quality in rivers?

  Draining peatlands leads to the dissolution of organic carbon in water, making it brown and requiring water companies to remove the color.
• What is the solution to the problems caused by draining peatlands on Exmoor?

  The solution involves blocking drainage ditches, restoring the peat to its saturated state, and convincing landowners of the benefits despite potential agricultural losses.
• What is the Exmoor Mires Project focused on?

  The Exmoor Mires Project has researched the effects of blocking drainage ditches on Exmoor between 2000 and 2015.
• What are the benefits of peat restoration on Exmoor?

  Restoration of peat bogs on Exmoor has resulted in reduced water runoff during heavy rainfall, increased water storage in the peat, and potential flood prevention downstream.
• What was the 2015 target for the Exmoor Mires Project?

  The 2015 target for the Exmoor Mires Project was to restore 2000 hectares of moorland.
• What is the impact of blocking drainage ditches on Exmoor?

  Blocking drainage ditches on Exmoor allows the moorland to hold more water, release it slowly, and reduce flooding downstream.
• What is the observed rise in water table levels attributed to on Exmoor?

  The rise in water table levels on Exmoor, up to 2.65cm, is attributed to ditch blocking and moorland restoration.
• What is the potential environmental benefit of peat restoration on Exmoor?

  Peat restoration on Exmoor could provide a significant buffer against downstream flooding in rivers like the Exe by enhancing water storage.
• What is the name of the dam that controls the river regime

  Wimbleball