Alde, Ore and Butley Estuaries
|Unitary Authority||East Anglia|
|SAC EU Code||UK0030076|
|Status||Designated Special Area of Conservation (SAC)|
|* This is the approximate central point of the SAC. In the case of large, linear or composite sites, this may not represent the location where a feature occurs within the SAC.|
General site character
Tidal rivers, Estuaries, Mud flats, Sand flats, Lagoons (including saltwork basins) (70%)
Salt marshes, Salt pastures, Salt steppes (25%)
Shingle, Sea cliffs, Islets (5%)
Download the Standard Data Form for this site as submitted to Europe (PDF <100kb)
Note When undertaking an appropriate assessment of impacts at a site, all features of European importance (both primary and non-primary) need to be considered.
Annex I habitats that are a primary reason for selection of this site
This estuary, made up of three rivers, is the only bar-built estuary in the UK with a shingle bar. This bar has been extending rapidly along the coast since 1530, pushing the mouth of the estuary progressively south-westwards. The eastwards-running Alde River originally entered the sea at Aldeburgh, but now turns south along the inner side of the Orfordness shingle spit. It is relatively wide and shallow, with extensive intertidal mudflats on both sides of the channel in its upper reaches and saltmarsh accreting along its fringes. The Alde subsequently becomes the south-west flowing River Ore, which is narrower and deeper with stronger currents. The smaller Butley River, which has extensive areas of saltmarsh and a reedbed community bordering intertidal mudflats, flows into the Ore shortly after the latter divides around Havergate Island. The mouth of the River Ore is still moving south as the Orfordness shingle spit continues to grow through longshore drift from the north. There is a range of littoral sediment and rock biotopes (the latter on sea defences) that are of high diversity and species richness for estuaries in eastern England. Water quality is excellent throughout. The area is relatively natural, being largely undeveloped by man and with very limited industrial activity. The estuary contains large areas of shallow water over subtidal sediments, and extensive mudflats and saltmarshes exposed at low water. Its diverse and species-rich intertidal sand and mudflat biotopes grade naturally along many lengths of the shore into vegetated or dynamic shingle habitat, saltmarsh, grassland and reedbed.
Annex I habitats present as a qualifying feature, but not a primary reason for selection of this site
Annex II species that are a primary reason for selection of this site
- Not Applicable
Annex II species present as a qualifying feature, but not a primary reason for site selection
- Not Applicable
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