Fen Management Handbook - Scottish Natural Heritage

Case Study 5.2
Fen Management and Restoration
– Redgrave and Lopham Fens
At 125 ha, Redgrave and Lopham Fens is one of the largest valley fens in England,
forming the headwaters of the River Waveney and the Little Ouse River on the
Norfolk-Suffolk border (grid reference TM050797). Noted for its rare wetland
habitats since the beginning of the 20th century, it is a designated SSSI and
National Nature Reserve part of the Waveney and Little Ouse Valley SAC, a Ramsar
wetland, and a Suffolk Wildlife Trust nature reserve. The site supports several
different types of fen including purple moor-grass meadows, saw-sedge beds,
bluntflowered rush stands as well as wet heath communities. There is also an
extremely rich invertebrate fauna including one of only three British populations of
the fen raft spider Dolomedes plantarius, a Red Data Book Category 1 species.
Before the 1950s, the fen was fed by groundwater rising by artesian pressure
through or past layers of sand, gravel, clay, peat and silt. Seepages and
groundwater flushes were found across the site but were concentrated along the
margins. The complex geology, and the variable chemistry of the soils and peat
produced nutrient-poor waters of varying pH and base-content. The vegetation
reflected the variation in water chemistry.
The historic management of the fen declined and was abandoned between
1940 and 1960. From the mid 1950s to the mid 1960s the River Waveney
was deepened in association with more efficient drainage in other parts of the
catchment. In the 1960s, a public supply borehole was brought into use next
to the fens. This changed the water regime from one of a variety of sources to a
dependence on winter storage of rain and floodwater. The lowered water levels and
lack of traditional grazing and cutting was followed by scrub invasion and loss of the
previous plant communities. The change was exacerbated by nutrient release from
the drying and oxidising fen peat.
Management rationale
In the 1990s the Essex and Suffolk Water Company, managers of the borehole
at Redgrave, commissioned a series of reports confirming that the borehole was
removing the essential groundwater inputs to the fen. The deepening of the River
Waveney was identified as another principal cause of change.
The Restoration Project Partnership
A restoration project steering group was established, and rehabilitation
targets drawn up. The overall cost of restoration was estimated at
£3.6m. The Heritage Lottery Fund provided funding for visitor facilities
and land acquisition, and an ESA (now HLS) agreement was developed
with the inclusion of a new Fen Tier area payment.
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