Estuary detail

Below is an interactive map and a table of parameters derived through various sources – Nature Conservancy Council (Davidson et al, 1991), EMPHASYS (2000c), Dyer (2002) in Futurecoast, Townend (2005), ABPmer (2024) and ABPmer (2025). The data is indicative of recently determined bulk properties suitable for broadscale intercomparison of estuaries.

Alternatively take a look in the viewer.

Estuaries Database Viewer View in Estuaries Database Viewer
Estuary ID 61 
JNCC ID 143 
Name of estuary Otter Estuary 
Alternative name  
Grid reference SY075825  
WFD water body ID GB510804505500 
WFD water body name Otter 
MAGIC URL link MAGIC link 1 
Latitude 50.63402649 
Longitude -3.30881654 
JNCC classification Bar Built Estuary  
Updated classification Spit Enclosed   read more on estuary classification..
Tidal classification Macrotidal  
Spring tidal range (m) 3.6  
Mean High Water Springs (mODN) 2.17 
Mean Low Water Springs (mODN) -1.43 
Mean Tide Level (mODN) 0.3 
Mean river flow (m3/s) 5.4 
Low river flow (m3/s)  
High river flow (m3/s)  
Name of furthest downstream flow gauge Dotton  
DEFRA Hydrology Gauge Data Explorer URL link DEFRA Hydrology Gauge link    
Area of basin (Ha) 35.6  
Intertidal area (Ha) 19  
Shoreline length (km) 6.1  
Channel length (km) 1.1  
Mouth width (m) 10  
Valley width (m) 450  
Volume at mean tide level (m3) 0  
Surface area at mean tide level (m2) 0  
CSA at mean tide level (m2) 40  
Volume at low water (m3) 0  
Surface area at low water (m2) 0  
CSA at low water (m2) 0 
Volume at high water (m3) 67100 
Surface area at high water (m2) 67600 
CSA at high water (m2) 178 
Volume of tidal prism (m3) 67100 
Dronkers' gamma (nondim)  
Storage volume over intertidal (m3) 67100 
Channel volume to MTL (m3) 0 
Ratio of storage volume to channel volume (nondim)  
Hydraulic depth at MTL (m)  
DEFRA Catchment Data Explorer URL link DEFRA Catchment link   
Estuary template download link  

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Last Modified on: 20 June 2025
Printed from the Estuary Guide on 01/11/2026 02:32:14