The formation of a 200ha (494.211 acre) freshwater lake through the creation of the Cardiff Bay Barrage (completed in 2001, NPRN 305755), was a key aspect of the rejuvenation of Cardiff Bay. However, concerns that the transformation of the tidal muddy salt-water flats and marshland into a freshwater lake endangered local species within as Site of Special Scientific Interest. A site along the north shore of Cardiff Bay between the St David's Hotel and the River Taff was therefore transformed into an approximately 8ha (19.768 acre) wildlife reserve. Opened on 25 July 2002 with engineering work by Edmund Nuttall (Wales) Ltd largely completed by November 2003, the reserve includes marshland and lagoons separated from the freshwater lake by a bund. There are also a boardwalk and viewing platform for the benefit of visitors.

(Sources: Hilling, `Through Tiger Bay to Cardiff Bay?, Transactions of the Honourable Society of Cymmrodorion (1990), 189; Ellis, `Wet `n? Wild?, Landscape: The Journal of the Landscape Institute (Nov 2004))
A.N. Coward, RCAHMW, 06.08.2018